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Dietary options for the sauropod dinosaurs from an integrated botanical and paleobotanical perspective


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during the majority of the Mesozoic, from the Tri-assic to the mid Cretaceous, the food plants of the sauro-pod dinosaurs were virtually limited to ferns, fern allies, and gymnosperms because the diversification of the an-giosperms, which include the broad-leaved trees and grasses of today, only began in the Late Cretaceous. In this chapter, the preferences of the sauropods for one or more of these Mesozoic plant groups are evaluated by means of a survey approach that integrates botanical and paleobotanical data. These data include the growth hab-its of the nearest living relatives of these plant groups, their habitat, the amount of biomass produced, and the ability to regrow shoots, branches, and leaves after injury through herbivory. The relative quantities of energy and essential nutrients yielded to herbivores with hindgut fermentation, the consumption of the various plant groups by modern herbivores, and the coeval occurrence of sauropods and individual plant groups in the fossil record are other major factors taken into consideration here. As a result of this extensive survey, it appears that Araucaria, Equisetum, the Cheirolepidiaceae (an extinct conifer family), and Ginkgo would have been most acces-sible, sustaining, and/or preferred sources of food for the sauropods. Moderately accessible, sustaining, and/or commonly encountered plants would have been other conifers such as the Podocarpaceae, Cupressaceae, and Pinaceae. Less commonly browsed by the sauropods, es-pecially by large, fully grown individuals, would have been forest-dwelling ferns such as Angiopteris and Os-munda. The least frequently eaten plants were probably the cycads and bennettitaleans.
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Dietary Options for the Sauropod Dinosaurs from an
Integrated Botanical and Paleobotanical Perspective
during the majority of the Mesozoic, from the Tri-
assic to the mid Cretaceous, the food plants of the sauro-
pod dinosaurs were virtually limited to ferns, fern allies,
and gymnosperms because the diversification of the an-
giosperms, which include the broad-leaved trees and
grasses of today, only began in the Late Cretaceous. In
this chapter, the preferences of the sauropods for one or
more of these Mesozoic plant groups are evaluated by
means of a survey approach that integrates botanical and
paleobotanical data. These data include the growth hab-
its of the nearest living relatives of these plant groups,
their habitat, the amount of biomass produced, and the
ability to regrow shoots, branches, and leaves after injury
through herbivory. The relative quantities of energy and
essential nutrients yielded to herbivores with hindgut
fermentation, the consumption of the various plant
groups by modern herbivores, and the coeval occurrence
of sauropods and individual plant groups in the fossil
record are other major factors taken into consideration
here. As a result of this extensive survey, it appears that
Araucaria, Equisetum, the Cheirolepidiaceae (an extinct
conifer family), and Ginkgo would have been most acces-
sible, sustaining, and/or preferred sources of food for the
sauropods. Moderately accessible, sustaining, and/or
commonly encountered plants would have been other
conifers such as the Podocarpaceae, Cupressaceae, and
Pinaceae. Less commonly browsed by the sauropods, es-
pecially by large, fully grown individuals, would have
been forest-dwelling ferns such as Angiopteris and Os-
munda. The least frequently eaten plants were probably
the cycads and bennettitaleans.
Botanically, it seems that the thick-cuticle conifers, toxic
cycads, and low-biomass ferns would have offered little in
terms of palatable, sustaining fodder to the early and mid
Mesozoic sauropods, yet we know that giant sauropods did
exist and must have thrived on these plant groups. Indeed,
ferns and gymnosperms dominated the flora during the better
part of the Mesozoic, specifically, some 140 million years al-
together. The great diversification of the flowering plants, and
hence the onset of the modern flora, took place in the mid
Cretaceous, after about four fifths of the Mesozoic had already
passed by. Angiosperms, the producers of broad leaves, flowers,
and fruits in the present-day world, thus fed the herbivorous
dinosaurs for only a relatively short span of time.
The plant groups that greened the Earth from the Early Trias-
sic (251 million years ago) to the mid Cretaceous (100 million
years ago) included ferns and fern allies, cycads and bennet-
titaleans, seed ferns, ginkgophytes, and conifers. Like the dino-
saurs, some of these taxa—major groups such as the bennet-
titaleans, seed ferns, and the cheirolepidiaceans— went extinct
at the end of the Mesozoic, but others have survived to this day.
Dietary Options for the Sauropod Dinosaurs 35
Indeed, a few plants that have remained unchanged at the
genus level since the Mesozoic, for example, the horsetail Equi-
setum, the tropical ferns Angiopteris and Marattia, the maiden-
hair tree Ginkgo, and the southern conifer Araucaria. The living
species of these genera can be looked on as the embodiment of
close relatives that nourished the dinosaurs.
Although it is clear that herbivorous dinosaurs must have
fed on and attained gigantic sizes using nonangiospermous
plants, it is less obvious which of these plants—if any—they
might have preferred as a food source. Were some plant
groups more nutritious than others? Did the dinosaurs prefer-
entially live (and feed) in certain kinds of vegetation? Further-
more, after a herd of dinosaurs or perhaps just a particularly
hungry individual had decimated an area of its flora, were
some plants better able to recover and regenerate their foliage
than others, thus surviving another season to grow, repro-
duce, and possibly withstand another onslaught of herbivory?
This chapter tackles the question of dietary options for the
herbivorous dinosaurs, focusing on sauropods, by conducting
a survey of the preangiospermous Mesozoic flora, especially
in light of any nearest living relatives, to see how suitably
they would have served as dinosaur fodder in regard to their
growth habit, the habitat in which they grew, the amount of
biomass they were able to produce, their ability to regrow
shoots, branches, and leaves, and the quantity of energy and
important nutrients they would have offered herbivores. Al-
though these nonangiospermous plant groups are not usually
considered forage plants for modern plant eaters, reports
of consumption involving living animals are noted here
as well.
In addition to analyzing living plants, the fossil record can
be gleaned for clues to the food preferences of the sauropod
dinosaurs. For example, the coeval occurrence of both sauro-
pods and specific plant groups at the same fossil localities in-
creases the possibility that these dinosaurs fed on these plants,
assuming that these death assemblages represent the living
biota to a reasonable extent.
Finally, on the basis of data from living plants, extant her-
bivores, and the fossil record, each Mesozoic plant group is
rated comparatively for its likelihood as a food option for the
sauropod dinosaurs.
A number of approaches have been developed to try to find
out what sorts of plants herbivorous dinosaurs preferred feed-
ing on. These include using trace fossils, dinosaur morphol-
ogy, and plant factors such as morphology and physiology.
Trace Fossils
The most direct approach would seem to be the study
of plant remains in dinosaur coprolites or digestive-tract re-
mains. Yet this approach is not as straightforward as generally
assumed for several reasons, which were recently discussed in
great detail (Sander et al. 2010). In regard to coprolites, it is
difficult to positively and unequivocally trace fossilized fecal
material to a particular genus or even type of plant-eating
dinosaur. Even in the case of the putative sauropod coprolites
found in the same horizon as titanosaurs in the Upper Creta-
ceous Lameta Formation of India, there is some doubt that
such gigantic animals would have produced such small co-
prolites (Sander et al. 2010). Furthermore, it is questionable
whether the ‘‘soft’’ plant tissues, especially of fern fronds, re-
ported from these nodule-shaped structures (Mohabey 2005)
would have survived the three to four days of chemical and
mechanical processing in a large herbivore’s digestive system
(cf. Hummel & Clauss, this volume).
In the case of stomach remains and other reports of digestive-
tract remains, even if fossilized plant material is found inside a
dinosaur’s body cavity, it is still unclear whether this material
truly represents the digestive remains or a postmortem ac-
cumulation. In one well studied case of a mummified hadro-
saur, the highly diverse pollen flora in the plant material, cou-
pled with the uniform particle size of the plant megafossils,
plus the occurrence of an unusual mixture of charcoal, dino-
cysts, and other algae, led researchers to suggest that these
plant remains were washed into the body after death (Currie
et al. 1995).
Indeed, in a critical look at coprolite and digestive-tract re-
mains in herbivorous dinosaurs, Sander et al. (2010a) reported
that most cases are problematic in their authenticity, with the
exception of one well documented specimen of an apparently
frugivorous bird, Jeholornis prima from the Lower Cretaceous
of China (Zhou & Zhang 2002), with seeds in its gut, and of
another case consisting of clusters of pellet-like coprolites
with bennettitalean leaf cuticle from an English dinosaur (Hill
1976). It should be noted that in both of these instances, the
plant remains were monotypic in regard to plant parts (i.e.,
seeds or leaves) and generally monospecific in regard to plant
taxon (i.e., Carpolithes or bennettitaleans). This would be in
line with a feeding behavior in which the animal feeds on only
one type of plant part of a single species, depending on what is
ripe or available at the time. Thus, such cases would depict the
last meal eaten by the dinosaur immediately before death and
burial, and would be less likely to represent the spectrum of
the animal’s overall diet.
Dinosaur Morphology
Other approaches to deciphering herbivorous dinosaur
feeding habits involve the analysis of teeth, jaw mechanics,
skull shape, neck length, and other food-processing structures
such as gastric mills. Because this topic has also been subject to
a recent critical discussion (e.g., Sander et al. 2010a; Hummel
& Clauss, this volume), it will be not repeated here. However,
it should be noted that it is thought that the success of
the sauropod dinosaurs in regard to gigantism was based
in part on the fact that they did not chew, which enabled
them to ingest large mouthfuls of food rapidly and continu-
ously (Sander & Clauss 2008; Sander et al. 2010b; Hummel &
Clauss, this volume). Other probable factors included egg lay-
ing, a high growth rate, avian-style respiration, an ontoge-
netically flexible metabolic rate, and a long neck (Sander &
Clauss 2008; Sander et al. 2010a, 2010b; Griebeler & Werner,
this volume; Sander et al., this volume).
Plant Factors
The giant body size of sauropods, along with their need
to consume huge amounts of plant material for growth and
maintenance, necessarily means that they were bulk feeders.
As revealed by the cropping efficiency experiments on conifer
and angiosperm twigs carried out by Hummel & Clauss (this
volume, and references therein), sauropods would have been
most efficient when foraging on conifers, and not on angio-
sperms (i.e., broad-leaved trees) or ferns because they would
have received more biomass with each bite of conifer foliage.
Qualitatively, there are also differences in energy and nu-
trient yield between different plant groups. Although it had
been assumed for many years that the preangiosperm Meso-
zoic plants could have provided only low-quality fodder for
herbivorous dinosaurs (Coe et al. 1987; Taggart & Cross 1997;
Tiffney 1997; Midgley et al. 2002), recent empirical laboratory
experiments estimating the amount of energy yielded by the
nearest living relatives of the Mesozoic flora (Hummel et al.
2008; Sander et al. 2010a; Hummel & Clauss, this volume)
have shown that a number of ferns, conifers, and other gym-
nosperms actually offer herbivores relatively large amounts of
energy, comparable to or even surpassing grasses or broad-
leaved trees (see Hummel & Clauss, this volume). These high-
energy plants include horsetails such as Equisetum, ferns such
as Osmunda and Angiopteris, conifers such as Araucaria, Tor-
reya, Taxus, and Cephalotaxus, and the maidenhair tree Ginkgo.
Conversely, there are other plants, namely the cycads and
podocarps, that prove to be poor sources of energy. These new
perspectives reveal another factor that can be used in the eval-
uation of the various Mesozoic plant groups for their potential
as sauropod fodder and are incorporated here into the botani-
cal and paleobotanical data on each plant group.
Parameters Considered
To control for floral and faunal differences dependent on geo-
logical time, this chapter focuses on the Late Jurassic sites or
regions that have produced well documented sauropod fau-
nas and Mesozoic floras. Specifically, this encompasses the
Morrison Formation of the Western Interior of North Amer-
ica, the Patagonian region of southern South America, and the
Tendaguru Beds in Tanzania, East Africa (Fig. 3.1).
Because the fermentation curves of Hummel et al. (2008) are
reproduced in another chapter (Hummel & Clauss, this vol-
ume; see also Sander et al. 2010b), they will not be duplicated
here. However, I propose here a five-point scale categorizing
the amounts of gas production in order to describe qualita-
tively the relative amount of energy released from each food
plant type during the 72 hour long fermentation trials of
Hummel et al. (2008) and to facilitate comparison between
plant groups. Hence, excellent is over 45 ml/200 mg dry mat-
ter; very good is 35–45 ml/200 mg dry matter; good is 25–35
ml/200 mg dry matter; poor is 15–25 ml/200 mg dry matter;
and very poor is under 15 ml/200 mg dry matter.
Analysis of Plant Taxa
Habit and Habitat
The family Araucariaceae is represented today by three
genera—Araucaria (Plate 3.1), Agathis, and Wollemiaall of
which form tall evergreen trees. On average, the 20 or so spe-
cies of Araucaria reach heights of about 30 m, but A. hetero-
phylla, which is commonly grown in northern temperate re-
gions as a garden or house plant (i.e., the Norfolk Island pine),
can top out at 70 m (Krüssmann 1972). Mature trees of Arau-
caria (Plate 3.1F) or Agathis often occur singly as canopy domi-
nants in the forest, although Araucaria can also make up rela-
tively dense, monospecific groves of trees (Schütt et al. 2004).
All three genera occur in tropical and subtropical forests.
While Araucaria is native to both South America and Austra-
lasia, Agathis is widespread in Australasia (Krüssmann 1972),
and Wollemia is restricted to a single rain forest gorge near
Sydney, Australia (Jones et al. 1995).
Biomass Production
Like present-day members of the family, fossil Araucariaceae
formed tall trees, and their spreading branches probably con-
stituted quite a bit of biomass. In the past, as in the present,
these trees were likely slow growers; Araucaria plantations
in Northern Queensland, for example, take twice as long to
reach maturity as commercial timber like those with nonna-
tive pines (Hanrahan, pers. comm., 2007). When compared to
other tree species in its native habitat, Araucaria araucana is
also a slower grower. In a mixed Nothofagus forest in South
America, for example, the average increment of growth of
Araucaria araucana trees each year was only 5– 8.2 cm in height
Dietary Options for the Sauropod Dinosaurs 37
Paleogeographic map of the Late Jurassic (Kimmeridgian). Shown in black are the approximate locations of the three major
sauropod faunas discussed in this chapter. (1) Morrison Formation, Western Interior of North America. (2) Patagonia, southern South
America. (3) Tendaguru, Tanzania, Africa. Light gray indicates land; medium gray, highlands; and white areas within the black lines,
flooded shelves. Map modified after Smith et al. (2004).
and 2.3–2.7 mm in diameter (Donoso et al. 2004). Among the
southern conifers—that is, the Podocarpaceae, Araucariaceae,
and half of the Cupressaceae—Araucaria and Agathis are mod-
erate in their growth rate (Enright & Ogden 1995).
Potential for Recovery
All extant members of the Araucariaceae have the ability to
regenerate branches or treetops that have been broken off by
way of epicormic and coppice buds (e.g., Burrows 1990; Bur-
rows et al. 2003), which are, respectively, dormant buds on the
trunk or at the base of the tree that are triggered into produc-
ing new growth after damage (Plate 3.1G, H). This trait pro-
vides a way to continuously regenerate new organs resulting
from damage that may occur through drought, small-scale
fires, or blowdowns caused by tropical cyclones (e.g., Rigg et
al. 1998; Burrows et al. 2003; Gee, pers. obs.). In the Mesozoic,
this would have also been advantageous to the individual
trees after intense feeding on leafy branches and twigs by tall,
voracious sauropods, or damage by natural causes such as vol-
canic activity or fire. Indeed, fossil structures representing the
dormant woody buds of conifers such as Araucaria mirabilis
(Spegazzini) Windhausen or Pararaucaria patagonica Wieland
have been collected from the Middle Jurassic Cerro Cuadrado
Petrified Forest for many decades (Stockey 2002). It is thought
that these buds, called aerial lignotubers, may have developed
in the axils of leaves of conifers in this area in response to fire
caused by volcanism, which was a repeated occurrence in the
Cerro Cuadrado sequence (Stockey 2002).
The in vitro digestibility of Araucaria foliage, based on sev-
eral trials with five different species, is very good (Hummel et
al. 2008). Leaves and pollen cones (Plate 3.1B, D, E) of Arau-
caria are moderately good in their digestibility, while foliage of
Agathis is weakly digestible (Hummel, pers. comm.). In con-
trast to other plants, Araucaria foliage provides little in the
form of protein (Hummel et al. 2008; Hummel & Clauss, this
volume) and thus would be less appropriate for young, grow-
ing animals requiring a high protein intake. It should be noted
that herbivore gut fermentation behavior of Araucaria foliage
rises slowly in the first 30 hours of digestion, but finishes at a
relatively higher rate over the course of the next four days.
Such an energy release would be most advantageous to a large
animal with a long hindgut retention time, such as a giant-
sized adult sauropod dinosaur.
Consumption by Modern Herbivores
Although few vertebrates are known to feed on Araucaria,
there are reports of girdling (also known as ring barking) by
cockatoos in Northern Queensland, Australia (Hanrahan,
pers. comm. 2007). Araucaria seeds of the species that produce
large seeds, such as A. bidwillü, A. araucana, or A. angustifolia,
are commonly eaten by rats, by large birds such as cockatoos,
parrots, crows, or jays, and by humans.
Co-occurrence with Major Late Jurassic
Sauropod Faunas
Fossils pertaining to Araucaria occur throughout most of the
Mesozoic, starting from the Late Triassic and extending beyond
the Late Cretaceous; they were globally widespread as well. Spe-
cies diversity within just the genus Araucaria was high during
this era, judging from the more than 30 different species of seed
cones that have been described (Gee & Tidwell 2010). In the
Morrison Formation, araucarian plant compressions (e.g., Plate
3.1C) and wood are abundant and in fact are by far the most
common plant fossils in a sauropod bonebed, the Howe-
Stephens Quarry on the Howe Ranch in north-central Wyoming
(Gee & Tidwell 2010). Palynologically, araucariaceous pollen is a
major element throughout the Morrison Formation, second
only to the Cheirolepidiaceae in terms of frequency (Hotton &
Baghai-Riding 2010). In Patagonia, araucarian cones and trees
are locally very common, for example at the Cerro Cuadrado
Petrified Forest in Patagonia (e.g., Calder 1953; Stockey 1975,
1978; Zamuner & Falaschi 2005; Falaschi 2009). In Tendaguru,
araucarian cuticle occurs as a minor element of the flora, but the
family also shows up throughout the Dinosaur Beds in the form
of wood, as well as several species of abundant pollen (Schrank
1999; Aberhan et al. 2002) that suggest the widespread domi-
nance of araucarians, especially in the Middle Saurian Bed
(Schrank 2010).
Remarks and Rating
In the Mesozoic, the Araucariaceae, especially Araucaria,
would have been a good source of food for large herbivores such
as adult sauropods. Not only were araucarian trees common all
over the world during most of the Mesozoic, but as a conse-
quence of their arborescent growth habit and probable occur-
rence in forests, they would have provided large amounts of
biomass for consumption. By extrapolating from fermentation
experiments with extant Araucaria species, it can be inferred that
the foliage and cones of the Mesozoic araucarians would have
been high in energy and most suitable for large animals with a
long hindgut retention time. On the basis of these parameters
and because of the intimate association of Araucaria with sau-
ropods in bonebeds or in sediments coeval with the major sau-
ropod faunas, it is quite likely that the Araucariaceae were a
frequent and attractive source of food for the sauropods.
Habit and Habitat
The genus Equisetum (Plate 3.2A), commonly known as the
scouring rush or horsetail, is represented by about 15 species
today. All species are perennial, although those in temperate
areas often die back to the ground in the winter. Most temper-
ate species are low-growing, attaining a height of up to about
1 m, although one species in Chile, E. giganteum, reaches 5 m
(Husby 2003). Characteristic of all species in the genus is their
occurrence in large monospecific stands, which they achieve
by spreading underground with horizontal stems called rhi-
zomes. Because Equisetum can produce extensive root systems
to tap sources of deep groundwater, it grows in seemingly
parched, disturbed habitats, such as gravels along railroad
tracks or dry, sandy riverbeds, although it is common to find
extensive thickets of Equisetum in wet, marshy areas around
ponds or lakes, or along rivers.
Morphologically and anatomically, Equisetum has changed
very little since the Middle Triassic, down to the four strap-
shaped bands called elaters around its spores (Schwendemann
et al. 2010), which strongly suggests that it likely had the same
sort of growth habit and may have occupied the same sort of
moist habitats in the geological past as it does in the present
day. It is, for example, not uncommon to find numerous axes
of Jurassic Equisetum, such as E. laterale (Plate 3.2B), amassed
on one slab, which also suggests that this species grew in pure
stands in the Mesozoic as it still does today (Harris 1961; Gee
1989; Cantrill & Hunter 2005; Gee & Sander, pers. obs.).
Biomass Production and Potential for Recovery
Because the stem of Equisetum is basically a hollow cylinder,
each individual shoot is composed of relatively little biomass.
However, taking into account the low, thicket-like growth of
Equisetum, a large colony around a lake or several populations
on a floodplain could amount to quite a significant supply of
biomass for low-grazing herbivores.
Equisetum has a fast growth rate. Temperate species that die
back in the winter can produce a 1 m high shoot in a single
growing season. Gardeners are very familiar with the ability of
this plant to spread laterally in a relatively short period of time,
as well as with the difficulty of eradicating this weed because of
its extensive rhizome system. Similarly, damage to Equisetum
shoots—for example, due to herbivory—would not affect the
plant’s underground rhizomes and roots, which are protected
underground and would merely resprout new upright stems.
Digestibility and Consumption by Modern Herbivores
The energy yield of Equisetum, based on three species, is
excellent, exceeding that of all other plant groups, including
grasses (Hummel et al. 2008; Hummel and Clauss, this vol-
ume). Although silica is thought to hinder the digestibility of
cell walls (Van Soest 1994), the surface of Equisetum shoots,
which are rich in silica (e.g., Holzhüter et al. 2003), did not
seem to have much of a deleterious effect in the trials of Hum-
mel et al. (2008) and Hummel & Clauss (this volume). Further-
more, the digestibility of Equisetum rises very quickly within
Dietary Options for the Sauropod Dinosaurs 39
the first 24 hours, which suggests that smaller herbivores with
a shorter gut retention time would have especially benefited
from its consumption.
Despite possible negative effects of silica on digestion and
the purported abrasive effect of silica on mammalian teeth
(Sander, pers. comm.), several large herbivorous mammals in-
clude Equisetum as a key food plant in their diets. These include
caribou, moose, musk ox, dall sheep, and buffalo (Palmer
1944). Musk oxen, for example, commonly feed on horsetails
in the summertime, when they spend most of their time in
moist habitats (WMAC(NS) 2007). Similarly, many types of
waterfowl, such as Canada geese, lesser snow geese, pink-
footed geese, barnacle geese, and trumpeter swans, depend on
various species of Equisetum, especially during egg incubation
and after hatching (Thomas & Prevett 1982; Grant et al. 1994).
Even young birds, such as Icelandic pink-footed goslings, feed
extensively on E. arvense (Gardarsson & Sigurdsson 1972).
Trumpeter swan cygnets spend more time feeding on Equi-
setum than on submerged aquatic plants, as compared with
their parents (Grant et al. 1994). This is no wonder given the
high protein (22% dry weight) and high phosphorous content
of the rhizome tips and upright shoots of Equisetumthat is,
of E. fluvatilein late spring and summer (Thomas & Prevett
1982), when the needs for energy, protein, and minerals are at
their highest levels in geese (Thomas & Prevett 1982). In tropi-
cal regions, domestic cattle have been observed to graze on
Equisetum giganteum with relish (Hauke 1969).
Co-occurrence with Major Late Jurassic
Sauropod Faunas
Like Araucaria, Equisetum had a cosmopolitan distribution
in the Mesozoic from the Late Triassic onward, although there
are reports of the genus from the Carboniferous (Taylor et al.
2009). In the Late Jurassic of the Western Interior of North
America, several species of Equisetum have been reported from
Utah, Colorado, Wyoming, Montana, British Columbia, and
Alberta, including occurrences in sauropod bonebeds, such as
in the Mygatt-Moore Quarry in Colorado (Tidwell et al. 1998)
and the Howe-Stephens Quarry in Wyoming (Plate 3C; Gee,
unpublished data), or in beds that have yielded a typical as-
semblage of Morrison sauropods, namely, in the Como Bluff
‘‘Member’’ in Wyoming (Tidwell et al. 2006). At the last site,
Equisetum shoots are abundant and are represented by two
different species. In all cases, these shoots are slender and pre-
sumably pertain to short stems, attaining less than 1 m in
height. Several species of small-stature Equisetum have also
been described from Early Jurassic to mid Cretaceous floras
from both Patagonia (see recent summary by Villar de Seoane
2005; Falaschi et al. 2009) and the Antarctic Peninsula (e.g.,
Halle 1913; Gee 1989; Rees & Cleal 2004; Cantrill & Hunter
2005). Evidence of Equisetum has not yet been recovered from
the Tendaguru flora (cf. Aberhan et al. 2002; Schrank 2010).
Remarks and Rating
In the Mesozoic, Equisetum (or Equisetites, as it is also known),
would have been a good source of food for all low-browsing
herbivores, especially young sauropods. Given their global
distribution, these plants were probably common in fresh-
water wetland areas, where they likely covered large areas
along shorelines and in this way provided much biomass for
consumption. The plant’s characteristic vigorous growth of
aerial shoots, protection of its main stem underground, and
deep root system would have helped to quickly regenerate
stands of Equisetum after intense feeding by herbivores. Fer-
mentation experiments with extant Equisetum species by
Hummel et al. (2008) show that the aerial shoots as well as
the tips of the rhizome offer herbivores a high-energy source
of high protein, phosphorous, and other nutrient content
that would especially benefit young, fast-growing animals
such as young sauropods. The rapid digestibility of Equisetum
would have also been most advantageous to small or young
dinosaurs with a short gut retention time. Moreover, the short
stature of most horsetails in the past and their proximity
to sources of water would have enhanced their attractiveness
as a commonly sought-after food plant for young and smaller
Habit and Habitat
The family Cheirolepidiaceae is an extinct group of conifers
that was an important constituent of global floras during the
Mesozoic from the Late Triassic onward (Stewart & Rothwell
1993). In comparison to other conifer families, whether past
or present, the Cheirolepidiaceae show the greatest diversity
in regard to habit, habitat, and morphology. Some members
of the family were tall trees, for example, with a trunk diame-
ter up to about 1 m in one species (Francis 1983) or a height of
at least 23.4 m in another (Axsmith & Jacobs 2005). On the
basis of fossil wood studies on an in situ stand of cheirolepi-
diacean trees from the Late Jurassic of England, many of
the trees attained at least 200 years of age; the largest tree
was probably over 700 years old, indicating that there was a
lengthy history of continuity in this long-lived forest (Francis
1983). Although a nonarborescent habit is unusual among
conifers, other members of the Cheirolepidiaceae were herba-
ceous or scrubby, growing, for example, in low, dense stands
in a salt marsh setting (Jung 1974; Daghlian & Person 1977).
Cheirolepidiaceans grew in a variety of plant communities,
ranging from monospecific or low-diversity floras on hyper-
saline substrates or in brackish coastal swamps, to species-rich
assemblages in mesic, riparian settings (e.g., Daghlian & Per-
son 1977; Francis 1983; Gomez et al. 2002; Axsmith & Jacobs
2005); they thrived in warm habitats under semiarid or even
arid conditions, as well as in strongly seasonal climates (Fran-
cis 1983), especially at low paleolatitudes ([40\) during the
Cretaceous (Taylor et al. 2009 and references therein).
There are two major kinds of foliage in the Cheirolepidia-
ceae: leaves that are spirally arranged with either scale-like or
spreading leaves (Brachyphyllum or Pagiophyllum type) and
leaves that clasp around the shoot with a jointed appearance
(Frenelopsis and Pseudofrenelopsis type) (Watson 1988). Despite
this diversity in leaf morphology, traits that unify the family
(Watson 1988) are the distinctive pollen Classopollis and, to a
lesser extent, thick cuticles with sunken stomata and papillae
that extend over the stomata (Plate 3.2E). It is thought that
some species bore fleshy, succulent leaves (Watson 1988) and
that some species may have been deciduous (Behrensmeyer et
al. 1992).
Biomass Production and Potential for Recovery
The arboresent cheirolepidiaceans may have dominated the
woody vegetation in some areas, forming monospecific groves
or forests. In this case, their spreading branches and foliage
would have offered taller sauropods a large amount of bio-
mass. Similarly, the dense colonies of low-growing, halophytic
cheirolepidiaceans in the salt marshes of the Early Cretaceous
of Texas (Daghlian & Person 1977), which have a modern eco-
logical analog in the form of Salicornia (pickleweed), would
have also provided a plentiful source of food for small and
large sauropods alike. It is unknown how quickly cheirolepi-
diaceans grew or could regenerate after damage.
Digestibility and Consumption by Modern Herbivores
Because this group of plants does not have any close living
relatives, it is impossible to test foliage for digestibility, nor is it
possible to relate any accounts of consumption by modern
Co-occurrence with Major Late Jurassic
Sauropod Faunas
In the palynoflora of the Morrison Formation, Classopollis
pollen is extremely abundant in the southern states (New
Mexico and Arizona) and becomes increasingly less common
in the northern region (Hotton & Baghai-Riding 2010). Classo-
pollis pollen (also called Corollina) occurs throughout the Salt
Wash Member and older sediments at Dinosaur National
Monument in Utah (Litwin et al. 1998). Shoots with Brachy-
phyllum-type leaves bearing cuticle with papillae overhanging
the stomata occur at two sauropod bonebeds, the Mygatt-
Moore Quarry in Colorado (Tidwell et al. 1998) and the Howe-
Stephens Quarry in Wyoming (Gee, unpublished data); these
shoots likely pertain to the Cheirolepidiaceae. At Tendaguru,
both cuticle and pollen floras are dominated by the Cheiro-
lepidiaceae throughout most of the section, at times forming a
monotypical assemblage (Schrank 1999, 2010; Aberhan et al.
2002). The Cheirolepidiaceae have not yet been found in the
Jurassic of Patagonia, although the family does occur in the
Early Cretaceous of Argentina and Brazil as frenelopsid and
nonfrenelopsid foliage (Archangelsky 1963, 1966, 1968; Kunz-
mann et al. 2006).
Although the Cretaceous is technically beyond the scope of
this survey of co-occurrences, it is interesting to note that
Early Cretaceous cheirolepidiaceans occur in coastal sedi-
ments in Texas in which sauropod trackways and bonebeds
have been discovered. One species (Frenelopsis varians) was
collected from the Glen Rose Formation at a site northwest of
Austin, Texas, and grew in low colonies in salt marshes near a
hypersaline lagoon or bay depositional system (Daghlian &
Person 1977). A second species of Frenelopsis, F. ramosissima,
was found in a sauropod bonebed in the Twin Mountains For-
mation on the Jones Ranch southwest of Fort Worth and, in
contrast, formed a monospecific stand of massive trees in a
semiarid coastal forest (Axsmith & Jacobs 2005).
Remarks and Rating
Although the Cheirolepidiaceae no longer have any close
relatives on which we can run fermentation experiments or
measure biomass productivity, their habit as arborescent or
scrubby plants, dominance in xeric or saline habitats, and
general co-occurrence with sauropod during the mid and
late Mesozoic suggest that the members of this family have
constituted a major portion of a large sauropod’s diet. Fur-
thermore, as first pointed out by Tiffney (1997), their leaves,
which have a succulent appearance, may have been quite pal-
atable to the herbivorous dinosaurs.
Habit and Habitat
Ginkgo biloba (Plate 3.2F, G), the maidenhair tree, is the sole
surviving member of this group of plants, which once flour-
ished in the Northern Hemisphere during the Mesozoic and
Paleogene (Stewart & Rothwell 1993). Ginkgos are long-lived
trees that can survive up to 3,000 years (Del Tredici 1991)
and usually attain heights between 20 and 30 m, but can reach
60 m in height (Del Tredici 1991; Schütt et al. 2004). Some
shrubby forms may have existed in the Mesozoic (Green 2005,
2007). A distinctive trait of the maidenhair tree is its fan-
shaped leaves, which turn a brilliant golden color in the fall
(Plate 3.2G). Today, Ginkgo is deciduous, and it is commonly
assumed that ginkgophytes were deciduous in ancient times
too (e.g., Spicer & Parrish 1986). The natural distribution of
Ginkgo biloba is limited to a small, refugial area in southeastern
China, which has a mesic, warm-temperate climate (Del Tre-
dici 1992b). However, G. biloba is widely cultivated in areas
Dietary Options for the Sauropod Dinosaurs 41
with cold temperate, warm temperate, and Mediterranean cli-
mates (Del Tredici 2007), and is thus well known for its broad
environmental tolerance in regard to moisture, temperature,
and topography.
Biomass Production
Because of its economic importance in medicine, the har-
vesting of Ginkgo biloba leaves has received some attention,
especially in Asia. It was found on a 15 year old plantation in
central Korea that the above-ground biomass of Ginkgo, which
includes stem wood, stem bark, branches, and foliage, equaled
23,780 kg/ha (Son & Kim 1998). This falls within the range of
biomass values for 10–20 year old stands of conifers, which
vary from 15,000–70,000 kg/ha (Kimmins et al. 1985). The
foliage-only biomass on the Korean Ginkgo plantation made
up 10% of the above-ground tree biomass, which is consid-
ered a relatively large proportion (Son & Kim 1998).
In the leaf biomass experiments of Hummel & Clauss (this
volume) in which the distal 30 cm of foliage of various tree
species were stripped, dried, and weighed, Ginkgo biloba pro-
duced 8.8 3.0 g in dry matter, compared to an average of
4.2 1.6 for six different broad-leaved trees, an increase of
more than twice as much biomass for Ginkgo over the angio-
Potential for Recovery
As a deciduous gymnosperm, Ginkgo biloba sheds its leaves
every year, which means that it will renew its foliage annually
in any case. It also has two kinds of lignotubers—sometimes
called basal chichi and aerial chichi—that will propagate new
trunks or branches from the parent plant vegetatively in the
event of traumatic damage or changes in substrate stability
(Del Tredici 1992a, 1992b). In fact, a Ginkgo biloba growing in
the center of the atomic blast over Hiroshima, which had its
trunk completely destroyed in 1945, is survived by a new tree
that sprouted from its base by way of its basal lignotubers (Del
Tredici 1991). These dormant woody buds may be the key to
ginkgo’s longevity through the centuries as well as through
geological time, as reproduction by seeds appears to be mostly
unsuccessful, especially in closed-canopy forests (Del Tredici
1992a, 1992b, 2007). This is due in great part to seed predation
(see below) and to the low-light conditions in a closed forest.
It has been observed that the small natural populations of
Ginkgo on Tian Mu Shan near Hangzhou, China, occur today
on disturbance-generated microsites with soil erosion such as
on stream banks, rocky slopes, and edges of exposed cliffs.
A preference for disturbed habitats would have been advan-
tageous for the germination and establishment of new ginkgo
trees in the wake of any trampling, soil-churning sauropods
feeding on older ginkgo stands, although it would have taken
some decades before the ginkgo seeds and saplings grew into
good-sized trees.
Ginkgo biloba is a slow grower. In plantations in its native
habitat on Tian Mu Shan, China, and in Virginia, USA, the
average growth rate was 21 cm/yr and 34 cm/yr for trees 25 and
35 years old, respectively (Del Tredici 2004). A more vigorous
average growth rate of 48 cm/yr was measured on the 15 year
old plantation in Korea mentioned above (Son & Kim 1998).
Digestibility and Consumption by Living
Animals and Humans
In laboratory fermentation experiments (Hummel et al.
2008), the energy yield of Ginkgo biloba was found to be good.
Among the many plant groups tested by Hummel et al. (2008),
Ginkgo biloba leaves yielded by far the most crude protein, sur-
passing the percentage in dry matter of Equisetum (the next
best source of crude protein) by 1.3 times and that of arau-
cariaceous leaves (the worst source of crude protein among
the Mesozoic plant types tested) by 3.5 times (Hummel, pers.
The nutritious seeds of the extant ginkgo tree are consumed
by a number of different animals. Tree squirrels in North
America and China, such as the red-bellied squirrel on Tian
Mu Shan, feed on the ginkgo ‘‘nuts,’’ and humans, especially
in Asia, have eaten the boiled seeds for centuries (Del Tredici
1991). In addition, three omnivorous members of the Car-
nivora, the leopard cat and the masked palm civet in China
and the raccoon dog in Japan (Del Tredici 1992b, 2008), feed
on ginkgo ‘‘berries’—the inner seed surrounded by a fleshy,
foul-smelling seed coat. Indeed, the droppings of the raccoon
dog have been found to contain intact seeds, which then ger-
minated the next spring (Rothwell & Holt 1997). The feeding
of these nocturnal scavengers on ginkgo nuts has led Del Tre-
dici (1992b) to speculate that the foul-smelling seed coat of
Ginkgo attracts animal dispersers by posing as a carrion mimic.
In regard to its foliage, Ginkgo biloba is reputed to be quite re-
sistant to damage from insects, fungi, bacteria, and viruses (Del
Tredici 2004). Although there are some modern insects that
feed on Ginkgo leaves, their number is extremely small com-
pared to that attacking other gymnosperms (Honda 1997).
Consumption by Fossil Animals
In the Cretaceous–Paleogene boundary fossil flora in North
Dakota, the leaves of Ginkgo adiantoides show a few types of
insect damage (Labandeira et al. 2002).
Co-occurrence with Major Late Jurassic
Sauropod Faunas
Several species of Ginkgo leaves (Brown 1975; Ash & Tidwell
1998), as well as pollen (Hotton & Baghai-Riding 2010), occur
throughout the Morrison Formation, from Canada to Colo-
rado and Utah. Ginkgo seeds have been found in Utah and
Montana (Tidwell 1990b), while Ginkgo foliage co-occurs with
sauropod remains at the Mygatt-Moore Quarry in western
Colorado (Tidwell et al. 1998). At Tendaguru, ginkgo cuticle
does occur, but it is less commonly preserved than conifer
cuticle (Kahlert et al. 1999; Aberhan et al. 2002).
Remarks and Rating
The ginkgophytes would have been a good source of energy
and protein for medium-sized to large herbivores in the
Northern Hemisphere throughout the Mesozoic. As a conse-
quence of their arborescent growth habit and production of
abundant leaves, they would have provided much biomass for
consumption during times of the year when the trees bore
leaves. Moreover, mature trees with ginkgo nuts would have
provided taller sauropods with additional nutrition when
fruiting. The trees may have occupied more open or disturbed
habitats, which might have enabled larger animals more room
for maneuvering, and any damage to branches, the trunk, or
the base of the tree during feeding might have not perma-
nently harmed the tree, but instead activated its dormant
growth buds. Extrapolating from the good energy content of
Ginkgo biloba, as well as from the frequent association of
Ginkgo fossils and sauropod remains in the Late Jurassic Mor-
rison Formation, it is likely that Ginkgo leaves and its fructifi-
cations may have been a good, attractive source of nutrition
for larger herbivores in the Northern Hemisphere.
Habit and Habitat
The Podocarpaceae are a large family of mostly evergreen
conifers, consisting of about 18 genera and 170–200 species
(Hill 1995). Podocarpus is the largest genus in the family and
forms either trees from 20–30 m or occasionally 40 m in
height, or shorter, single- or multistemmed shrubs from 4–12
m in height (Krüssmann 1972). Most members of the family
are native to the warm temperate and subtropical zones of
the Southern Hemisphere, although a few species do occur
in Japan, China, Malaysia, and the Philippines (Krüssmann
1972). The taller trees can dominate the canopy layer in mid
to upper montane forests and can live longer than 1,000 years.
Podocarps are forest forming, as in New Zealand, where they
make up dense podocarp-dominated forests, as well as mixed
podocarp–hardwood forests (Ogden & Stewart 1995).
This family has a long history of plant megafossils and pol-
len extending back to the Early Triassic (Taylor et al. 2009).
Nearly all fossils occur in the Southern Hemisphere (Hill
1995), although there are a few reports of megafossils (e.g.,
from China; Zhou 1983) and pollen (e.g., from the Morri-
son Formation, USA; Hotton & Baghai-Riding 2010) from the
Mesozoic of the Northern Hemisphere as well. Although ex-
tant podocarps have free, spreading leaves, it should be noted
that podocarpaceous foliage described from the Mesozoic and
Cenozoic of Australasia resembles Brachyphyllum and Pagio-
phyllum (Gee, pers. obs. based on specimens figured by Hill
1995), which are two form genera with short leaves closely
appressed to the shoot axis that are common in the Mesozoic
floras all over the world.
Biomass Production and Potential for Recovery
In general, most members of the Podocarpaceae are very
slow growers, even when compared to other relatively slow-
growing conifers (Enright & Ogden 1995) or when growing
under benign conditions. For example, the net primary pro-
duction of a 35 year old plantation of Podocarpus imbricatus on
the tropical island of Hainan, China, averaged 10.3 metric
tons per hectare and year, reaching a maximum of 14 metric
tons per hectare and year (Chen et al. 2004). The former value
is much lower than the usual net primary production of tropi-
cal forests, and is instead roughly equivalent to that of warm
temperate forests (cf. Lieth 1975).
Some species of Podocarpus are known to possess epicormic
shoots, similar to those in the Araucariaceae.
Digestibility and Consumption by Modern Animals
The digestibility of three different genera (Podocarpus, Dacry-
dium, Phyllocladus) in this family proved to be poor (Hum-
mel, pers. comm.), and the family Podocarpaceae was one of
the worst plant groups in the experimental trials of Hummel et
al. (2008).
A fleshy tissue around podocarpaceous seeds called the epi-
matium (Plate 3.2H) adds to their attractiveness as a food op-
tion; such seeds are part of the normal diet of animals such as
brushtail opossums (Podocarpus hallii and Dacrydium cupressi-
num seeds) or ship rats (Prumnopitys ferruginea seeds) in mixed
podocarp–hardwood forests in New Zealand (Sweetapple &
Nugent 2007). The opossums rely on P. hallii as their main
food on both North Island and South Island of New Zealand
(Nugent et al. 1997 and references therein; Rogers 1997; Bell-
ingham et al. 1999). In fact, opossums bulk feed on the P. hallii
leaves all night when feeding in the canopy layer (Rogers
1997). Strangely, in the same mixed podocarp–hardwood for-
ests, P. hallii is avoided by browsing red deer. Indeed, red deer
in a temperate forest heavily dominated by Podocarpus nagii
also avoid eating podocarp leaves of this species, even in feed-
ing trials (Ohmae et al. 1996). This is thought to be due to
the antiherbivory effect of nagilactones in the leaves (Ohmae
et al. 1996).
Co-occurrence with Major Late Jurassic
Sauropod Faunas
As mentioned earlier, fossil shoots with leaves that have
been unequivocally identified as podocarpaceous elsewhere
resemble the form genera of Brachyphyllum and Pagiophyllum
that pertain to the foliage of the Araucariaceae and Cheiro-
Dietary Options for the Sauropod Dinosaurs 43
lepidiaceae. Several species of Brachyphyllum and Pagiophyllum
are known from the Morrison Formation (Tidwell 1990b; Ash
& Tidwell 1998; Tidwell et al. 1998, 2006), but none of them
have been assigned to the Podocarpaceae. In contrast, 16 form
taxa pertaining to podocarpaceous pollen have been de-
scribed from many parts of the Morrison Formation (Hotton
& Baghai-Riding 2010). The Podocarpaceae are also a com-
mon element in the Tendaguru flora, appearing in all or most
of the units as wood, cuticle, or pollen (Aberhahn et al. 2002;
Schrank 2010). In Patagonia, the Podocarpaceae first appear in
the Triassic (Troncoso et al. 2000) and continue to show up as
pollen, wood, leaves, and pollen and seed cones throughout
the Mesozoic (e.g., Del Fueyo 1996 on pollen; Gnaedinger
2007 on wood; Taylor et al. 2009 and references therein on
compression fossils).
Remarks and Rating
Assuming the Podocarpaceae had the same woody habits
and forest habitats in the Mesozoic as they do now, and con-
sidering their co-occurrence with the sauropod faunas, es-
pecially in the Southern Hemisphere, they would have been
a common food plant for herbivorous dinosaurs. However,
in view of their poor fermentation values, which translate
into comparatively low amounts of energy in each bite, slow
growth rates, and documented unpalatability to some large
present-day herbivores (red deer), the Podocarpaceae may
have been a less sought-after source of food compared to other
gymnosperms such as Araucaria, the Cheirolepidiaceae, and
Living conifers make up a large group of plants, called the
Pinophyta or Coniferae, consisting of 7 families, 69 genera,
and roughly 600 species (Earle 2009a). Two extant families
(Araucariaceae and Podocarpaceae) have been discussed here
separately as a result of their dominance in Mesozoic ecosys-
tems. The remaining families are the Cupressaceae, Pinaceae,
Taxaceae, Cephalotaxaceae, and Sciadopityaceae. It should also
be noted that the Taxodiaceae are now generally regarded as part
of the Cupressaceae, with the exception of Sciadopitys, which is
now commonly put into a separate family of its own. Because
the Taxaceae and Cephalotaxaceae have poor fossil records
and the Sciadopityaceae first appears in the Late Cretaceous
(Taylor et al. 2009), these families will not be treated here.
Habit and Habitat
The Cupressaceae comprise a large family that includes
about 27 genera and 127 species (Mabberley 1993) of shrubs
or, more commonly, trees, which can attain heights up to 112
m (Sequoia sempervirens, the coast redwood; Lanner 2002). The
trees in this family are also notable for being the largest (Se-
quoiadendron giganteum, the giant sequoia), the stoutest (Taxo-
dium mucronatum, the Montezuma cypress or ahuehuete), and
the second longest lived (Fitzroya cupressoides, the alerce) in
the world. The Cupressaceae are the most widely distributed
family of conifers and can be found on all continents except
for Antarctica (Earle 2009b). Accordingly, they are found in a
variety of habitats ranging from coastal settings, floodplains,
freshwater swamps (Plate 3.3A), riverbanks, and mountains,
and they thrive under various climatic regimes, which include
tropical, subtropical, warm temperate, and semiarid condi-
tions (Burns & Honkala 1990).
The oldest fossil generally accepted as pertaining to the
Cupressaceae occurs in the Middle Triassic (Yao et al. 1997). A
more solid fossil record of the family shows up in the Jurassic,
and the worldwide distribution of the Cupressaceae becomes
apparent in the Cretaceous (Taylor et al. 2009).
Biomass Production and Potential for Recovery
As large trees with spreading branches, like the other conifer
families described in this chapter, the members of the Cupres-
saceae offer quite a bit of biomass. Some members of the fam-
ily, such as Sequoia sempervirens, have such a high growth rate
that, of all the world’s vegetation types, a mature coast red-
wood forest produces the greatest biomass per unit area, even
exceeding that of tropical forests (Lanner 2002). In its first
year, a coast redwood sapling can grow up to 1.8 m in height
(Lanner 2002). Sequoiadendron giganteum, Metasequoia glypto-
stroboides, and Glyptostrobus pensilis are other examples of fast-
growing members of the family (Schütt et al. 2004).
Like araucarians and ginkgoes, some cupressaceous genera
have the capacity to regenerate from lignotubers, known in
many conifers as burls, after injury or death to the parent
tree. In the case of the coast redwood, for example, these dor-
mant growth buds are located along its roots, allowing it to
form lines of clones up to 30 m long after damage by fire
(Lanner 2002).
Digestibility and Consumption by Modern Animals
The in vitro fermentation of the Cupressaceae in the labora-
tory experiments of Hummel et al. (2008) was good. On the
basis of 11 samples from a variety of genera, the average
amount of digestibility nearly matches that of Ginkgo.
The wood of some cupressaceous trees, for instance, Juni-
perus virginia, Sequoia sempervirens, and Callitris glaucophylla,
can contain a compound that smells like camphor and deters
insects, especially termites. However, the foliage of the trees in
this family seems to be palatable to large herbivores. Juniperus
communis, J. occidentalis, J. californica, and Austrocedrus chilen-
sis are, for example, commonly heavily browsed by livestock
such as goats (e.g., Zanoni & Adams 1973; Torrano & Valder-
rábano 2005) and deer, especially red deer (Relva & Veblen
Co-occurrence with Major Late Jurassic
Sauropod Faunas
Foliage and wood of the Cupressaceae occurs in the Morrison
Formation (e.g., Tidwell 1990b; Ash & Tidwell 1998; Tidwell et
al. 1998). Wood assigned to the morphogenus Glyptostroboxy-
lon, which may pertain to the Cupressaceae/Taxodiaceae, is
also found at Tendaguru (Kahlert et al. 1999; Süss & Schultka
2001; Aberhan et al. 2002). In Argentina, cupressaceous wood
has been reported from the Jurassic (Gnaedinger 2004), and
leafy twigs with seed cones occur in the mid Cretaceous of
Argentina (Halle 1913; Archangelsky 1963; Villar de Seoane
1998; Llorens & Del Fueyo 2003; Del Fueyo et al. 2008).
The first convincing evidence of the Cupressaceae from the
Jurassic—a new genus and species (Austrohamia minuta) of
leafy twigs and branches bearing seed and pollen cones—was
recently described from Patagonia (Escapa et al. 2008).
Remarks and Rating
With an arborescent habit, spreading branches, the ability
to thrive in a variety of habitats, and good digestibility, the
trees of the Cupressaceae in the widest sense (that is, including
the basal members of the former Taxodiaceae) would have
been a good source of nutrition for the sauropod dinosaurs.
Taking into consideration their general co-occurrence with
the major sauropod faunas in both hemispheres, as well as the
palatability of cupressaceous leaves to extant herbivores, the
foliage of this conifer family may have comprised a good por-
tion of a herbivorous dinosaur’s diet.
Habit and Habitat
Like most conifers, the Pinaceae are predominantly ever-
green trees and are rarely deciduous or shrubs (Plate 3.3B);
they bear needle-like foliage and woody seed cones (Plate
3.3C). There are 9 genera and 194 species in this family, nearly
all of which are concentrated in the Northern Hemisphere
(Krüssmann 1972; Mabberley 1993). The Pinaceae form for-
ests, with most trees growing to a maximum height of 30 to
40 m, although a few can reach 87 m (Krüssmann 1972). This
family dominates the boreal forest—the world’s largest biome
—as well as most temperate and boreal mountain forests and
semiarid woodlands (Earle & Frankis 2009). Like the Cupressa-
ceae, the members of this family can also be found in coastal
settings (Plate 3.3B), in freshwater swamps, and on flood-
plains (Burns & Honkala 1990). Pinaceous trees have great
longevity; the longest lived organisms on earth, the bristle-
cone pines (Pinus longaeva and P. aristata), pertain to the
Pinaceae (Lanner 2002). The genera Abies (fir), Cedrus (cedar),
Larix (larch), Picea (spruce), Pinus (pine), Pseudotsuga (Douglas
fir), and Tsuga (hemlock spruce) are especially well known
because they are important sources of timber and pulp, tur-
pentine, resins, cultivated ornamentals, and edible seeds
(Mabberley 1993). Indeed, the family Pinaceae are economi-
cally and ecologically the most important gymnosperm fam-
ily on earth (Earle & Frankis 2009).
From the diversity of seed cones in the Cretaceous, it is
thought that the Pinaceae was well established early in the
Mesozoic (Taylor et al. 2009). One of the oldest members of
this family is represented by the seed cone Compsostrobus from
the Late Triassic of North Carolina (Delevoryas & Hope 1973,
Biomass Production and Potential for Recovery
Many trees in the Pinaceae exhibit a classical Christmas tree
shape, with long, downward-drooping branches. Combined
with their ability to form forests, this would offer much bio-
mass for browsing herbivores. Growth rates are variable in
the family. Early growth in Tsuga canadensis, for example, is
extremely slow, and trees with a d.b.h. (diameter at breast
height, a standard forester’s measurement) of less than 2.5 cm
(1 inch) may be as old as 100 years (Godman & Lancaster
1990). On the other hand, Pinus halepensis is a fast grower and
can attain a height of 30 cm in its first year (Schütt et al. 2004).
Regeneration in the Pinaceae is also variable. Although
some members of the family (e.g., Pinus virginiana) do not
show any resprouting (Carter & Snow 1990), many more re-
sprout readily in response to injury, particularly fire, sending
up new shoots from epicormic buds in the needle fascicles and
leaf axils, along the trunk, or from the roots. This latter group
includes species of Picea, Pinus, Pseudotsuga, and Tsuga (Earle &
Frankis 2009).
Digestibility and Consumption by Modern Herbivores
The digestibility of the Pinaceae in the in vitro fermentation
experiments of Hummel et al. (2008) is good.
Contrary to common belief, large herbivores such as forest
ungulates commonly feed on these conifers; they eat leaves,
strip bark, and tend to decimate saplings between 10 to 40 cm
high (e.g., Bergström & Bergqvist 1997; Kupferschmid & Bug-
mann 2005). For example, red deer, roe deer, and chamois feed
on Norway spruce (Picea abies) in European forests (Kupfer-
schmid & Bugmann 2005), while sika deer browse on young
Japanese larches (Larix kaempferi) in Japan (e.g., Akashi 2006).
A wide range of animals have been documented as feeding on
eastern hemlock (Tsuga canadensis), causing serious dam-
age, loss of vigor, slowing of growth rate, or death to the tree;
Dietary Options for the Sauropod Dinosaurs 45
these animals include white-tailed deer, snowshoe hares, New
England cottontails, mice, voles, squirrels and other rodents,
porcupines, and sapsuckers (Godman & Lancaster 1990).
White-tailed deer and rabbits are also known to browse on
young sprouts and seedlings of pitch pine (Pinus rigida; Little
& Garrett 1990). Meadow voles girdle young trees of Virginia
pine (Pinus virginiana), preferring it over other species in
the area (Carter & Snow 1990), and were responsible for dev-
astating seedling plantations of Norway spruce (Picea abies)
and Norway pine (Pinus resinosa) in Canada during a vole
population density peak in 1987–1988 (Bucyanayandi et al.
A number of species of Pinus produce large, edible seeds,
namely the pinyon pines and stone pine, which are eaten by
squirrels, a variety of birds, and humans. For instance, the
nutcracker and pinyon jays cache huge numbers of pinyon
pine seeds each year, which are eaten later by the birds in the
winter or left to germinate the coming spring (Lanner 2002).
In whitebark pine, uneaten seeds cached by Clark’s nutcrack-
ers are the only reliable means for the species to regenerate
itself (Lanner 2002). Even species of Pinus with smaller seeds,
such as P. rigida, are an important food for squirrels, quail, and
small birds such as the pine warbler, pine grosbeak, and black-
capped chickadee (Little & Garrett 1990).
Insect herbivory on seed cones is evident in the recent as
well as in the fossil record. Tunneled borings filled with frass
of boring beetles in a mid Cretaceous pinaceous seed cone
resemble the infestation of boring beetles of the genus Conoph-
thorus on seed cones of living Pinus spp., which eat through the
nutritive tissues of the vascular cambium, phloem, and cortex
of the cone (Falder et al. 1998).
Co-occurrence with Major Late Jurassic
Sauropod Faunas
Pinaceous foliage (commonly called Pityocladus or Pityophyl-
lum) and wood are known from the Late Jurassic Morrison For-
mation (Tidwell 1990b; Ash & Tidwell 1998). Bisaccate pollen
grains typical of this family are found throughout the Mor-
rison Formation as well (Hotton & Baghai-Riding 2010). Fossil
remains of the Pinaceae do not occur at Tendaguru or in Pata-
gonia, nor would it be expected to find them there because
this family had its main distribution in the Northern Hemi-
sphere during the Mesozoic, as it does today (Taylor et al.
Remarks and Rating
For the same reasons as in the Cupressaceae—a tree habit
with long, spreading branches, the ability to thrive in a num-
ber of different habitats, and good digestibility—the Pinaceae
would have been good food plants in the Mesozoic, albeit
only in the Northern Hemisphere.
Today, the ferns comprise a large division of plants, known as
the Filicophyta, containing some 20,000 species. Although
ferns can occur as epiphytes on trees or as floating macro-
phytes in freshwater, the ferns of interest here are ground-
dwelling forms with a long fossil history, such as the families
Marattiaceae and Osmundaceae.
Habit and Habitat
The Marattiaceae are a family of tropical ferns, with either
leaves arising near ground level from an underground rhi-
zome or elevated to the top of a tree-like trunk (Kramer et al.
1995). The 6 genera and roughly 260 species of this family
grow in rain forests under year-round uniform conditions
of high temperature and high humidity (Christenhusz 2009),
often in wet soils and shady spots (Jones 1987). The center of
diversity of the family today is in the Asian tropics (cf. Chris-
tenhusz et al. 2008).
The order Marattiales has an extensive fossil history that
extends back to the Early Carboniferous, about 300 million
years ago (Taylor et al. 2009), while fossil leaves identical to
those of the extant genera Marattia, Danaea, and Angiopteris
have been recorded as far back as the Late Triassic, Early Juras-
sic, and Middle Jurassic, respectively (e.g., Harris 1931; Hill
1987; Stewart & Rothwell 1993; Yang et al. 2008).
Biomass Production and Potential for Recovery
The largest member of the extant Marattiaceae, the king
fern Angiopteris evecta, produces large, robust fronds that can
reach lengths of 8 m. However, admittedly little is known
about its growth rate and longevity in its native habitat, al-
though it is under protection as an endangered species in parts
of Australia (NSW National Parks and Wildlife Service 2001).
Once established, the fronds of Angiopteris are massive and ro-
bust, although growth is presumably slow. Even under ideal
horticultural conditions, the propagation of Marattia by
spores, for example, proceeds at an extremely leisurely pace,
taking up to four years to produce a plant about 5 cm high
(Large & Braggins 2004).
Digestibility and Consumption by Modern Herbivores
The digestibility of Angiopteris evecta leaves is excellent, the
best of all the ferns tested by Hummel & Clauss (this volume),
and after 72 hours, it reaches the energy yield of grasses (Hum-
mel et al. 2008). Like Equisetum, the rate of fermentation of
Angiopteris is greatest within the first 24 hours of digestion.
There are reports of insect damage on living leaves of Marat-
tia and Angiopteris (Beck & Labandeira 1998), but it is not
known whether vertebrates also feed on these ferns today.
Co-occurrence with Major Late Jurassic
Sauropod Faunas
As mentioned above, fossils of Marattia, Danaea, and An-
giopteris are known from the Mesozoic, but they have not been
found in association with the major sauropod faunas from the
Morrison Formation, Tendaguru, or Patagonia.
Remarks and Rating
Although Angiopteris yields a remarkably high amount of
energy, especially for a fern, it is doubtful whether this genus,
along with Marattia and Danaea, formed a major part of a
giant sauropod’s diet. Not only would the general habitat of
marattiaceous ferns in dense, closed-canopy rain forests have
been less accessible to the larger sauropods, but the slow
growth and propagation of living marattiaceans also suggests
that there would have been a poor response of their Mesozoic
relatives to intense herbivore feeding pressure. Furthermore,
the lack of intimate association with major sauropod faunas
in the fossil record also suggests a lack of opportunities for
plant–herbivore interactions.
Habit and Habitat
The Osmundaceae are represented today by three genera
that form fronds near ground level (Osmunda, Plate 3.3D) or
sometimes at the top of tree-like stems (Todea, Plate 3.3E, and
Leptopteris). These ferns prefer moist, poorly drained condi-
tions in open or closed-canopy habitats such as stream banks,
damp woods, moist forests, and acidic swamps in temperate
and subtropical areas (Jones 1987; Kramer et al. 1995).
The family has an extensive fossil record, extending back to
the Permian (Stewart & Rothwell 1993). In Jurassic sediments,
osmundaceous rhizomes are abundant and occur all over the
world, but are most common in the Southern Hemisphere
(Tian et al. 2008). The existence of Osmunda and Todea in the
Middle Triassic and Late Cretaceous, respectively, document
the longevity of these genera (Jud et al. 2008). Indeed, one
living species (O. cinnamomea, the cinnamon fern in the east-
ern North America) has remained unchanged since the Late
Cretaceous (Serbet & Rothwell 1999).
Biomass Production and Potential for Recovery
The fronds of osmundaceous ferns range from relatively
small (less than 1 m long; Leptopteris) to moderately large (2–
4 m long; Osmunda and Todea). O. cinnamomea commonly
grows in monospecific colonies and, like Equisetum, can form
dense thickets.
Osmunda cinnamomea readily resprouts from its under-
ground rhizomes after its aerial portions have been destroyed
by fire, exhibiting vigorous rhizome growth after fire damage,
and in fact does best in areas that regularly experience burning
(Walsh 1994). Once established, individual plants of Osmunda
are reported to grow relatively fast, but it has also been noted
that the rate of vegetative spreading in Osmunda, Todea, and
Leptopteris is slow (Walsh 1994; Large & Braggins 2004).
Digestibility and Consumption by Modern
Herbivores and Humans
Osmunda and Todea have vastly different fermentation
curves. Osmunda is a good/excellent producer of energy, simi-
lar to grasses and forbs, while Todea is a poor producer of en-
ergy and has the second to worst fermentation curves (Hum-
mel, pers. comm.). Hence, a herbivore would be wiser in
regard to energy intake to graze on Osmunda than on Todea.
Livestock and white-tailed deer like to feed on Osmunda cin-
namomea, especially on tender fronds that are no older than a
month (Walsh 1994). In fact, cattle prefer to browse cinna-
mon ferns second only to cane (Arundinaria gigantea). Young
fronds of O. cinnamomea can also be steamed or boiled and
eaten by humans (Elias & Dykeman 1990).
Co-occurrence with Major Late Jurassic
Sauropod Faunas
Two genera of the Osmundaceae, the tree ferns Osmundacau-
lis and Ashicaulis (Tidwell & Rushfort 1970; Tidwell 1990a,
1994), occur in the Morrison Formation and are abundant near
Ferro and Moab in Utah (Tidwell 1990b), although the plant
remains are not directly associated with any sauropod remains.
Nevertheless, the spores of the family (Baculatisporites, Osmun-
dacites, and Todisporites) occur laterally and vertically through-
out the Morrison Formation (Litwin et al. 1998; Hotton &
Baghai-Riding 2010), indicating that they were part of the re-
gional vegetation. At Tendaguru, the spores of Todisporites and
Osmundacites show up in the palynoflora (Schrank 1999, 2010).
Although several species of osmundaceous rhizomes have
been reported from southernmost Patagonia, none of them
occur in the Late Jurassic (Tian et al. 2008). However, the form
genus Cladophlebis, which is thought to pertain to the Os-
mundaceae, occurs throughout the Triassic and Jurassic of Ar-
gentina and the Antarctic Peninsula (e.g., Herbst 1971; Gee
1989). Fossil Cladophlebis leaves (Plate 3.3F) are twice pinnate
and robust, closely resembling the fronds of extant Osmunda
(Plate 3.3D) and Todea (Plate 3.3E). Fertile pinnules known as
Todites bearing small, round, densely packed sporangia are
similar to the sporangia-bearing pinnules of living Todea.
Remarks and Rating
The Osmundaceae, especially Osmunda, may have formed a
recurrent but minor part of the sauropod diet in mesic habi-
Dietary Options for the Sauropod Dinosaurs 47
tats, given its high energy content, dense thicket-forming
habit, high palatability to some grazers and browsers, and co-
eval occurrence in the Morrison and Tendaguru sediments. If
a parallel can be drawn between the rapid regeneration of
fronds and the new colonization of disturbed areas after fire
in recent environments and sauropod herbivory in Mesozoic
times, Jurassic Osmunda rhizomes may have responded with
vigorous regrowth of their fronds after being cropped.
The Cycadales (the true cycads; Plate 3.3G) and Bennettitales
(also called the Cycadeoidales; Plate 3.3H) are two different
groups of gymnosperms with similar growth forms and leaf
morphology. These plants, which are commonly treated to-
gether as the cycadophytes, have pinnately compound leaves
that are so similar that at times they can only be distin-
guished from one another by details of epidermal features
such as stomata. The organization of their cones was very dif-
ferent, however, and this supports the continued separation
of the enigmatic Bennettitales from the Cycadales (cf. Crepet
& Stevenson 2010). Although cycads first showed up in the
Paleozoic and continue to the present day, bennettitaleans
occurred exclusively in the Mesozoic.
Habit and Habitat
Cycads have long, evergreen, pinnately compound fronds.
Their stems commonly form stout or tall, upright trunks and
are covered with a mantle of hard, woody leaf bases. There are
12 genera and over 300 species in the family (Chaw et al.
2005), and individual plants can live several hundred years.
Cycads occur today in the tropical, subtropical, and warm
temperate regions of both the Northern and Southern Hemi-
spheres, ranging northward from the southern islands of the
Japanese archipelago and southward to southern parts of Aus-
tralia, while the center of diversity of the cycads is in Central
America (Jones 1993). They can be found in mesic habitats,
such as rain forests, as well as in semiarid to xeric environ-
ments, such as grasslands and sparse woods, and on rocky
escarpments and in gorges (Jones 1993). Cycads have a long
fossil history that stretches back to the Carboniferous and
continues until today. They reached their heyday during the
Mesozoic in regard to geographic distribution and number of
taxa (Taylor et al. 2009).
The fronds of the bennettitaleans, on the other hand, look
similar to those of the cycads, but are commonly much shorter
in length. Their stems can appear stout and trunk-like, similar
to those of the cycads, or massively globose in shape. Like the
cycads, they were a characteristic feature of the landscape in
the Mesozoic. In Patagonia, for example, bennettitaleans were
shrubby plants that formed the understory vegetation along-
side corystosperms (a type of seed fern; see below) in a vari-
ety of forest types (evergreen, deciduous, sclerophyllous) or
grew in open areas as shrubs in the Triassic (Artabe et al. 2001;
Cúneo et al. 2010). In the Cretaceous of Patagonia, bennettita-
leans, as well as cycads, show morphological features adapted
to warm and seasonally dry climates, due at least in part to the
constant volcanic activity in the region (Archangelsky et al.
1995; Archangelsky 2003; Cúneo et al. 2010). Thus, like cy-
cads, bennettitaleans could grow in a variety of environments
ranging from mesic to xeric habitats.
Biomass Production and Potential for Recovery
Among gardeners and horticulturalists, cycads are notori-
ous for being slow growers. Cycads do not develop new leaves
continuously but produce a burst or flush of leaves at irregular
intervals in a tuft at the top of the trunk. Thus, young plants
often have few leaves and offer little in terms of biomass. The
amount of biomass contained in the leaves of an older plant
may be significantly higher, as cycad leaves tend to be per-
sistent, remaining on the plant for a long time.
As mentioned above, the leaves of the bennettitaleans were
shorter than those of modern cycads and would have thus
offered even less in terms of biomass. However, nothing is
known about the rate of growth in the bennettitaleans.
One cycad genus, Cycas, can reproduce itself vegetatively by
producing basal suckers, also known as bulbils or offsets, but
these also grow extremely slowly (Gee, pers. obs.). Other gen-
era, such as Encephalartos and Lepidozamia, have epicormic
buds in their trunks that will generate new growth if the plant
is damaged (Jones 1993).
As with most other extinct plant groups, nothing is known
about the potential for recovery and regrowth in the Ben-
Digestibility and Consumption by Modern
Herbivores and Humans
The fermentation experiments of Hummel et al. (2008)
show that cycad foliage is a poor producer of energy, vying
with the Podocarpaceae for the third-to-worst source of nutri-
tion for herbivores. Fermentation experiments could not be
run on the bennettitaleans because they do not have any liv-
ing relatives.
A major problem for herbivores feeding on cycads is the
presence of several strong toxins—macrozamin, cycasin, and
neocycasin, to mention a few—in various parts of the plants
(Hegnauer 1962). In Australia, the coordination of livestock
ingesting large quantities of the foliage or seeds of Bowenia,
Cycas, Lepidozamia, or Macrozamia becomes debilitated, and
the animals lose control of their hindlimbs (Jones 1993).
These ‘‘zamia staggers’’ happen mostly in cattle and sheep, but
also in horses, goats, and pigs. There are reports, however,
of some animals, namely emus, brush-tailed opossums, and
chuditch, that can ingest the seeds of Macrozamia riedlei,
which contain high levels of macrozamin, without ill effects
(e.g., Ladd et al. 1993).
Despite the occurrence of these highly poisonous com-
pounds, humans have long learned to neutralize the toxicity
in cycad seeds by roasting or leaching in preparation for hu-
man consumption (Hegnauer 1962; Jones 1993). Australian
aboriginals, for example, began utilizing Cycas and Macro-
zamia as a food source at least 13,000 years ago (Jones 1993).
Both the starch-filled seeds and the large starch reserves in
the pith of the trunks, known as sago or arrowroot, are har-
vested for making small loaves, cakes, or porridge (Jones
1993). Moreover, the roots of three species of ZamiaZ. boli-
viana, Z. lecontei, and Z. ulei—are used in Brazil for medicinal
purposes as an antidote to snakebite (Hegnauer 1962).
It is not known whether the bennettitaleans and Mesozoic
cycads contained the same abundance and range of toxins as
the living cycads.
Co-occurrence with Major Late Jurassic
Sauropod Faunas
There is a wealth of cycadophyte leaves throughout the
Morrison Formation, from southern Utah to southern Canada
(Tidwell 1990b; Ash & Tidwell 1998). Pollen, on the other
hand, occurs in very small amounts—less than 1% of the en-
tire sporomorph flora (Hotton & Baghai-Riding 2010)—and is
difficult to distinguish from that of ginkgophytes. In Tenda-
guru, minor amounts of cycadophyte wood and cuticle have
been reported (Kahlert et al. 1999).
In Patagonia, both cycads and bennettitaleans were integral
parts of the Mesozoic flora. In the Triassic, for example, cycado-
phytes are so common and rigorously constrained in their
stratigraphic occurrence that they can be used as biostrati-
graphic and chronostratigraphic markers (Spalletti et al. 1999;
Stipanicic 2002). Cycadophytes occur in the Early Jurassic but
are curiously absent in the Middle and Late Jurassic (Cúneo et
al. 2010), unlike elsewhere in the world, for example in the Late
Jurassic Morrison Formation, where they reach their climax. It
is instead in the Cretaceous when the cycadophytes reach their
peak of diversity and abundance in Patagonia, becoming ma-
jor components of the flora (Cúneo et al. 2010). A recent study
testing possible co-evolution between herbivorous nonavian
dinosaurs and cycads in the Late Triassic and in the Cretaceous
found no significant spatiotemporal correlation between these
two groups; nor did it find any unequivocal support for co-
evolutionary interactions (Butler et al. 2009, 2010).
Remarks and Rating
On the bases of the paucity of leaves borne by most cycads
and bennettitaleans, as well as their slow growth and leaf re-
generation, potentially high toxin content, and low energy
yield, cycads and possibly also the bennettitaleans were a poor
dietary option for sauropods. Given the common occurrence
of cycadophytes in the Mesozoic landscape in both hemi-
spheres, a cycadophyte may have been offered an occasional
biteful of leaves when encountered by a herbivorous dinosaur,
but it is doubtful that they were truly a staple of their diet.
Seed ferns, also known as pteridosperms, are not a natural
group of plants but are lumped together on the basis of their
fern-like foliage and seed-bearing habit. Like Ginkgo and the
conifers, they are considered gymnosperms because their
seeds are unprotected by an ovary or fruit. Although seed ferns
such as Medullosa and Glossopteris are well known from the
Paleozoic, a completely different suite of seed ferns thrived
during the Late Paleozoic–Mesozoic. This included the Cay-
toniales, Corystospermales, Petriellales, and Peltaspermales
(Taylor et al. 2006). Other enigmatic Mesozoic gymnosperms
are the Gigantopteridales, Vojnovskyales, Iraniales, Pentox-
ylales, Czekanowskiales, and Hermanophytales (Taylor et al.
2009). Because they are extinct, there is no information on
seed ferns in regard to biomass production, regrowth, digest-
ibility, and consumption by modern herbivores; however,
four of these orders—the Caytoniales, Corystospermales,
Czekanowskiales, and Hermanophytales—will be discussed
briefly here as a reminder that Mesozoic seed ferns also likely
formed a part of the sauropod diet.
Habit and Habitat
The Caytonia plant that bore the palmately compound
leaves of Sagenopteris may have been part of swamp vegetation
during Early Cretaceous times because it is associated with
lignites in the Kootenai Formation in Montana, which over-
lies the Late Jurassic Morrison Formation (LaPasha & Miller
1984). The Corystospermales, which grew primarily in Gond-
wana, were probably small to large woody shrubs (Taylor et al.
2009), although some of them may have been medium-sized,
unbranched, tree fern-like plants, or even had a scrambling
habit (Taylor et al. 2006).
The existence of the Czekanowskiales is known through
their leaves. Virtually nothing is known of growth forms in
this group, although some information on habitat preference
can be inferred from the fossil record. Czekanowskialean re-
mains occur with coals and floras rich in hydrophilic plants,
such as Equisetum and ferns, in the Morrison Formation and
elsewhere in the world, and suggest that Czekanowskia grew
under humid, temperate to tropical conditions (Ash 1994;
Tidwell 1990b; Ash & Tidwell 1998; Tidwell et al. 1998 and
references therein).
The Hermanophytales are an enigmatic group characterized
by permineralized stems with internal wedges of secondary
xylem (wood). Hermanophyton trunks range from 3 to 22.5 cm
Dietary Options for the Sauropod Dinosaurs 49
in diameter, measure over 18 m in length, and currently are
known from only four sites in the Morrison Formation (Ar-
nold 1962; Tidwell & Ash 1990; Tidwell 1990b, 2002; Ash &
Tidwell 1998). In regard to habit, it is thought that Herma-
tophyton may represent a small- to medium-sized, narrow-
stemmed tree with a crown of small leaves, or a long liana
(Taylor et al. 2009).
Co-occurrence with Major Late Jurassic
Sauropod Faunas
Three of the orders of seed ferns under discussion here have
been found in the Morrison Formation. The foliage of Cay-
toniarepresented by the form genus Sagenopterisoccurs in
the northern part of the Morrison Formation, in Belt, Mon-
tana (Brown 1972), as well as in the Early Cretaceous Kootenai
Formation in Montana (LaPasha & Miller 1985) and western
Canada (Bell 1956) which overlies the Morrison Formation.
Both Czekanowskia and Hermatophyton have been described
from several sites from the Morrison Formation (Ash 1994;
Tidwell 2002). The bisaccate pollen of the Caytoniales (Vitrei-
sporites type) and Czekanowskiales (Alisporites type) are also
represented in the Morrison Formation (Litwin et al. 1998;
Hotton & Baghai-Riding 2010).
At Tendaguru, bisaccate pollen of Alisporites that could per-
tain to the Corystospermales has been reported (Schrank 1999,
2010). However, fossil remains of the Caytoniales, Czekanow-
skiales, and Hermanophytales have not been found.
Within the region consisting of southern South America
and the nearby Antarctic Peninsula, Sagenopteris leaflets per-
taining to the Caytoniales have been described from the Ju-
rassic of Antarctica (Halle 1913; Gee 1989; Cantrill 2000),
although they have not been reported from Patagonia. How-
ever, as was mentioned earlier, the corystosperms were a major
element of the understory in Triassic forests of Patagonia,
alongside the bennettitaleans (Artabe et al. 2001; Cúneo et al.,
2010). Neither the Czekanowskiales nor the Hermanophytales
are known from Patagonia.
Remarks and Rating
Because Mesozoic seed ferns and other enigmatic gymno-
sperms were a distinctive component of Mesozoic floras, they
should not be overlooked in surveys of the Mesozoic flora.
However, because little is known about their palatability, nu-
tritional value, and ability to regrow after herbivory, it is diffi-
cult to evaluate their potential as a dietary option. They may
have played at least a minor role in the diets of large sauro-
pods, especially if they grew in more open areas.
As summarized in this chapter, a number of different variables
have been taken into account in the evaluation of plants as
sauropod fodder. Central to this discussion is the availability of
the individual plant groups to a large sauropod, which is re-
flected in part in the plant’s habit (growth form) and habitat
(environment in which it is found). Trees have the general
advantage of being able to offer more leaf biomass on their
spreading branches than smaller herbaceous plants such as
ferns. One exception is Equisetum; although herbaceous and
usually small in stature, horsetails have a fast growth rate and a
dense, colony-forming habit that boost their productivity and
biomass. In regard to habitat, plants that grew in more open
areas and not in dense forests would have theoretically been
more accessible to the larger sauropods, which would have had
problems maneuvering in tight spaces. Continuing this line of
thought, large conifers growing as solitary trees in open habi-
tats, in lightly wooded areas, or at the edge of a dense forest
would have been the most accessible to large sauropods.
Factors such as biomass production (growth rate) and po-
tential for recovery (regrowth of eaten plant parts) are also
important issues when assessing good long-term food sources.
Plants with low biomass production and low potential for re-
covery, such as the cycads and most ferns, are less likely to
serve as recurring food sources than plants with high biomass
production and greater potential for recovery. Examples of the
latter group include Equisetum, ginkgophytes, and conifers.
In this study, the potential for recovery not only means the
simple replacement of browsed plant parts, but also includes
the longevity of individual plants and taxa through geologic
time. To this end, it should be noted that a number of nearest
living relatives of the Mesozoic flora have dormant basal and/
or aerial buds that will grow and replace roots, stems, and
branches in the face of injury. This includes all of the living
gymnosperms under study here: Ginkgo, the Araucariaceae,
Podocarpaceae, Cupressaceae, and Pinaceae, and even the
Whether these dormant buds are called epicormic buds, cop-
pice shoots, aerial chichi, basal chichi, lignotubers, or burls,
woody plants with such dormant buds are known as sprouters
in the ecological literature and are common in both temperate
and tropical forests. The sprouting response leads to long-lived
individuals with long generation times that will preserve ge-
netic diversity, even in small populations (Bond & Midgley
2001). This is certainly the case in the living fossil Ginkgo and in
most of the conifer taxa discussed in this chapter.
Sprouters are resistant to disturbances and catastrophes
such as those caused by fire, hurricane damage, drought,
flooding, landslides, and herbivory (Bond & Midgley 2001).
Indeed, in modern ecosystems, it is thought that ‘‘sprouting
behavior might also be important in determining tree species
survival in the face of browsing by heavy mammals’’ (Bond &
Midgley 2001, p. 49). In this case, reference was being made to
the many species of savanna trees of a coppice in response
to damage caused by the largest herbivores on earth today, the
elephants. Assuming that sauropods fed on foliage, twigs, and
branches, and that they may have damaged tree trunks, bark,
and roots in their wake, being able to recover, regrow, and
resprout would have been advantageous for woody plants
during the Mesozoic.
Digestibility, which is quantified in the in vitro fermenta-
tion experiments of Hummel et al. (2008), and palatability,
which is reflected in part in the consumption of plant groups
by modern herbivores, are two more key factors. Although the
fermentation experiments were designed to reflect herbivore
hindgut digestion in general (Hummel & Clauss, this vol-
ume), the palatability of certain plants appears to be depen-
dent on the herbivore, as evidenced by the survey presented in
this chapter.
Most plant groups in this survey do co-occur with sauropods
in the areal extent of the three major sauropod faunas of the
Late Jurassic, which indicates that there were indeed opportu-
nities for herbivore–plant interactions at many sites. On the
basis of this brief review of co-occurrences, the most common
food options available in the Western Interior of North Amer-
ica (Morrison Formation), eastern Africa (Tendaguru), and
southern South America (Patagonia) would have been trees of
the Cheirolepidiaceae, Araucariaceae, and Podocarpaceae.
Comparative Rating of Plant Groups
By taking an integrated botanical and paleobotanical ap-
proach, it is clear that several plant groups would have been
good, accessible sources of food to the large sauropods in the
Mesozoic. Leading would be plants such as Equisetum, Arau-
caria, and the Cheirolepidiaceae, which were common in
Mesozoic ecosystems around the world and could offer much
biomass as fodder. These plants grew in thick stands around
freshwater (Equisetum) or brackish (Cheirolepidiaceae) bodies
of water, or as large trees in open forests (Araucaria, Cheiro-
lepidiaceae). Additional features attractive to sauropods may
have been the high energy content of Equisetum shoots and
rhizome tips, the unusual fermentation behavior of Araucaria
that yields more energy when retained in the hindgut for
longer periods of time (e.g., more than 30 hours), and the
succulence of the leaves of the Cheirolepidiaceae.
Although limited to the Northern Hemisphere, ginkgoes
may have been a good source of energy and especially pro-
tein. Similarly, conifers such as the Podocarpaceae and Cu-
pressaceae—and the Pinaceae to a lesser extent, due to their
Northern Hemisphere distribution—were convenient sources
of fodder, providing much biomass but fewer kilojoules per
mouthful than those plants mentioned above.
Because of their generally smaller stature and need for moist,
humid conditions such as those found in dense, closed forests,
most ferns would have been difficult for large sauropods to
encounter and ingest regularly. This would have included
Table 3.1. Likeliness of Mesozoic Plant Groups as a
Preferred Food Source for the Sauropod Dinosaurs
Plant group Rating Likeliness as a food source
Araucaria, Equisetum,
***** Very likely
Ginkgo **** Rather likely
Other conifer families
(e.g., Podocarpaceae,
Cupressaceae, Pinaceae)
*** Moderately likely
Ferns (e.g., Angiopteris,
** Less likely
Cycads and
* Least likely
Seed ferns, other
enigmatic gymnosperms
Unknown Cannot be evaluated at
this time
Angiopteris and Osmunda, which are excellent sources of energy
today. Fast-growing ferns that were better adapted to more
open areas under mesic conditions would have had to occur in
great abundance (the ‘‘fern prairies’’ of Taggart & Cross 1997,
for example) for a sauropod to make a meal of low-biomass
fronds of individual ferns.
Cycads were probably last on the list of desirable food op-
tions as a result of their low energy yield, low biomass produc-
tion, extremely slow growth rates, and high content of toxins.
However, because cycads (and bennettitaleans) were common
plants in open areas, sauropods may have occasionally in-
cluded them in their diet as well.
These plant groups can be compared to one another in re-
gard to their likelihood as a preferred dietary option or com-
monly eaten source of food for the large sauropod dinosaurs
(Table 3.1). Hence, taxa with five stars in Table 3.1 were most
likely to have been an accessible, dependable, plentiful, and
energy-producing food, while those with one star were the
least attractive as a food source. The relative ranking given in
Table 3.1 is offered as a baseline for future refinement and
This survey of the Mesozoic flora, which took into account
plant habit, habitat, biomass production, potential for recov-
ery, digestibility, consumption by modern herbivores, and co-
occurrence with sauropods in the Late Jurassic, revealed that
some plant groups were likely a more accessible, sustaining,
or preferred source of nutrition for the sauropod dinosaurs.
This included Araucaria, Equisetum, the Cheirolepidiaceae,
and Ginkgo. Sauropods were only moderately likely to browse
Dietary Options for the Sauropod Dinosaurs 51
other conifers, such as the Podocarpaceae, Cupressaceae, and
Pinaceae, and less likely to feed on forest-dwelling ferns such
as Angiopteris and Osmunda. The least likely eaten plants may
have been the cycads and bennettitaleans.
Sincere thanks are due to my colleagues in the DFG Research
Unit 533 for their helpful discussions, especially Martin Sander,
Jürgen Hummel (both at the University of Bonn), and Marcus
Clauss (University of Zurich), as well as to reviewers Bill Chal-
oner (University College London) and Jim Farlow (Purdue
University, Fort Wayne, Indiana) for their cogent remarks and
corrections. I am also indebted to Kerry Hanrahan (Atherton
Forestry Office, Forestry Plantations Queensland) for an
extensive, all-day tour through the Araucaria plantations and
to David Warmington (Cairns Botanic Garden, Cairns) for or-
ganizing a trip to see the northernmost natural population of
Araucaria bidwillii in northern Queensland, as well as to Hans
Hagdorn (Muschelkalkmuseum Ingelfingen) and Ted Delevor-
yas (University of Texas at Austin) for the use of their photos
of Osmunda and Cycadeoidea, respectively. This is contribu-
tion number 62 of the DFG Research Unit 533 ‘‘Biology of the
Sauropod Dinosaurs: The Evolution of Gigantism.’’
Aberhan, M., Bussert, R., Heinrich, W.-D., Schrank, E.,
Schultka, S., Sames, B., Kriwet, J. & Kapilima, S. 2002. Palaeo-
ecology and depositional environments of the Tendaguru Beds
(Late Jurassic to Early Cretaceous, Tanzania).—Mitteilungen aus
dem Museum für Naturkunde in Berlin, Geowissenschaftliche Reihe
5: 19–44.
Akashi, N. 2006. Height growth of young larch (Larix kaempferi)
in relation to the frequency of deer browsing damage in Hok-
kaido, Japan.—Journal of Forest Research 11: 153–156.
Archangelsky, A. 1963. A new Mesozoic flora from Ticó, Santa
Cruz Province, Argentina.—Bulletin of the British Museum (Natu-
ral History), Geology 8: 45–92.
Archangelsky, A., Andreis, R. R., Archangelsky, S. & Artabe, A. E.
1995. Cuticular characters adapted to volcanic stress in a new
Cretaceous cycad leaf from Patagonia, Argentina.—Review of
Palaeobotany and Palynology 89: 213–233.
Archangelsky, S. 1966. New gymnosperms from the Ticó flora,
Santa Cruz Province, Argentina.—Bulletin of the British Museum
(Natural History), Geology 13: 259–295.
Archangelsky, S. 1968. On the genus Tomaxellia (Coniferae) from
the Lower Cretaceous of Patagonia (Argentina) and its males
and female cones.—Journal of the Linnean Society (Botany) 61:
Archangelsky, S. (ed.). 2003. La Flora Cretácica del Grupo Baqueró,
Santa Cruz, Argentina. Museo Argentino de Ciencias Naturales,
Buenos Aires.
Arnold, C. A. 1962. A Rhenoxylon-like stem from the Morrison
Formation of Utah.—American Journal of Botany 49: 883–886.
Artabe, A., Morel, E. M. & Spalletti, L. A. 2001. Paleoecología de
las floras triásicas argentines. In Artabe, A. E., Morel, E. M. &
Zamuner, A. B. (eds.). El Sistema Triásico en la Argentina. Funda-
ción Museo La Plata, La Plata: pp. 199–225.
Ash, S. 1994. First occurrence of Czekanowskia (Gymnospermae,
Czekanowskiales) in the United States.—Review of Palaeobotany
and Palynology 81: 129–140.
Ash, S. R. & Tidwell, W. D. 1998. Plant megafossils from the
Brushy Basin Member of the Morrison Formation near Monte-
zuma Creek Trading Post, southeastern Utah.—Modern Geology
22: 321–339.
Axsmith, B. J. & Jacobs, B. F. 2005. The conifer Frenelopsis
ramosissima (Cheirolepidiaceae) in the Lower Cretaceous
of Texas: systematic, biogeographical, and paleoecological
implications.—International Journal of Plant Sciences 166:
Beck, A. L. & Labandeira, C. C. 1998. Early Permian insect foli-
vory on a gigantopterid-dominated riparian flora from north-
central Texas.—Palaeogeography, Palaeoclimatology, Palaeoecol-
ogy 142: 139–173.
Behrensmeyer, A. K., Damuth, J. D., DiMichele, W. A., Potts, R.,
Sues, H.-D. & Wing, S. L. (eds.). 1992. Terrestrial Ecosystems
through Time: Evolutionary Paleoecology of Terrestrial Plants and
Animals. University of Chicago Press, Chicago.
Bell, W. A. 1956. Lower Cretaceous floras of Western Canada.—
Geological Survey of Canada Memoir 285: 1–331.
Bellingham, P. J., Wiser, S. K., Hall, G. M. J., Alley, J. C., Allen,
R. B. & Suisted, P. A. 1999. Impacts of possum browsing on the
long-term maintenance of forest biodiversity.—Science for Con-
servation 103: 1–59.
Bergström, R. & Bergqvist, G. 1997. Frequencies and patterns of
browsing by large herbivores on conifer seedlings.—Scandina-
vian Journal of Forest Research 12: 288–294.
Bond, W. J. & Midgley, J. J. 2001. Ecology of sprouting in woody
plants: the persistence niche.—Trends in Ecology and Evolution
16: 45–51.
Brown, J. T. 1972. The Flora of the Morrison Formation (Upper Juras-
sic) of Central Montana. Ph.D. Dissertation. University of Mon-
tana, Missoula.
Brown, J. T. 1975. Upper Jurassic and Lower Cretaceous ginkgo-
phytes from Montana.—Journal of Paleontology 49: 724–730.
Bucyanayandi, J.-D., Bergeron, J.-M. & Menard, H. 1990. Prefer-
ence of meadow voles (Microtus pennsylvanicus) for conifer
seedlings: chemical components and nutritional quality of
bark of damaged and undamaged trees.—Journal of Chemical
Ecology 16: 2569–2579.
Burns, R. M. & Honkala, B. H. (eds.). 1990. Silvics of North Amer-
ica. 1. Conifers. Agriculture Handbook 654. USDA Forest Ser-
vice, Washington, D.C.
Burrows, G. E. 1990. Axillary meristem ontogeny in Araucaria
cunninghamii Aiton ex D. Don.—Australian Journal of Botany 34:
Burrows, G. E., Offord, C. A., Meagher, P. F. & Ashton, K. 2003.
Axillary meristems and the development of epicormic buds
in Wollemi Pine (Wollemia nobilis).—Annals of Botany
92: 835–844.
Butler, R. J., Barrett, P. M., Kenrick, P. & Penn, M. G. 2009. Testing
co-evolutionary hypotheses over geological timescales: inter-
actions between Mesozoic non-avian dinosaurs and cycads.—
Biological Reviews 84: 73–89.
Butler, R. J., Barrett. P. M., Penn, M. G. & Kenrick, P. 2010. Testing
evolutionary hypotheses over geological time scales: interac-
tions between Cretaceous dinosaurs and plants.—Biological
Journal of the Linnean Society 100: 1–15.
Calder, M. G. 1953. A coniferous petrified forest in Patagonia.—
Bulletin of the British Museum (Natural History), Geology 2: 99–
Cantrill, D. J. 2000. A new macroflora from the South Orkney Is-
lands, Antarctica: evidence of an Early to Middle Jurassic age for
the Powell Island conglomerate.— Antarctic Science 12: 185–195.
Cantrill, D. J. & Hunter, M. A. 2005. Macrofossil floras of the
Latady Basin, Antarctic Peninsula, New Zealand.—Journal of
Geology and Geophysics 48: 537–553.
Carter, K. K. & Snow, A. G., Jr. 1990. Pinus virginiana Mill., Vir-
ginia pine. In Burns, R. M. & Honkala, B. H. (eds.). Silvics of
North America. 1. Conifers. USDA Forest Service, Washington,
D.C.: pp. 513–519.
Chaw, S.-M., Walters, T. W., Chang, C.-C., Hu, S.-H. & Chen,
S.-H. 2005. A phylogeny of cycads (Cycadales) inferred from
chloroplast matK gene, trnK intron, and nuclear rDNA ITS
region.—Molecular Phylogenetics and Evolution 37: 214–234.
Chen, D.-X., Li Y.-D., Luo, T- S., Lin, M.-X. & Sun, Y.-X. 2004.
Study on biomass and net primary production of Podocarpus
imbricatus plantation in Jianfengling, Hainan Island.—Forest
Research, Chinese Academy of Forestry 17: 604–608.
Christenhusz, M. J. M. 2009. Danaea. January 23, 2009. Available
at: Accessed May 13, 2009.
Christenhusz, M. J. M., Tuomisto, H., Metgar, J. S. & Pryer, K. M.
2008. Evolutionary relationships within the Neotropical,
eusporangiate fern genus Danaea (Marattiaceae).—Molecular
Phylogenetics and Evolution 46: 34–48.
Coe, M. J., Dilcher, D. L., Farlow, J. O., Jarzen, D. H. & Russell,
D. A. 1987. Dinosaurs and land plants. In Friis, E. M., Chaloner,
W. G. & Crane, P. R. (eds.). The Origins of Angiosperms and Their
Biological Consequences. Cambridge University Press, Cam-
bridge: pp. 225–258.
Cúneo, N. R., Escapa, I., Villar de Seoane, L., Artabe, A. &
Gnaedinger, S. 2010. Review of the fossil cycads and bennet-
titaleans of Argentina. In Gee, C. T. (ed.). Plants in Mesozoic
Time: Morphological Innovations, Phylogeny, Ecosystems. Indiana
University Press, Bloomington: pp. 187–212.
Currie, P. J., Koppelhus, E. B. & Muhammad, A. F. 1995. ‘‘Stom-
ach’’ contents of a hadrosaur from the Dinosaur Park Forma-
tion (Campanian, Upper Cretaceous) of Alberta, Canada. In
Sun, A. & Wang, Y. (eds.). Sixth Symposium on Mesozoic Ter-
restrial Ecosystems and Biota, Short Papers. China Ocean Press,
Beijing: pp. 111–114.
Crepet, W. L. & Stevenson, D. W. 2010. The Bennettitales
(Cycadeoidales): a preliminary perspective on this arguably
engimatic group. In Gee, C. T. (ed.). Plants in Mesozoic Time:
Morphological Innovations, Phylogeny, Ecosystems. Indiana Uni-
versity Press, Bloomington: pp. 215–244.
Daghlian, C. P. & Person, C. P. 1977. The cuticular anatomy of
Frenelopsis varians from the Lower Cretaceous of central
Texas.—American Journal of Botany 64: 564–569.
Delevoryas, T. & Hope, R. C. 1973. Fertile coniferophyte remains
from the Late Triassic Deep River Basin, North Carolina.—
Americal Journal of Botany 60: 810–818.
Delevoryas, T. & Hope, R. C. 1987. Further observations on the
Late Triassic conifers Compsostrobus neotericus and Voltzia
andrewsii.Review of Palaeobotany and Palynology 51: 59–64.
Del Fueyo, G. 1996. Microsporogenesis and microgametogenesis
of the Argentinian species of Podocarpus (Podocarpaceae).—
Botanical Journal of the Linnean Society 122: 171–182.
Del Fueyo, G., Archangelsky, S., Llorens, M. & Cúneo, R. 2008.
Coniferous ovulate cones from the Lower Cretaceous of Santa
Cruz Province, Argentina.—International Journal of Plant Sci-
ences 169: 799–813.
Del Tredici, P. 1991. Ginkgos and people: a thousand years of
interaction.—Arnoldia 51: 3–15.
Del Tredici, P. 1992a. Natural regeneration of Ginkgo biloba from
downward growing cotyledonary buds (basal chichi).—
American Journal of Botany 79: 522–530.
Del Tredici, P. 1992b. Where the wild ginkgos grow.—Arnoldia 52:
Del Tredici, P. 2004. Ginkgo biloba Linné. In Schütt, P., Weis-
gerber, H., Schuck, H. J., Lang, K. J., Stimm, B. & Roloff, A.
(eds.). Lexikon der Nadelbäume. Nikol Verlagsgesellschaft, Ham-
burg: pp. 187–196.
Del Tredici, P. 2007. The phenology of sexual reproduction in
Ginkgo biloba: ecological and evolutionary implications.—
Botanical Review 73: 267–278.
Del Tredici, P. 2008. Wake up and smell the ginkgos.—Arnoldia
66: 11–21.
Donoso, C., Lara, A. & Alarcon, D. 2004. Araucaria araucana
(Mol.) K. Koch, 1795. In Schütt, P., Weisgerber, H.,
Schuck, H. J., Lang, K. J., Stimm, B. & Roloff, A. (eds.).
Lexikon der Nadelbäume. Nikol Verlagsgesellschaft, Hamburg:
pp. 93–98.
Earle, C. J. 2009a. Pinophyta. The Gymnosperm Database.
March 4, 2009. Available at:
pinales.htm. Accessed March 20, 2009.
Earle, C. J. 2009b. Cupressaceae. The Gymnosperm Database.
January 3, 2009. Available at:
index.htm. Accessed March 20, 2009.
Earle, C. J. & Frankis, M. 2009. Pinaceae. The Gymnosperm
Database. January 3, 2009. Available at: http://www.conifers
.org/pi/index.htm. Accessed April 30, 2009.
Elias, T. S. & Dykeman, P. A. 1990. Edible Wild Plants: A North
American Field Guide. Sterling Publishing, New York.
Enright, N. J. & Ogden, J. 1995. The southern conifers: a synthe-
sis. In Enright, N. J. & Hill, R. S. (eds.). Ecology of the Southern
Conifers. Smithsonian Institution Press, Washington, D.C.:
pp. 271–321.
Escapa, I., Cúneo, R. & Axsmith, B. 2008. A new genus of the
Cupressaceae (sensu lato) from the Jurassic of Patagonia:
implications for conifer megasporangiate cone homologies.—
Review of Palaeobotany and Palynology 151: 110–122.
Dietary Options for the Sauropod Dinosaurs 53
Falaschi, P. 2009. Sistemática, paleoecologia e indicaciones paleo-
climáticas de la tafoflora Monumento Natural Bosques Petrificados,
Jurásico Medio, Patagonia, República Argentinia. Ph.D. Disserta-
tion. Universidad Nacional de La Plata, Argentina.
Falaschi, P., Zamuner, A. B. & Foix, N. 2009. Una nueva Equisetal
fértil de la Formación La Matilde, Jurásico Medio, Argentina.—
Ameghinana 46: 263–272.
Falder, A. B., Rothwell, G. W., Mapes, G., Mapes, R. H. &
Doguzhaeva, L. A. 1998. Pityostrobus milleri sp. nov., a
pinaceous cone from the Lower Cretaceous (Aptian) of south-
western Russia.—Review of Palaeobotany and Palynology 103:
Francis, J. E. 1983. The dominant conifer of the Jurassic Purbeck
Formation, England.—Palaeontology 26: 277–294.
Gardarsson, A. & Sigurdsson, J. B. 1972. Research on the Pink-
footed Goose (Anser brachyrhynchus) in 1971. Other Studies in
Thjorsarver in 1971. Unpublished report, Icelandic National
Energy Authority Reykjavik, Iceland.
Gee, C. T. 1989. Revision of the Late Jurassic/Early Cretaceous
flora from Hope Bay, Antarctica.—Palaeontographica Abt. B 213:
Gee, C. T. & Tidwell, W. D. 2010. A mosaic of characters in a new
whole-plant Araucaria, A. delevoryasii Gee sp. nov., from the
Late Jurassic Morrison Formation of Wyoming, USA. In Gee,
C. T. (ed.). Plants in Mesozoic Time: Morphological Innovations,
Phylogeny, Ecosystems. Indiana University Press, Bloomington:
pp. 67–94.
Godman, R. M. & Lancaster, K. 1990. Tsuga canadensis (L.) Carr.
Eastern hemlock. In Burns, R. M. & Honkala, B. H. (eds.). Silvics
of North America. 1. Conifers. USDA Forest Service, Washington,
D.C.: pp. 604–612.
Gomez, B., Martín-Closas, C., Barale, G., Solé de Porta, N.,
Thévenard, F. & Guignard, G. 2002. Frenelopsis (Coniferales:
Cheirolepidiaceae) and related male organ genera from the
Lower Cretaceous of Spain.—Palaeontology 45: 997–1036.
Gnaedinger, S. 2004. Estudio preliminar de la xilotafoflora de la
Formación La Matilde (Jurásico Medio) del gran bajo de San
Julián, Santa Cruz, Argentina.—Comunicaciones Cientificas y
Tecnológicas, Universidad Nacional del Nordeste, SGCCyT, UNNE.
Gnaedinger, S. 2007. Podocarpaceae woods (Coniferales) from
Middle Jurassic La Matilde Formation, Sant Cruz province,
Argentina.—Review of Palaeobotany and Palynology 147: 77–93.
Grant, T. A., Henson, P. & Cooper, J. A. 1994. Feeding ecology of
trumpeter swans breeding in south central Alaska.—Journal of
Wildlife Management 58: 774–780.
Green, W. A. 2005. Were Mesozoic ginkgophytes shrubby? In
Popp, M. & Bolhar-Nordenkampff, H. (eds.). XVII International
Botanical Congress Abstracts, Vienna: p. 384.
Green, W. A. 2007. Using Leaf Architectural Data for Phenetic Eco-
logical Comparison of Modern and Fossil Forest Stands. Ph.D. Dis-
sertation. Yale University, New Haven.
Griebeler, E.-M. & Werner, J. This volume. The life cycle of sauro-
pod dinosaurs. In Klein, N., Remes, K., Gee, C. T. & Sander,
P. M. (eds.). Biology of the Sauropod Dinosaurs: Understanding
the Life of Giants. Indiana University Press, Bloomington:
pp. 263–275.
Halle, T. G. 1913. Some Mesozoic plant-bearing deposits in
Patagonia and Tierra del Fuego and their floras.—Kungliga
Svenska Vetenskapsakademiens Handlingar 51: 1–58.
Harris, T. M. 1931. The fossil flora of Scoresby Sound, East Green-
land. Part 1: Cryptogams (exclusive of Lycopodiales).—
Meddelelsler om Grønland 2: 1–102.
Harris, T. M. 1961. The Yorkshire Jurassic Flora. I. Thallophyta-
Pteridophyta. British Museum (Natural History), London.
Hauke, R. L. 1969. The natural history of Equisetum in Costa
Rica.—Revista de Biología Tropical 15: 269–281.
Hegnauer, R. 1962. Chemotaxonomie der Pflanzen. Band 1,
Thallophyten, Bryophyten, Pteridophyten und Gymnospermen.
Birkhäuser Verlag, Basel.
Herbst, R. 1971. Palaeophytología. III. 7. Revisión de las especies
argentinas del género Cladophlebis.—Ameghinana 8: 265–281.
Hill, C. R. 1976. Coprolites of Ptilophyllum cuticles from the Mid-
dle Jurassic of North Yorkshire.—Bulletin of the British Museum
(Natural History), Geology 27: 289–293.
Hill, C. R. 1987. Jurassic Angiopteris (Marattiales) from North
Yorkshire.—Review of Palaeobotany and Palynology 51: 65– 93.
Hill, R. S. 1995. Conifer origin, evolution and diversification in
the Southern Hemisphere. In Enright, N. J. & Hill, R. S. (eds.).
Ecology of the Southern Conifers. Melbourne University Press,
Carlton: pp. 10–29.
Holzhüter, G., Narayanan, K. & Gerber, T. 2003. Structure of sil-
ica in Equisetum arvense.Analytical and Bioanalytical Chemistry
376: 512–517.
Honda, H. 1997. Ginkgo and insects. In Hori, T., Ridge, R. W.,
Tulecke, W., Del Tredici, P., Trémouillaux-Guiller J. & Tobe, H.
(eds.). Ginkgo biloba, a Global Treasure: From Biology to Medicine.
Springer, Berlin: pp. 243–250.
Hotton, C. L. & Baghai-Riding, N. L. 2010. Palynological evi-
dence for conifer dominance within a heterogeneous land-
scape in the Late Jurassic Morrison Formation, USA. In Gee,
C. T. (ed.). Plants in Mesozoic Time: Morphological Innovations,
Phylogeny, Ecosystems. Indiana University Press, Bloomington:
pp. 295–328.
Hummel, J. & Clauss, M. This volume. Sauropod feeding and
digestive physiology. In Klein, N., Remes, K., Gee, C. T. &
Sander, P. M. (eds.). Biology of the Sauropod Dinosaurs: Under-
standing the Life of Giants. Indiana University Press, Bloom-
ington: pp. 11–13.
Hummel, J., Gee, C. T., Südekum, K.-H., Sander, P. M., Nogge, G.
& Clauss, M. 2008. In vitro digestibility of fern and gymno-
sperm foliage: implications for sauropod feeding ecology and
diet selection.—Proceedings of the Royal Society B: Biological Sci-
ences 275: 1015–1021.
Husby, C. 2003. How large are the giant horsetails? March 19,
2003. Available at: http:// GiantEquisetum/ HowLarge.html.
Accessed May 13, 2009.
Jones, D. L. 1987. Encyclopaedia of Ferns. British Museum (Natural
History), London.
Jones, D. L. 1993. Cycads of the World: Ancient Plants in Today’s
Landscape. Smithsonian Institution Press, Washington, D.C.
Jones, W. G., Hill, K. D. & Allen, J. M. 1995. Wollemia nobilis, a
new living Australian genus and species in the Araucariaceae.—
Telopea 6: 173–176.
Jud, N., Rothwell G. W. & Stockey, R. A. 2008. Todea from the
Lower Cretaceous of western North America: implications
for the phylogeny, systematics, and evolution of modern
Osmundaceae.—American Journal of Botany 95: 330–339.
Jung, W. 1974. Die Konifere Brachyphyllum nepos Saporta aus
den Solnhofener Plattenkalken (unteres Untertithon), ein
Halophyt.—Mitteilungen der Bayerischen Staatssammlung für
Paläontologie und Historische Geologie 14: 49–58.
Kahlert, E., Schultka, S. & Süß, H. 1999. Die mesophytische Flora
der Saurierlagerstätte am Tendaguru (Tansania). Erste
Ergebnisse.—Mitteilungen aus dem Museum für Naturkunde in
Berlin, Geowissenschaftliche Reihe 2: 185–199.
Kimmins, J. P., Binkley, D., Chatarpaul, L. & Catanzaro, J. de.
1985. Biogeochemistry of temperate forest ecosystems: litera-
ture on inventories and dynamics of biomass and nutrients.—
Canadian Forestry Service, Information Report PI-X-47E/ F.
Kramer, K. U., Schneller, J. J. & Wollenweber, E. 1995. Farne und
Farnverwandte. Georg Thieme Verlag, Stuttgart.
Krüssmann, G. 1972. Handbuch der Nadelgehölze. Paul Parey,
Kunzmann, L., Mohr, B. A. R., Bernardes-de-Oliveira, M. E. C. &
Wilde, V. 2006. Gymnosperms from the Early Cretaceous Crato
Formation (Brazil). II. Cheirolepidiaceae.—Fossil Record 9: 213–
Kupferschmid, A. D. & Bugmann, H. 2005. Effect of microsites,
logs and ungulate browsing on Picea abies regeneration in a
mountain forest.—Forest Ecology and Management 205: 251–
Labandeira, C. C., Johnson, K. R. & Lang, P. 2002. Preliminary
assessment of insect herbivory across the Cretaceous–Tertiary
boundary: major extinction and minimum rebound.—
Geological Society of America Special Paper 361: 297–327.
Ladd, P. G., Connell, S. W. & Harrison, B. 1993. Seed toxicity in
Macrozamia riedlei. In Stevenson D. W. & Norstog, K. J. (eds.).
Proceedings of CYCAD 90, the Second International Conference on
Cycad Biology. Palm and Cycad Societies of Australia, Milton:
pp. 37–44.
Lanner, R. M. 2002. Conifers of California. Cachuma Press, Los
Olivos, Calif.
LaPasha, C. A. & Miller, C. N., Jr. 1984. Flora of the Early Creta-
ceous Kootenai Formation in Montana, paleoecology.—
Palaeontographica Abt. B 194: 109–130.
LaPasha, C. A. & Miller, C. N., Jr. 1985. Flora of the Early Creta-
ceous Kootenai Formation in Montana, bryophytes and
tracheophytes.—Palaeontographica Abt. B 196: 111–145.
Large, M. F. & Braggins, J. E. 2004. Tree Ferns. Timber Press, Port-
land, Ore.
Lieth, H. 1975. Primary production of the major vegetation
units of the world. In Lieth, H. & Whittaker, R. H. (eds.). Pri-
mary Productivity of the Biosphere. Springer-Verlag, Berlin: pp.
Little, S. & Garrett, P. W. 1990. Pinus rigida, pitch pine. In Burns,
R. M. & Honkala, B. H. (eds.). Silvics of North America. 1. Con-
ifers. Agriculture Handbook 654. USDA Forest Service, Wash-
ington, D.C.
Litwin, R. J., Turner, C. E. & Peterson, F. 1998. Palynological evi-
dence on the age of the Morrison Formation, Western Interior
U.S.—Modern Geology 22: 297–319.
Llorens, M. & Del Fueyo, G. 2003. Coniferales fértiles de la forma-
ción Kachaike, Cretácico medio de la provincia de Santa Cruz,
Argentina.—Revista del Museo Argentino de Ciencias Naturales 5:
Mabberly, D. J. 1993. The Plant-Book. A Portable Dictionary of
the Higher Plants. Cambridge University Press, Cambridge.
Midgley, J. J., Midgley, G. & Bond, W. J. 2002. Why were the
dinosaurs so large? A food quality hypothesis.—Evolutionary
Ecology Research 4: 1093–1095.
Mohabey, D. M. 2005. Late Cretaceous (Maastrichtian) nests,
eggs, and dung mass (coprolites) of sauropods (titanosaurs)
from India. In Tidwell, V. & Carpenter, K. (eds.). Thunder-
Lizards. The Sauropodomorph Dinosaurs. Indiana University
Press, Bloomington: pp. 466–489.
NSW National Parks and Wildlife Service. 2001. Recovery Plan for
the Giant Fern (Angiopteris evecta). NSW National Parks and
Wildlife Service, Hurstville.
Nugent, G., Fraser, K. W. & Sweetapple, P. J. 1997. Comparison of
red deer and possum diets and impacts in podocarp–hardwood
forest, Waihaha Catchment, Pureora Conservation Park.—
Science for Conservation 50: 1–61.
Ogden, J. & Stewart, G. H. 1995. Community dynamics of the
New Zealand conifers. In Enright, N. J. & Hill, R. S. (eds.). Ecol-
ogy of the Southern Conifers. Smithsonian Institution Press,
Washington, D.C.: pp. 81–119.
Ohmae, Y., Shibata, K. & Yamakura, T. 1996. Seasonal change
in nagilactone contents in leaves in Podocarpus nagi forest.—
Journal of Chemical Ecology 22: 477–489.
Palmer, L. J. 1944. Food requirements of some Alaska game
mammals.—Journal of Mammalogy 2: 49–54.
Rees, P. M. & Cleal, C. J. 2004. Lower Jurassic floras from Hope
Bay and Botany Bay, Antarctica.—Special Papers in Palaeontology
72: 1–90.
Relva, M. A. & Veblen, T. T. 1998. Impacts of introduced large
herbivores on Austrocedrus chilensis forests in northern Pata-
gonia, Argentina.—Forest Ecology and Management 108: 27–40.
Rigg, L. S., Enright, N. J. & Jaffre, T. 1998. Stand structure of the
emergent Araucaria laubenfelsii, in maquis and rainforest,
Mont Do, New Caledonia.—Australian Journal of Ecology 23:
Rogers, G. 1997. Trends in the health of pahautea and Hall’s
totara in relation to possum control in central North Island.—
Science for Conservation 52: 1–49.
Rothwell, G. W. & Holt, B. 1997. Fossils and phylogeny in
the evolution of Ginkgo biloba. In Hori, T., Ridge, R. W.,
Tulecke, W., Del Tredici, P., Trémouillaux-Guiller, J. & Tobe, H.
(eds.). Ginkgo biloba, a Global Treasure: From Biology to Medicine.
Springer-Verlag, Berlin: pp. 223–230.
Sander, P. M. & Clauss, M. 2008. Sauropod gigantism.— Science
322: 200–201.
Dietary Options for the Sauropod Dinosaurs 55
Sander, P. M., Christian, A. & Gee, C. T. 2009. Sauropods kept
their heads down. Response.—Science 323: 1671–1672.
Sander, P. M., Gee, C. T., Hummel, J. & Clauss, M. 2010a. Meso-
zoic plants and dinosaur herbivory. In Gee, C. T. (ed.). Plants in
Mesozoic Time: Morphological Innovations, Phylogeny, Ecosystems.
Indiana University Press, Bloomington: pp. 331–359.
Sander, P. M., Christian, A., Clauss, M., Fechner, R., Gee, C. T.,
Griebeler, E. M., Gunga, H.-C., Hummel, J., Mallison, H.,
Perry, S., Preuschoft, H., Rauhut, O., Remes, K., Tütken, T.,
Wings, O. & Witzel, U. 2010b. Biology of the sauropod dino-
saurs: the evolution of gigantism.—Biological Reviews of the
Cambridge Philosophical Society. doi: 10.1111/j.1469–
Sander, P. M., Klein, N., Stein, K. & Wings, O. This volume. Sauro-
pod bone histology and its implications for sauropod biology.
In Klein, N., Remes, K., Gee, C. T. & Sander, P. M. (eds.). Biology
of the Sauropod Dinosaurs: Understanding the Life of Giants. Indi-
ana University Press, Bloomington: pp. 276–302.
Schrank, E. 1999. Palynology of the dinosaur beds of Tendaguru
(Tanzania)—preliminary results.Mitteilungen aus dem Museum
für Naturkunde in Berlin, Geowissenschaftliche Reihe 2: 171–183.
Schrank, E. 2010. Pollen and spores from the Tendaguru Beds,
Upper Jurassic and Lower Cretaceous of southeast Tanzania:
palynological and paleoecological implications.—Palynology
43: 3–42.
Schütt, P., Weisgerber, H, Schuck, H.-J., Lang, K. J., Stimm, B. &
Roloff, A. 2004. Lexikon der Nadelbäume. Hamburg, Nikol-Verlag.
Schwendemann, A. B., Taylor, T. N., Taylor, E. L., Krings, M. &
Osborn, J. M. 2010. Modern traits in Early Mesozoic spheno-
phytes: the Equisetum-like cones of Spaciinodum collinsonii with
in situ spores and elaters from the Middle Triassic of Antarc-
tica. In Gee, C. T. (ed.). Plants in Mesozoic Time: Morphological
Innovations, Phylogeny, Ecosystems. Indiana University Press,
Bloomington: pp. 15–33.
Serbet, R. & Rothwell, G. W. 1999. Osmunda cinnamomea
(Osmundaceae) in the Upper Cretaceous of western North
America. Additional evidence for exceptional species longevity
among filicalean ferns.—International Journal of Plant Sciences
160: 425–433.
Smith, A. G., Smith, D. G. & Funnell, B. M. 2004. Atlas of Meso-
zoic and Cenozoic Coastlines. Cambridge University Press,
Son, Y. & Kim, H.-W. 1998. Above-ground biomass and nutrient
distribution in a 15-year-old ginkgo (Ginkgo biloba) plantation
in central Korea.—Bioresearch Technology 63: 173–177.
Spalletti, L., Artabe, A., Morel, E. & Brea, M. 1999. Biozonación
paleoflorística y cronoestratigrafía del Triásico argentino.—
Ameghiniana 36: 419–451.
Spicer, R. A. & Parrish, J. T. 1986. Paleobotanical evidence for
cool north polar climates in middle Cretaceous (Albian–
Cenomanian) time.—Geology 14: 703–706.
Stewart, W. N. & Rothwell, G. W. 1993. Paleobotany and the Evolu-
tion of Plants. Cambridge University Press, Cambridge.
Stipanicic, P. N. 2002. Introducción.Revista de la Asociación
Geológica Argentina, B 26: 1–24.
Stockey, R. A. 1975. Seeds and embryos of Araucaria mirabilis.
American Journal of Botany 62: 856–868.
Stockey, R. A. 1978. Reproductive biology of Cerro Cuadrado fos-
sil conifers: ontogeny and reproductive strategies in Araucaria
mirabilis (Speg.) Windhausen.—Palaeontographica, Abt. B 166:
Stockey, R. A. 2002. A reinterpretation of the Cerro Cuadrado fos-
sil ‘‘seedings,’’ Argentina. In Dernbach, U. & Tidwell, W. D.
(eds.). Secrets of Petrified Plants, Fascination from Millions of
Years. D’ORO Publishers, Heppenheim: pp. 164 –171.
Süss, H. & Schultka, S. 2001. First record of Glyptostroboxylon
from the Upper Jurassic of Tendaguru, Tanzania.Botanical
Journal of the Linnean Society 135: 421–429.
Sweetapple, P. J. & Nugent, G. 2007. Ship rat demography and
diet following possum control in a mixed podocarp–hardwood
forest.—New Zealand Journal of Ecology 31: 186–201.
Taggart, R. E. & Cross, A. T. 1997. The relationship between land
plant diversity and productivity and patterns of dinosaur her-
bivory. In Wolberg, D. L., Stump, E. & Rosenberg, G. (eds.).
Dinofest. International Academy of Natural Sciences, Phila-
delphia: pp. 403–416.
Taylor, E. L., Taylor, T. N., Kerp, H. & Hermsen, E. J. 2006. Meso-
zoic seed ferns: old paradigms, new discoveries.—Journal of the
Torrey Botanical Society 133: 62–82.
Taylor, T. N., Taylor, E. L. & Krings, M. 2009. Paleobotany: The
Biology and Evolution of Fossil Plants. Academic Press, San
Thomas, V. G. & Prevett, P. J. 1982. The role of horsetails (Equi-
setaceae) in the nutrition of northern-breeding geese.—
Oecologia 53: 359–363.
Tian, N., Wang, Y.-D. & Jiang, Z.-K. 2008. Permineralized rhi-
zomes of the Osmundaceae (Filicales): diversity and tempo-
spatial distribution pattern.—Palaeoworld 17: 183–200.
Tidwell, W. D. 1990a. A new osmundaceous species (Osmun-
dacaulis lemonii n. sp.) from the Upper Jurassic Morrison For-
mation, Utah.—Hunteria 2: 3–6.
Tidwell, W. D. 1990b. Preliminary report on the megafossil
flora of the Upper Jurassic Morrison Formation.—Hunteria
2: 1–11.
Tidwell, W. D. 1994. Ashicaulis, a new genus for some species of
Millerocaulis (Osmundaceae).—Sida, Contributions to Botany 16:
Tidwell, W. D. 2002. The Osmundaceae: a very ancient group of
ferns. In Dernbach, U. & Tidwell, W. D. (eds.). Secrets of Petrified
Plants, Fascination from Millions of Years. D’ORO Publishers,
Heppenheim: pp. 134–147.
Tidwell, W. D. & Ash, S. R. 1990. On the Upper Jurassic stem Her-
manophyton and its species from Colorado and Utah, USA.—
Palaeontographica Abt. B 218: 77–92.
Tidwell, W. D. & Rushforth, S. R. 1970. Osmundacaulis wadei, a
new osmundaceous species from the Morrison Formation
(Jurassic) of Utah.—Bulletin of the Torrey Botanical Club 97:
Tidwell, W. D., Britt, B. B. & Ash, S. R. 1998. Preliminary floral
analysis of the Mygatt-Moore Quarry in the Jurassic Morrison
Formation, west-central Colorado.—Modern Geology 22: 341–
Tidwell, W. D., Connely, M. & Britt, B. B. 2006. A flora from the
base of the Upper Jurassic Morrison Formation near Como
Bluff, Wyoming, USA.—New Mexico Museum of Natural History
and Science Bulletin 36: 171–181.
Tiffney, B. H. 1997. Land plants as food and habitat in the age of
dinosaurs. In Farlow, J. O. & Brett-Surman, M. K. (eds.). The
Complete Dinosaur. Indiana University Press, Bloomington:
pp. 352–370.
Torrano, L. & Valderrábano, J. 2005. Grazing ability of European
black pine understorey vegetation by goats.—Small Ruminant
Research 58: 253–263.
Troncoso, A., Gnaedinger, S. & Herbst, R. 2000. Heidiphyllum,
Rissikia y Desmiophyllum (Pinophyta, Coniferales) en el Triasico
del norte chico de Chile y sur de Argentina.—Ameghiniana 37:
Van Soest, P. J. 1994. Nutritional Ecology of the Ruminant. Cornell
University Press, Ithaca.
Villar de Seoane, L. 1998. Comparative study of extant and fossil
conifer leaves from the Baqueró Formation (Lower Creta-
ceous), Santa Cruz Province, Argentina.—Review of Palaeo-
botany and Palynology 99: 247–263.
Villar de Seoane, L. 2005. Equisetites pusillus sp. nov. from the
Aptian of Patagonia, Argentina.—Revista del Museo Argentino de
Ciencias Naturales 7: 43–49.
Walsh, R. A. 1994. Osmunda cinnamomea. In Fire Sciences Labora-
tory (ed.). Fire Effects Information System. U.S. Department of
Agriculture, Forest Service, Rocky Mountain Research Station.
Watson, J. 1988. The Cheirolepidiaceae. In Beck, C. B. (ed.).
Origin and Evolution of Gymnosperms. Columbia University
Press, New York: pp. 382–447.
WMAC(NS). 2007. Muskox fact sheet number 5—habitat and
diet. Available at:
%20Fact%20Sheet%20Number%205.pdf. Accessed May 13,
Yang, S., Wang, J. & Pfefferkorn, H. W. 2008. Marattia agan-
zhenensis sp. nov. from the Lower Jurassic Daxigou Formation
of Lanzhou, Gansu, China.—International Journal of Plant Sci-
ences 169: 473–482.
Yao, X., Taylor, T. N. & Taylor, E. L. 1997. A taxodiaceous seed
cone from the Triassic of Antarctica.—American Journal of Bot-
any 84: 343–354.
Zamuner, A. B. & Falaschi, P. 2005. Agathoxylon matildense n. sp.,
leno araucariaceo del Bosques Petrificados del cerro Madre e
Hija, Formación La Matilde (Jurásico medio), provincial de
Santa Cruz, Argentinia.—Ameghinana 42: 339–346.
Zanoni, T. A. & Adams, R. P. 1973. Distribution and synonymy
of Juniperus californica Carr. (Cupressaceae) in Baja California,
Mexico.—Bulletin of the Torrey Botanical Club 100: 364–367.
Zhou, Z. 1983. Stalagma samara, a new podocarpaceous conifer
with monocolpate pollen from the Upper Triassic of Hunan,
China.—Palaeontographica Abt. B 185: 56–78.
Zhou, Z. & Zhang, F. 2002. A long-tailed, seed-eating bird from
the Early Cretaceous of China.—Nature 418: 405–409.
... In addition to producing abundant biomass, conifer needles commonly have high levels of lignin, low nutrient levels, lower decay rates, and higher probability of fossilization (Steart et al., 2009;Liu et al., 2014;Chae et al., 2019). Many conifers can regenerate swiftly if disturbed (e.g., fire disturbance) (Gee, 2011), and therefore abundance of conifers across all five sites could be an ecological response of successional recovery after fire disturbance, which the Gates Fm Flora likely experienced at 20-to 40-year intervals (Lamberson et al., 1996). ...
... The NMDS analysis (Fig. 7) grouped many fern genera closer to Sites 2 and 4, which suggests that these sites were likely suitable environments for fern growth, and thus likely high in moisture, recently disturbed, or boggy environments (Cremer and Mount, 1965;Howe and Cantrill, 2001;Van Konijnenburg-Van Cittert, 2002;Peppe et al., 2008;Gee, 2011). The NMDS analysis also grouped conifer taxa closer to Site 1, suggesting that this site may have been more distal to water bodies on the coastal plain, where a mature soil was able to form and support coniferous forests (Mendes et al., 2014), with an understory composed of ferns and Taeniopteris. ...
... This suggests that Borealopelta markmitchelli was preferentially consuming ferns, to the near exclusion of conifers, cycadophytes, Taeniopteris, Sagenopteris, Ginkgoites, and Equisetites. The difference could be due to palatability, opportunity, or both, as ferns are considered a soft palatable food source compared to conifers and cycadophytes and would also be in the hypothesized feeding height of 1 m or less (Stevens and Parrish, 2005;Gee, 2011;Mallon et al., 2013). Of course, the abundance of ferns observed in the cololite mesoflora could simply be the result of the animal feeding at a fern-rich locality prior to death, as our data do indicate variability in the distribution of ferns in the Gates Fm landscape. ...
Full-text available
During the Cretaceous, large herbivorous dinosaurs (megaherbivores) acted as keystone species—just as large mammals do today (e.g., elephants)—yet despite their significance in Cretaceous ecosystems, what plant taxa these dinosaurs ate is unclear. The Albian armoured dinosaur Borealopelta markmitchelli (Ornithischia; Nodosauridae) was discovered in northern Alberta, Canada and has well-preserved stomach contents dominated by fern leaf tissues, with low amounts of gymnosperm material, implying selective feeding. The lower Albian Gates Formation (Grande Cache Member) macroflora of central Alberta is contemporaneous and spatially proximal with B. markmitchelli and therefore provides information on local vegetation available to this nodosaurid and other megaherbivores in this area. In this study we provide census-sampled abundance data for the Gates Formation macroflora. These data also provide the means to further investigate the feeding ecology of Borealopelta by summarizing the vegetation and local food options available. Census collections at five sites within the Grande Cache Member exposed in the Grande Cache Coal Mine reveal that the local vegetation there was dominated by conifers (44–70%) across all sites. Athrotaxites, Elatides, and Pityocladus were the most common conifers. Other gymnosperms present were ginkgophytes (e.g., Ginkgoites; 11%) and Taeniopteris (9%). Caytoniales (Sagenopteris) were found at one study site but uncommon (2%). Ferns (e.g., Cladophlebis, Coniopteris, Gleichenites) accounted for 14% of the total site counts while cycadophytes (Bennettitales; 4%) and Equisetites (1%) were less common. When comparing the Gates Formation macroflora to the stomach contents of Borealopelta, these data suggest that B. markmitchelli was selectively feeding on ferns, or in a recently disturbed fern-dense area within the local landscape.
... (38%) it is likely that the restriction of Sagenopteris to Site 5 is influencing both the cluster and NMDS analysis and separating this site from the other sites. Conifers produce abundant biomass, and many conifers can regenerate easily if disturbed (e.g., by fire etc.) (Gee, 2011). The high abundance of Athrotaxites and Elatides seen here are consistent with this area being in successional recovery after recent fire, which the Gates Fm likely experiences at a 20-40-year interval (Lamberson et al., 1996). ...
... As seen in Fig. 7, The NMDS analysis clustered many fern genera around Site 2 and Site 4, which indicates that these sites were suitable environments for fern growth; likely high in moisture, recently disturbed, or boggy environments (Cremer & Mount, 1965;Gee, 2011;Howe & Cantrill, 2001;Peppe et al., 2008;Van Konijnenburg-Van Cittert, 2002). The NMDS analysis also clusters conifer taxa around site 1. ...
... Previous studies hypothesizing dinosaur diet based on energy and nutrient content indicated that ferns would not be the most desirable plant group for a low-browsing megaherbivores and instead Equisetum should have been preferred (Gee, 2011;Gill et al., 2018;Hummel et al., 2008). Although Equisetites was present in the Gates Fm and growing at B. ...
During the Cretaceous, large herbivorous dinosaurs (megaherbivores) acted as keystone species—just as large mammals do today (e.g., elephants)—yet despite their significance in Cretaceous ecosystems, what plant taxa these dinosaurs ate is unclear. The Albian armoured dinosaur Borealopelta markmitchelli (Ornithischia; Nodosauridae) was discovered in northern Alberta, Canada and has well-preserved stomach contents dominated by fern leaf tissues, with only trace amounts of gymnosperm material, implying selective feeding. The Lower Albian Gates Formation (Grand Cache Member) macroflora of central Alberta is contemporaneous and spatially proximal with B. markmitchelli and therefore provides information on local vegetation available to this nodosaur and other megaherbivores in this area. In this study we provide unbiased abundance data for the Gates Fm macroflora. These data also provide the means to further investigate the feeding ecology of Borealopelta by summarizing the vegetation and local food options available. Census collections at five sites within the Grande Cache Mbr exposed in the Grande Cache Coal Mine reveal that the local vegetation there was dominated by conifers (44–70%) across all sites. Athrotaxites, Elatides, and Pityocladus were the most common conifers. Other gymnosperms present were ginkgophytes (e.g., Ginkgo, Ginkgoites; 11%) and Taeniopteris (9%). Caytoniales (Sagenopteris) were found at one study site but uncommon (2%). Ferns (e.g., Cladophlebis, Coniopteris, Gleichenites) accounted for 14% of the total site counts while cycadophytes (Bennettitales; 4%) and Equisetites (1%) were less common. When comparing the Gates Fm macroflora to the stomach contents of Borealopelta, these data suggest that B. markmitchelli was selectively feeding on ferns or in a recently disturbed fern-dense area within the local landscape.
... Previous research interpreted these morphological specializations with low-browsing feeding. The diet of diplodocoids with narrow-crowned teeth has been hypothesized to largely consist of abrasive plants, although the exact food differs [4,46,[49][50][51]]. An analysis of snout shape and microwear of diplodocoids found evidence for multiple feeding strategies, ranging from low to medium browse and both selective and non-selective diets [4]. ...
... The plant genus Equisetum (i.e. horsetail) was suggested to be an excellent potential food source in the Morrison Formation environment, in fact it yields energy levels that surpass extant grasses, but a noteworthy downside is that its surfaces are rich in silica [50,52]. Simple teeth that are rapidly replaced due to extensive wear may be an adaptation to an exceptionally abrasive diet [50], but this stands in stark contrast to the complex dentitions found in the vast majority of herbivorous mammals, squamates, and extinct crocodyliforms [27,29,41,42]. ...
... horsetail) was suggested to be an excellent potential food source in the Morrison Formation environment, in fact it yields energy levels that surpass extant grasses, but a noteworthy downside is that its surfaces are rich in silica [50,52]. Simple teeth that are rapidly replaced due to extensive wear may be an adaptation to an exceptionally abrasive diet [50], but this stands in stark contrast to the complex dentitions found in the vast majority of herbivorous mammals, squamates, and extinct crocodyliforms [27,29,41,42]. Complex teeth provide a greater surface area that breaks down plant material prior to ingestion, facilitating the absorption of nutrients. ...
Full-text available
Background Dinosaurs dominated terrestrial environments for over 100 million years due in part to innovative feeding strategies. Although a range of dental adaptations was present in Late Jurassic dinosaurs, it is unclear whether dinosaur ecosystems exhibited patterns of tooth disparity and dietary correlation similar to those of modern amniotes, in which carnivores possess simple teeth and herbivores exhibit complex dentitions. To investigate these patterns, we quantified dental shape in Late Jurassic dinosaurs to test relationships between diet and dental complexity. Results Here, we show that Late Jurassic dinosaurs exhibited a disparity of dental complexities on par with those of modern saurians. Theropods possess relatively simple teeth, in spite of the range of morphologies tested, and is consistent with their inferred carnivorous habits. Ornithischians, in contrast, have complex dentitions, corresponding to herbivorous habits. The dentitions of macronarian sauropods are similar to some ornithischians and living herbivorous squamates but slightly more complex than other sauropods. In particular, all diplodocoid sauropods investigated possess remarkably simple teeth. The existence of simple teeth in diplodocoids, however, contrasts with the pattern observed in nearly all known herbivores (living or extinct). Conclusions Sauropod dinosaurs exhibit a novel approach to herbivory not yet observed in other amniotes. We demonstrate that sauropod tooth complexity is related to tooth replacement rate rather than diet, which contrasts with the results from mammals and saurians. This relationship is unique to the sauropod clade, with ornithischians and theropods displaying the patterns observed in other groups. The decoupling of herbivory and tooth complexity paired with a correlation between complexity and replacement rate demonstrates a novel evolutionary strategy for plant consumption in sauropod dinosaurs.
... Dental complexes of sauropod dinosaurs have been studied in Diplodocidae, Rebbachisauridae, and Camarasauridae (D'Emic et al., 2013;Schwarz et al., 2015;Sereno et al., 2005;Stevens and Parrish, 2005) demonstrating that dental morphology and physiology (i.e., tooth and alveolar arrangement and tooth replacement strategies) directly impact feeding, digestion, and even food procurement. As such, these dental systems can provide considerable insight into sauropod paleobiology and paleoecology (e.g., Barrett and Upchurch, 1995;Fiorillo, 1998;Gee, 2011;McHugh, 2018;Tütken, 2011). ...
... Dietary habits and adaptations in sauropods have dominantly been studied through the lenses of rates of tooth replacement, neck biomechanics, tooth microwear, snout shapes, species richness, and estimates of population densities (e.g., Barrett and Upchurch, 1995;D'Emic et al., 2013;Fiorillo, 1998;Gee, 2011;McHugh, 2018;Schwarz et al., 2015;Sereno et al., 2005;Stevens and Parrish, 2005;Tütken, 2011;Whitlock, 2011;Whitlock et al., 2018). These studies reveal a wide range of diet-linked morphologies among different taxa; however, variance in the number of replacement teeth observed in the premaxilla, maxilla, and dentary among apatosaurine sauropods has yet to be fully investigated. ...
Full-text available
Dental complexes of sauropod dinosaurs have been studied in members of Diplodocoidea and Macronaria. However, the disparity among the number of replacement teeth between the premaxilla, maxilla, and dentary of apatosaurine sauropods has yet to be fully investigated. TATE-099, a nearly complete and associated apatosaurine skull and dental complexes from the upper Morrison Formation (Upper Jurassic) at Como Bluff, Wyoming, contains cranial characters consistent with Apatosaurus sp. Unerupted dental complexes of the right premaxilla, maxilla, and dentary were imaged and digitally reconstructed using computed tomography (CT). Results indicate four premaxillary alveolar positions each with 5-7 unerupted replacement teeth, 10 maxillary alveolar positions each with 3-5 unerupted replacement teeth, and 10 dentary alveolar positions each with only 1-2 unerupted replacement teeth. The capacity of replacement teeth in TATE-099 is higher than reported in the genus Diplodocus and consistent with data from previous studies on niche partitioning among coeval Morrison Formation sauropods. Disparity among the capacity of dental complexes of TATE-099 further suggests novel feeding mechanics in apatosaurines. CT data also support a new hypothesis of tooth replacement in diplodocids, where entire rows of teeth are replaced as a single unit, rather than individually. The high-capacity of replacement teeth in the premaxilla is only known to be succeeded by one taxon (Nigersaurus) and suggests frequent wear of the premaxillary teeth. However, considerably fewer replacement teeth in the dentary of TATE-099 suggests less-frequent. These results offer insight into the feeding mechanisms and disparity of sauropods within Flagellicaudata.
... It is therefore plausible to assume that at least species of Araucaria, and possibly also Pinus, provided emergent canopies in the uplands of northwestern Europe, suitable for high-browsing sauropods but out of reach -to our current knowledge -for ornithopods (see also Gee 2011 ...
Full-text available
A fragmentary centrum of a dorsal vertebra and a manual ungual phalanx of eusauropod dinosaurs from the Upper Barremian-Lower Aptian of Balve in western Germany are described. The dorsal centrum shares potential synapomorphies with the enigmatic genus Ornithopsis and can probably be referred to a titanosauriform. The Balve record is of significance as it represents the only known direct evidence of this clade from an upland environment in Europe, which is assumed to have reached palaeoelevations of several hundred meters above sea level. Taphonomic signatures at some of the material from this site indicate prolonged surface exposure plus various stages of wear caused by water transport. The remains were finally deposited in sediment traps within a karst cave or fissure system. The fossil record suggests a retreat or shift of sauropod habitat range from coastal plains and lowlands to hinter-and uplands during the Early Cretaceous in northwest Europe. It is hypothesized that this was linked to the faunal replacement of low-and mid-level browsing sauropods (e.g. diplodocoideans) by iguanodontian ornithopods near the Jurassic-Cretaceous boundary in this region. High-browsing titanosauriform sauropods had small overlap in the trophic niche with the ornithopods, facilitating a sympatric coexistence of both groups. However, their range was dependent on high-canopy vegetation that was probably more abundant in uplands. The previously observed "mid-Cretaceous bottleneck" in sauropod diversity may therefore be a result of partial extinction and/or a sampling bias, as the preservation of upland faunas are very exceptional. However, it is be cautioned to interpolate these regional observations to global sauropod diversity patterns.
... ISSN 0001-6594 record of plants in the Morrison Formation is also extensive based on macrofossils (Tidwell and Rushforth, 1970;Medlyn and Tidwell, 1975a, b;1979;Tidwell, 1990aTidwell, , b, 1994Ash, 1990, 2006;Medlyn, 1992, 1993;Ash, 1994;Ash and Tidwell, 1998;Tidwell et al., 1998;Gee and Tidwell, 2010;Gee, 2011Gee, , 2013Gee, , 2016Gee et al., 2014Gee et al., , 2019 as well as pollen and spores (Litwin et al., 1998;Baghai-Riding, 2010, 2016), but so far the generally poor preservation of the plant megafossil, and the uncertain affinities of dispersed palynomorphs has hindered their contribution to understanding the structure and evolutionary biology of Jurassic plants. ...
Three dimensional calcitic casts of a two-seeded compound cone are described from the Upper Jurassic Brushy Basin Member of the Morrison Formation based on specimens from Colorado and Utah. Cones of Bassitheca hoodiorum gen. et sp. nov. are broadly obovate in face view, ~3.5 mm high, ~2.6 mm wide, and viewed from above have two planes of symmetry. Micro-CT scanning of numerous specimens shows that each cone has two well-developed orthotropous seeds positioned opposite each other in the major plane and separated by a median longitudinal septum in the minor plane. At a higher level in the cone, a median apical septum in the major plane separates two depressions arranged opposite each other. The two well-developed seeds in the major plane are enclosed by bracts, but numerous incomplete cones, together with cones showing lines of dehiscence, indicate that each seed was shed by the abscission of a lateral valve. One specimen indicates that three vascular bundles entered the base of each well-developed seed and these are interpreted as the vascular supply to the envelope of a chlamydospermous ovule. The opposite and decussate arrangement of bracts at the base of the cone, the paired arrangement of the two well-developed seeds perpendicular to the two apical depressions, combined with the inferred seed envelope that was apparently shed with the seed, indicates a probable relationship to Gnetales and specifically to extant Ephedra . Along with Dayvaultia tetragona Manchester et Crane, also known from the Brushy Basin Member of the Morrison Formation, Bassitheca hoodiorum provides further evidence that the Gnetales were more significant in the Morrison vegetation than has been recognized previously.
... Firstly, there is wide variation in the digestibility and calorific content of the different plant groups available during the Mesozoic (e.g. 102,103 ), which might have led these taxa to select particular plant species or plant organs preferentially on the basis of their nutritional value. Secondly, due to its lower M b , M. vorosi should be expected to have higher mass-specific standard metabolic rates than the larger H. tormai (e.g., 104 ). ...
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Dentitions of the sympatric herbivorous dinosaurs Hungarosaurus (Ankylosauria, Nodosauridae) and Mochlodon (Ornithopoda, Rhabdodontidae) (Santonian, Hungary) were analysed to investigate their dietary ecology, using several complementary methods—orientation patch count, tooth replacement rate, macrowear, tooth wear rate, traditional microwear, and dental microwear texture analysis (DMTA). Tooth formation time is similar in Hungarosaurus and Mochlodon, and traditional and DMTA microwear features suggest low-browsing habits for both taxa, consistent with their inferred stances and body sizes. However, Mochlodon possesses a novel adaptation for increasing dental durability: the dentine on the working side of the crown is double the thickness of that on the balancing side. Moreover, crown morphology, enamel thickness, macrowear orientation, and wear rate differ greatly between the two taxa. Consequently, these sympatric herbivores probably exploited plants of different toughness, implying dietary selectivity and niche partitioning. Hungarosaurus is inferred to have eaten softer vegetation, whereas Mochlodon likely fed on tougher material. Compared to the much heavier, quadrupedal Hungarosaurus, the bipedal Mochlodon wore down more than twice as much of its crown volume during the functional life of the tooth. This heavy tooth wear might correlate with more intensive food processing and, in turn, could reflect differences in the metabolic requirements of these animals.
... The palaeobotany of the Morrison Formation has been studied less extensively and is less well known, but includes macrofossils of conifers, ginkgophytes, cycads, bennettitaleans and ferns (Tidwell & Rushforth 1970;Tidwell 1990aTidwell , b, 1994Tidwell & Ash 1990;Ash 1994;Tidwell et al. 1998;Gee & Tidwell 2010;Gee 2011Gee , 2016Gee et al. 2014), as well as abundant silicified wood (Medlyn & Tidwell 1975a, b, 1979Tidwell & Medlyn 1993;Gee et al. 2019). Palynological investigations also document the presence of diverse pteridophytes and gymnosperms (Hotton & Baghai-Riding 2010. ...
A new kind of seed-bearing structure is described based on three-dimensional casts and partially permineralized small cones from the Upper Jurassic Brushy Basin Member of the Morrison Formation, in the Henry Mountains of Utah. Cones of Dayvaultia tetragona gen. et sp. nov. are obovate in lateral view, 10.0–11.0 mm long, square in cross-section and 5.1–8.0 mm wide, with a thick wall composed of four tightly adhering bracts that open apically to expose the tips of six or eight elongate, four-lobed seeds. Micro-CT scanning reveals that the seeds are borne on a cup-shaped receptacle in a regular opposite and decussate manner. This regular arrangement, as well as similarities of the seeds to several kinds of Early Cretaceous chlamydospermous seeds, including those of Lobospermum and Battenispermum, suggests a relationship to extant and Cretaceous members of Gnetales. The sedimentary context in which the cones occur, combined with their local abundance, suggests that Dayvaultia was common on intermittently inundated well-drained floodplains during Morrison times, enhancing insight into the vegetation that supported the diverse vertebrate faunas for which the Morrison Formation is well known.
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The recent discovery of iguanodontid remains from the new Palau-3 site in the Lower Cretaceous Morella Formation is the most complete non-articulated skeleton of Iguanodon bernissartensis on the NE Iberian Peninsula. To elucidate the paleoenvironment of the Palau-3 site, a palynological analysis was carried out on matrix samples collected from around the skeleton. The palynological assemblage is found to correspond to an upper Barremian age. While the assemblage is composed of bryophytes, pteridophytes, gymnosperms, freshwater algae, dinoflagellate cysts and fungal spores, the palynoflora is mostly dominated by the Cheirolepidiaceae conifer (Classopollis) and Anemiaceae fern (mainly Cicatricosisporites) families. The absence of angiosperm pollen in this flora is also noteworthy, as angiosperm remains have been recorded previously elsewhere in the Morella Formation. At the Palau-3 site, the fronds of Cyatheaceae and Anemiaceae ferns, as well as the foliage of the Cheirolepidiaceae conifers, may have been the major sources of nutrition of I. bernissartensis and other herbivorous iguanodontians. The paleobotany of the four major localities bearing I. bernissartensis remains in western Europe was surveyed to determine the habitat and feeding preferences of this styracosternan dinosaur. These localities are Bernissart (Belgium), Isle of Wight (England), Nehden (Germany), and Morella (Spain). In accordance to this survey, the habitat preferences of I. bernissartensis and association with specific plant communities show that this ornithopod species was adapted to a wide variety of paleoenvironments.
This review study has focused on existing sedimentological information of Late Jurassic transgressive deposits of Tendaguru Formation (110 m thick), Mandawa basin, Tanzania exposed around Tendaguru hill and Kanthkot Formation (150 m thick), Kachchh basin, India exposed near Wagad hill. Based on comparison between the two coeval deposits shows variable transgressive characteristics. Studies have revealed that during transgression there existed a storm-dominated sedimentary facies in Kanthkot Formation and tidally influenced facies type in Tendaguru Formation. Both represent similar cyclic sedimentation patterns and high-energy transgressive deposits into different depositional regimes. Lithofacies review reveals that Kachchh basin (Wagad region) was an open marine and relatively deeper and steeper shelf environment in late Jurassic time. However, Mandawa basin (Tendaguru region) was a restricted marginal marine with an estuarine setting. Faunal affinities in both formations indicate a shallow marine environment of deposition with variable depth. The close similarity of transgressive episodes and upward stacking pattern of facies successions in both basins indicates overall shallowing of the sea that correlates with the global trend of relative sea-level fall during late Jurassic time.
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The Late Jurassic to Early Cretaceous Tendaguru Beds (Tanzania, East Africa) have been well known for nearly a century for their diverse dinosaur assemblages. Here, we present sedimentological and palaeontological data collected by the German-Tanzanian Tendaguru Expedition 2000 in an attempt to reconstruct the palaeo-ecosystems of the Tendaguru Beds at their type locality. Our reconstructions are based on sedimentological data and on a palaeoecological analysis of macroinvertebrates, microvertebrates, plant fossils and microfossils (ostracods, foraminifera, charophytes, palynomorphs). In addition, we included data from previous expeditions, particularly those on the dinosaur assemblages. The environmental model of the Tendaguru Beds presented herein comprises three broad palaeoenvironmental units in a marginal marine setting: (1) Lagoon-like, shallow marine environments above fair weather wave base and with evidence of tides and storms. These formed behind barriers such as ooid bar and siliciclastic sand bar complexes and were generally subject to minor salinity fluctuations. (2) Extended tidal flats and low-relief coastal plains. These include low-energy, brackish coastal lakes and ponds as well as pools and small fluvial channels of coastal plains in which the large dinosaurs were buried. Since these environments apparently were, at best, poorly vegetated, the main feeding grounds of giant sauropods must have been elsewhere. Presumably, tidal flats and coastal plains were visited by dinosaurs primarily during periods of drought. (3) Vegetated hinterland. Vegetation of this environment can only be inferred indirectly from plant material transported into the other depositional environments. Vegetation was dominated by a diverse conifer flora, which apparently formed part of the food source of large herbivorous sauropods. Evidence from various sources suggests a subtropical to tropical palaeoclimate, characterised by seasonal rainfall alternating with a pronounced dry season during the Late Jurassic. In Early Cretaceous times, sedimentological and palaeontological proxies suggest a climatic shift towards more humid conditions. Die Tendaguru-Schichten von Tansania in Ostafrika (Oberjura bis Unterkreide) sind als Lagerstätte oberjurassischer Dinosaurier seit nahezu einem Jahrhundert weltweit bekannt. Anhand von sedimentologischen und paläontologischen Daten, die während der Deutsch-Tansanischen Tendaguru Expedition 2000 im Typus-Gebiet der Tendaguru-Schichten gewonnen wurden, werden Paläo-Ökosysteme rekonstruiert. Grundlage der Rekonstruktionen sind die Auswertung sedimentologischer Daten sowie die paläo-ökologische Analyse von Makroinvertebraten, Mikrovertebraten, pflanzlichen Fossilien und Mikrofossilien (Ostrakoden, Foraminiferen, Charophyten, Palynomorphen). Darüber hinaus werden Informationen über Dinosaurier berücksichtigt, die bei früheren Expeditionen gewonnen wurden. Das hier vorgestellte Ablagerungsmodell der Tendaguru-Schichten umfaßt drei Teilbereiche eines randlich marinen Sedimentationsraumes, die wie folgt gekennzeichnet werden können: (1) Lagunen-artige, marine Flachwasserbereiche, die oberhalb der Schönwetter-Wellenbasis lagen und unter deutlichem Einfluß von Gezeiten und Stürmen standen. Sie waren vom offenen Meer durch Barrieren, wie Ooidbarren und siliziklastischen Sandbarrenkomplexen, getrennt und wiesen einen leicht schwankenden Salzgehalt auf. (2) Ausgedehnte Wattgebiete und flache Küstenebenen. Dort befanden sich niedrig-energetische, brackische Strandseen und Teiche sowie Tümpel und kleinere Flußrinnen, in denen die großen Dinosaurier eingebettet wurden. Da diese Lebensräume bestenfalls dürftig bewachsen waren, müssen die Nahrungsquellen und der eigentliche Lebensraum der riesigen Sauropoden anderswo gelegen haben. Vermutlich wurden die Wattgebiete und Flachküsten von Dinosauriern vorrangig in den Trockenzeiten aufgesucht. (3) Bewachsenes Hinterland. Die Vegetation dieses Lebensraumes kann nur indirekt aus Pflanzenresten erschlossen werden, die in die anderen Ablagerungsraume transportiert wurden. Die Vegetation wurde von einer diversen Koniferenflora dominiert, die zumindest teilweise die Nahrungsgrundlage der großen, herbivoren Sauropoden bildete. Sedimentologische und paläontologische Indikatoren sprechen für ein subtropisches bis tropisches Klima wahrend der späten Jurazeit mit einem jahreszeitlichen Wechsel von Regenfällen und ausgeprägten Trockenzeiten. In der frühen Kreidezeit deutet sich ein Wechsel zu starker humiden Bedingungen an. doi:10.1002/mmng.20020050103
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Some dinosaurs, notably the sauropods, were the largest of all land animals, present or past. There is no generally agreed reason for this gigantism. We question the recent suggestion that this was due to high productivity, from high CO2 concentrations, at the time of the dinosaurs. Instead, we suggest the reason for this large size was because typical Jurassic/Triassic plants, such as cycads and conifers, were of inherently low food quality (low nitrogen concentration). High CO2 at the time of the dinosaurs would have resulted in an even lower food quality. Present-day megaherbivores are associated with relatively low-quality food-plants and we suggest this applied to sauropods.
Marattia aganzhenensis sp. nov. from the Lower Jurassic Daxigou Formation of Lanzhou, Gansu, China, is the second species of Marattia known in fertile structure from China, in addition to Marattia asiatica. The new species demonstrates the variability of the genus through its distinct character states. This new species is distinguished by the absence of venuli recurrentes, the shorter synangia, exclusively monolete spores without surface ornamen- tation, and the low number of spores produced per sporangium. Keywords: China, Gansu, Lower Jurassic, Marattia aganzhenensis sp. nov., Marattiales.
The Tendaguru Beds, southeastern Tanzania, have yielded two palynological assemblages of Kimmeridgian to Tithonian age: (1) the Anapiculatisporites-Densoisporites-Trisaccites assemblage from the Middle Saurian Beds and (2) the Barbatacysta-Pareodinia assemblage from the overlying Smeei Beds. A third assemblage with Rhizophagites and rare angiosperm pollen from the Upper Saurian Beds is contaminated by recent and subrecent material. The Anapiculatisporites-Densoisporites-Trisaccites assemblage is characterized by the presence of freshwater algae (Ovoidites), pteridopyhtic-bryophytic spores and gymnosperm (conifer) pollen, with Classopollis as the most abundant element. Among the rare elements of this assemblage is the questionable dinoflagellate Mendicodinium? quadratum, possibly a Kimmeridgian-Tithonian marker. The miospores show palaeobiogeographic links to Southern Gondwana, especially Madagascar, Australia, Argentina and India. Deposition of this assemblage took place in an aquatic environment with strong palynological influx from a terrestrial source and questionable marine influence. The Barbatacysta-Pareodinia assemblage contains a considerable number of dinoflagellates suggesting deposition in a marine environment. The terrestrially-derived miospores are impoverished and dominated by conifer pollen, while pteridophytic-bryophytic spores form a very subordinate element or are absent. Die Tendaguru-Schichten, Südost-Tansania, haben zwei palynologische Assoziationen, deren Alter als Kimmeridge bis Tithon interpretiert wird, geliefert. Die Anapiculatisporites-Densoisporites-Trisaccites-Assoziation stammt aus den Mittleren Saurierschichten, und die Barbatacysta-Pareodinia-Assoziation charakterisiert die darüberlagernden Smeei-Schichten. Eine dritte Vergesellschaftung mit Rhizophagites und seltenen Angiospermen-Pollen aus den Oberen Saurierschichten ist durch rezentes bis subrezentes Material kontaminiert. Die Anapiculatisporites-Densoisporites-Trisaccites-Assoziation ist durch die Anwesenheit von Süßwasser-Algen (Ovoidites), Pteridophyten-Bryophyten-Sporen und Gymnospermen-Pollen (Koniferen) gekennzeichnet mit Classopollis als dem häufigsten Element. Zu den seltenen Elementen dieser Assoziation gehört der fragliche Dinoflagellat Mendicodinium? quadratum, der möglicherweise als leitend für das Kimmeridge-Tithon angesehen werden kann. Die Miosporen zeigen paläobiogeographische Verbindungen nach Südgondwana, besonders nach Madagaskar, Australien, Argentinien und Indien. Das Ablagerungsmilieu dieser Assoziation war aquatisch mit starker Zufuhr von terrigenem Material, während mariner Einfluß fraglich ist. Die Dinoflagellaten-führende Barbatacysta-Pareodinia-Assoziation wurde in einem marinen Milieu gebildet, in dem die Zufuhr terrigener Palynomorphe reduziert und im wesentlichen auf Koniferen-Pollen beschränkt war, während Pteridophyten-Bryophyten-Sporen nur sehr untergeordnet vorkommen oder ganz fehlen. doi:10.1002/mmng.1999.4860020113
The primary productivity of the world is of paramount importance for man. Primary productivity captures that portion of solar energy that supports the life of all components of the biosphere. The largest portion of human food is provided by the productivity of plant life on land. From land production also comes our greatest single substance for construction and fabrication—wood—and a host of other products. The productivity of vegetation is one major aspect (the accumulation of toxic materials in the environment and potential psychologic effects are others) of the carrying capacity of the earth for man—its ability to support human populations on a long-term basis. Fossil fuels are accumulated profits from past primary production. The mantle of vegetation protects the Earth’s surface against destructive erosion; and it provides an important part of the environmental context in which man and his societies have developed and in which man himself feels most at home. It is by primary productivity and the growth of plants by the creation of organic matter through photosynthesis that the life of the vegetational mantle and thereby of man is maintained.