ArticlePDF Available

Behavior of hadrosaurs as interpreted from footprints in the "Mesaverde" Group (Campanian) of Colorado, Utah, and Wyoming

Authors:
A preview of the PDF is not available
... Tracks have the additional capacity to reveal possible morphological changes (particularly of soft tissue) and gait changes associated with growth, although unequivocal referral of different sized or shaped prints to a single taxon (or ichnotaxon) is difficult (Hornung et al., 2016). Among dinosaurs, possible ontogenetic changes have been proposed on the basis of ichnology for some non-avian theropods (Olsen, 1980;Olsen et al., 1998;Clark et al., 2005;Pascual-Arribas and Hernández-Medrano, 2011), ornithopods (Currie and Sarjeant, 1979;Carpenter, 1992;Lockley, 1994;Matsukawa et al., 1999;Hornung et al., 2016), and a nodosaurid (McCrea et al., 2014a:fig. 68). ...
... To date, tracks attributed to tyrannosaurids have been reported from Canada, the U.S.A., Mexico, China and Mongolia (e.g., Lockley, 1988;Carpenter, 1992;Currie et al., 2003;Manning et al., 2008;Ishigaki et al., 2009;Lockley et al., 2011a;McCrea et al., 2005McCrea et al., , 2014aMcCrea et al., , 2014bSmith et al., 2016;Rivera-Sylva et al., 2017;Nakajima et al., 2018;Xing et al., 2019; see Supplementary Material for a review). Most of these tracks exceed 45 cm in length and were presumably produced by subadult or adult animals based on their large size. ...
... In order to explore whether the results of our Wapiti Formation dataset reflect broader patterns within tyrannosaurids, a further eight tracks attributed to tyrannosaurids from other geological contexts were selected from the literature and incorporated into a second (global) geometric morphometric analysis (Fig. S1). These include tracks from Lockley (1988), Carpenter (1992, fig. 2), the figured outline shows wider digital impressions and more anterior hypices than what we interpret from the provided photographs. ...
Article
Fossil tracks should theoretically capture differences in pedal anatomy between growth stages of the same taxon, particularly those related to the soft tissue of the foot, providing a more realistic view of pedal ontogeny than skeletal material alone. However, recognizing these ontogenetic trajectories is complicated by the influence of preservation and kinematics on track morphology, as well as the inherent difficulty of referring different tracks to a single taxon. Here, we explore differences in track morphology from a collection of tracks attributed to tyrannosaurids from Unit 4 of the Wapiti Formation (upper Campanian) in western Canada. Along with morphology, close geographic and stratigraphic associations suggest that the tracks pertain to similar tyrannosaurid trackmakers. A geometric morphometric analysis of the track outlines reveals size-dependent increase in relative track robusticity, driven primarily by an increase in 'heel' breadth and surface area. This relationship is lost when the dataset is expanded to include tyrannosaurid tracks globally, which we attribute to increased stratigraphic and taxonomic 'noise' within the global dataset that masks the tightly constrained patterns obtained from the Wapiti Formation tracks. Although there is some substrate and kinematic influence on certain aspects of track morphology, we hypothesize that the observed size-dependent relationship reflects genuine expansion in the breadth of the heel soft tissues and probably their overall surface area associated with growth. Increased pedal robusticity likely assisted with weight bearing and locomotor stability as body mass increased over ontogeny, supporting previous hypotheses that some tyrannosaurids underwent a growth-related reduction in relative agility and/or cursorial performance.
... A variety of tetrapod tracks are known from the Blackhawk Formation and a number of other rock units that make up the larger stratigraphic unit known as the "Mesaverde" Group sensu lato (Carpenter, 1992). The Mesaverde Group is well known as a coal-bearing sequence, interpreted as part of a wave-dominated delta system along the coastal plain of the Cretaceous Western Interior Seaway. ...
... Because most of these were never studied in context, much of the early 20 th century literature was anecdotal and of limited scientific interest (Peterson, 1924;Strevell, 1932;Brown, 1938;Look, 1951Look, , 1955Bird 1985). It has only been since the 1980s that descriptions of tetrapod tracks from the Mesaverde Group have appeared in the scientific literature (Lockley et al., 1983(Lockley et al., , 20112018a;Balsley, 1986, 1989;Parker and Rowley, 1989;Robison, 1991;Lockley, 1999;Carpenter, 1992;Lockley and Foster, 1993). These reports have dealt mostly with dinosaur tracks, identified only generally as hadrosaurian, theropodan or ceratopsian (e.g., Parker and Balsley, 1989;Carpenter, 1992;Lockley and Hunt, 1995a). ...
... It has only been since the 1980s that descriptions of tetrapod tracks from the Mesaverde Group have appeared in the scientific literature (Lockley et al., 1983(Lockley et al., , 20112018a;Balsley, 1986, 1989;Parker and Rowley, 1989;Robison, 1991;Lockley, 1999;Carpenter, 1992;Lockley and Foster, 1993). These reports have dealt mostly with dinosaur tracks, identified only generally as hadrosaurian, theropodan or ceratopsian (e.g., Parker and Balsley, 1989;Carpenter, 1992;Lockley and Hunt, 1995a). Non-dinosaurian tracks have been placed in unnamed categories, such as bird and frog (Robison, 1991). ...
Article
The only described Cretaceous frog tracksite known from North America, from outcrops of the Blackhawk Formation in Meetinghouse Canyon, Utah, had previously, additionally yielded only a small number relatively large, unnamed tetradactyl avian theropod (bird) tracks. Unnamed avian dinosaur (bird) and non-avian dinosaur tracks had also been reported from the nearby locality of Straight Canyon. These two localities were revisited with the aim of collecting additional material, with the result that a third site was discovered. Collectively, tracks of avian and non-dinosaurs, pterosaurs, crocodylians and turtles were discovered, together with invertebrate traces. These include representatives of the following ichnogenera (with inferred trackmaker in parentheses): grallatorid similar to Kalohipus (non-avian theropod), Saurexallopus (?avian or non-avian theropod), Hadrosauropodus isp. (hadrosaur), Ceratopsipes isp. (ceratopsian), Pteraichnis isp., (pterosaur), Mehliella and Hatcherichus (crocodylian), Chelonipus (turtle) and Ranipes (frog). This tetrapod ichnodiversity of nine ichnogenera is one of the highest known for any Cretaceous formation.
... A variety of tetrapod tracks are known from the Blackhawk Formation and a number of other rock units that make up the larger stratigraphic unit known as the "Mesaverde" Group sensu lato (Carpenter, 1992). The Mesaverde Group is well known as a coal-bearing sequence, interpreted as part of a wave-dominated delta system along the coastal plain of the Cretaceous Western Interior Seaway. ...
... Because most of these were never studied in context, much of the early 20 th century literature was anecdotal and of limited scientific interest (Peterson, 1924;Strevell, 1932;Brown, 1938;Look, 1951Look, , 1955Bird 1985). It has only been since the 1980s that descriptions of tetrapod tracks from the Mesaverde Group have appeared in the scientific literature (Lockley et al., 1983(Lockley et al., , 20112018a;Balsley, 1986, 1989;Parker and Rowley, 1989;Robison, 1991;Lockley, 1999;Carpenter, 1992;Lockley and Foster, 1993). These reports have dealt mostly with dinosaur tracks, identified only generally as hadrosaurian, theropodan or ceratopsian (e.g., Parker and Balsley, 1989;Carpenter, 1992;Lockley and Hunt, 1995a). ...
... It has only been since the 1980s that descriptions of tetrapod tracks from the Mesaverde Group have appeared in the scientific literature (Lockley et al., 1983(Lockley et al., , 20112018a;Balsley, 1986, 1989;Parker and Rowley, 1989;Robison, 1991;Lockley, 1999;Carpenter, 1992;Lockley and Foster, 1993). These reports have dealt mostly with dinosaur tracks, identified only generally as hadrosaurian, theropodan or ceratopsian (e.g., Parker and Balsley, 1989;Carpenter, 1992;Lockley and Hunt, 1995a). Non-dinosaurian tracks have been placed in unnamed categories, such as bird and frog (Robison, 1991). ...
... Since the 1920s Upper Cretaceous tetrapod tracks have been reported from the coal-bearing strata of the broadly defined Mesaverde Group (Campanian and Maastrichtian) at various sites in Utah, Colorado, and Wyoming, especially around the Price coal mining district of Utah and Grand Mesa in western Colorado (Carpenter, 1992). During the deposition of this unit, swamps were developing in interdeltaic to coastal plain environments (Parker and Balsley, 1989;Carpenter, 1992). ...
... Since the 1920s Upper Cretaceous tetrapod tracks have been reported from the coal-bearing strata of the broadly defined Mesaverde Group (Campanian and Maastrichtian) at various sites in Utah, Colorado, and Wyoming, especially around the Price coal mining district of Utah and Grand Mesa in western Colorado (Carpenter, 1992). During the deposition of this unit, swamps were developing in interdeltaic to coastal plain environments (Parker and Balsley, 1989;Carpenter, 1992). Some tracks have been extracted as isolated casts from the roofs of coal mines (Peterson, 1924) whereas others have been described from surface exposures (Robison, 1991;Lockley and others, 2011). ...
... In the 1930s the tracks were often treated sensationally, as in the case of Peterson's claim of a Tyrannosaurus track and Barnum Brown's excavation of a slab for the American Museum with tracks he attributed to a "mystery dinosaur" with a giant stride (Brown, 1938). These latter interpretations figured in 1970s debates about dinosaur speed, as well as by Carpenter (1992). Only in a few cases have large surfaces with trackway segments been mapped in detail others, 1983, 2011;Parker and Balsley, 1989). ...
Article
Full-text available
Although only recognized as a discrete stratigraphic unit since 1944, the Cedar Mountain Formation represents tens of millions of years of geological and biological history on the central Colorado Plateau. This field guide represents an attempt to pull together the results of recent research on the lithostratigraphy, chronostratigraphy, sequence stratigraphy, chemostratigraphy, and biostratigraphy of these medial Mesozoic strata that document the dynamic and complex geological history of this region. Additionally, these data provide a framework by which to examine the history of terrestrial faunas during the final breakup of Pangaea. In fact, the medial Mesozoic faunal record of eastern Utah should be considered a keystone in understanding the history of life across the northern hemisphere. Following a period of erosion and sediment bypass spanning the Jurassic–Cretaceous boundary, sedimentation across the quiescent Colorado Plateau began during the Early Cretaceous. Thickening of these basal Cretaceous strata across the northern Paradox Basin indicate that salt tectonics may have been the predominant control on deposition in this region leading to the local preservation of fossiliferous strata, while sediment bypass continued elsewhere. Thickening of overlying Aptian strata west across the San Rafael Swell provides direct evidence of the earliest development of a foreland basin with Sevier thrusting that postdates geochemical evidence for the initial development of a rain shadow.
... Since the 1920s Upper Cretaceous tetrapod tracks have been reported from the coal-bearing strata of the broadly defined Mesaverde Group (Campanian and Maastrichtian) at various sites in Utah, Colorado, and Wyoming, especially around the Price coal mining district of Utah and Grand Mesa in western Colorado (Carpenter, 1992). During the deposition of this unit, swamps were developing in interdeltaic to coastal plain environments (Parker and Balsley, 1989;Carpenter, 1992). ...
... Since the 1920s Upper Cretaceous tetrapod tracks have been reported from the coal-bearing strata of the broadly defined Mesaverde Group (Campanian and Maastrichtian) at various sites in Utah, Colorado, and Wyoming, especially around the Price coal mining district of Utah and Grand Mesa in western Colorado (Carpenter, 1992). During the deposition of this unit, swamps were developing in interdeltaic to coastal plain environments (Parker and Balsley, 1989;Carpenter, 1992). Some tracks have been extracted as isolated casts from the roofs of coal mines (Peterson, 1924) whereas others have been described from surface exposures (Robison, 1991;Lockley and others, 2011). ...
... In the 1930s the tracks were often treated sensationally, as in the case of Peterson's claim of a Tyrannosaurus track and Barnum Brown's excavation of a slab for the American Museum with tracks he attributed to a "mystery dinosaur" with a giant stride (Brown, 1938). These latter interpretations figured in 1970s debates about dinosaur speed, as well as by Carpenter (1992). Only in a few cases have large surfaces with trackway segments been mapped in detail others, 1983, 2011;Parker and Balsley, 1989). ...
Article
Full-text available
Although only recognized as a discrete stratigraphic unit since 1944, the Cedar Mountain Formation represents tens of millions of years of geological and biological history on the central Colorado Plateau. This field guide represents an attempt to pull together the results of recent research on the lithostratigraphy, chronostratigraphy, sequence stratigraphy, chemostratigraphy, and biostratigraphy of these medial Mesozoic strata that document the dynamic and complex geological history of this region. Additionally, these data provide a framework by which to examine the history of terrestrial faunas during the final breakup of Pangaea. In fact, the medial Mesozoic faunal record of eastern Utah should be considered a keystone in understanding the history of life across the northern hemisphere. Following a period of erosion and sediment bypass spanning the Jurassic–Cretaceous boundary, sedimentation across the quiescent Colorado Plateau began during the Early Cretaceous. Thickening of these basal Cretaceous strata across the northern Paradox Basin indicate that salt tectonics may have been the predominant control on deposition in this region leading to the local preservation of fossiliferous strata, while sediment bypass continued elsewhere. Thickening of overlying Aptian strata west across the San Rafael Swell provides direct evidence of the earliest development of a foreland basin with Sevier thrusting that postdates geochemical evidence for the initial development of a rain shadow.
... Hadrosaurids-Closely associated and aligned large ornithopod trackways are a long-documented phenomenon known from Cretaceous tracksites around the world (e.g., [2,3,77,[111][112][113][114][115]). Skeletal and other evidence, including rare nesting sites (e.g., [116][117][118]) and common hadrosaurid-dominated bonebeds (e.g., [20,25,[119][120][121][122][123]) further indicate widespread herding behaviour among these dinosaurs. ...
... Alaskan ichnoassemblages within the Chignik and lower Cantwell formations are most often dominated by Hadrosauropodus, although the latter unit is probably early Maastrichtian in age [29,31,32]. Similarly, late Campanian track horizons within the Oldman, Dinosaur Park, Horseshoe Canyon, and St. Mary River formations of southern Alberta, as well as the 'Mesaverde Group' of Utah, Wyoming, Colorado, and the Fruitland Formation of New Mexico, are all hadrosaurid-dominated [3,43,60,75,87,[145][146][147][148][149][150][151][152][153] and references therein] (Fig 16). In Mexico, ichnofaunas of the Cerro del Pueblo Formation are hadrosaurid-dominated in terms of footprint abundance, although theropod tracks occur at a larger number of tracksites [139,[154][155][156]. ...
Article
Full-text available
The Wapiti Formation of northwest Alberta and northeast British Columbia, Canada, preserves an Upper Cretaceous terrestrial vertebrate fauna that is latitudinally situated between those documented further north in Alaska and those from southern Alberta and the contiguous U.S.A. Therefore, the Wapiti Formation is important for identifying broad patterns in vertebrate ecology, diversity, and distribution across Laramidia during the latest Cretaceous. Tracksites are especially useful as they provide a range of palaeoecological, palaeoenvironmental, and behavioural data that are complementary to the skeletal record. Here, we describe the Tyrants Aisle locality, the largest in-situ tracksite known from the Wapiti Formation. The site occurs in the lower part of Unit 4 of the formation (~72.5 Ma, upper Campanian), exposed along the southern bank of the Redwillow River. More than 100 tracks are documented across at least three distinct track-bearing layers, which were deposited on an alluvial floodplain. Hadrosaurid tracks are most abundant, and are referable to Hadrosauropodus based on track width exceeding track length, broad digits, and rounded or bilobed heel margins. We suggest the hadrosaurid trackmaker was Edmontosaurus regalis based on stratigraphic context. Tyrannosaurids, probable troodontids, possible ornithomimids, and possible azhdarchid pterosaurs represent minor but notable elements of the ichnofauna, as the latter is unknown from skeletal remains within the Wapiti Formation, and all others are poorly represented. Possible social behaviour is inferred for some of the hadrosaurid and small theropod-like trackmakers based on trackway alignment, suitable spacing and consistent preservation. On a broad taxonomic level (i.e., family or above), ichnofaunal compositions indicate that hadrosaurids were palaeoecologically dominant across Laramidia during the late Campanian within both high-and low-latitude deposits, although the role of depositional environment requires further testing.
... The possible gregarious behavior of dinosaurs has been reported many times, such as multiple (sub-) parallel trackways, the congregation of eggs and nests, or the concentration of skeletons of a single or similar species (Ostrom, 1972;Horner and Makela, 1979;Currie, 1998;Kobayashi and Lü, 2003). Although there are many reports on multiple parallel ornithopod trackways in the world, most of them were imprinted by only adults or a mixed group of adults and juveniles (Carpenter, 1992;Matsukawa et al., 2001;Zhang et al., 2006;Xing et al., 2007Xing et al., , 2015Kim et al., 2009;Lockley et al., 2012c;Fiorillo et al., 2014;Piñuela et al., 2016). Although evidence of the juvenile communities had been reported among various dinosaur taxa such as ornithomimids, sauropods, and ceratopsians based on their body fossils (Varricchio et al., 2008;Myers and Fiorillo, 2009;Zhao et al., 2013), the ichnological evidence for proving is relatively rare in ornithopod dinosaurs. ...
Article
Full-text available
A new dinosaur tracksite with footprints of non-adult ornithopods was discovered from the Lower Cretaceous Haman Formation (Albian), Gunbuk District, Haman County, South Gyeongsang Province of South Korea in 2018. The tracksite consists of 58 ornithopod footprints (seven short trackways and 26 isolated footprints) within three track-bearing horizons partially exposed on the small creek bottom. Lithofacies and sedimentary structures of the track-bearing horizons and overlying strata suggest a marginal lacustrine environment. All tracks are sub-symmetrical tridactyl and small-to medium-sized pes prints. They have wide, blunt, short digital impressions with a large, rounded heel pad impression. No manus print is observable in the tracksite. Tracks are generally longer than their width with a distinctly developed digit III. Trackways show the inward (negative) rotation of footprints. The morphological characteristics of the footprints are most likely attributable to ichnogenus Caririchnium. A relatively small pes size (lengths range from 13 to 27 cm) indicates that the trackmakers were juvenile to subadult ornithopods when compared with the contemporary large ornithopods in South Korea. The majority of the trackways show preferred orientations with trends of parallel to subparallel groupings on each surface, suggesting gregarious behavior. Notably, the tracksite consists exclusively of juvenile ornithopod dinosaurs, which is an uncommon phenomenon when compared to other ornithopod tracksites with age-mixed or large ornithopod footprints reported from other localities around the world. The absence of the adult ornithopod tracks may be interpreted as the spatial segregation of an ornithopod population based on their ages and the formation of juvenile-only communities without parental care.
... The only other Mesozoic frog tracks occurrence (Robison, 1991) currently described comes from the Upper Cretaceous Blackhawk Formation of Utah (Parker and Balsley, 1989;Carpenter, 1992), which is dated as Campanian (~83e70 Ma). As noted above the Jinju Formation is considered late Aptian to early Albian in age according to Kang and Paik (2013): i.e. about 112 Ma. ...
Article
Newly discovered frog tracks from the Lower Cretaceous (upper Aptian–lower Albian) Jinju Formation, South Korea, represent only the second report from Asia, and only the third global report from the Mesozoic. They are also the oldest reported from the fossil record, and can be assigned to Ranipes isp. indet. These tracks add to the rapidly growing list of small tetrapod tracks recovered from large excavations in the Jinju Formation, in Jinju City. Such small tracks owe their preservation to an abundance of fine-grained lacustrine sediments suitable for registration of small tetrapod tracks that are generally very rare or absent from most facies. The trackways indicate hopping locomotion.
Article
Full-text available
The dinosaur track record features numerous examples of trackways with elongated metatarsal marks. Such ‘elongate tracks’ are often highly variable and characterized by indistinct outlines and abbreviated or missing digit impressions. Elongate dinosaur tracks are well-known from the Paluxy River bed of Texas, where some have been interpreted as ‘man tracks’ by creationists due to their superficially human-like appearance. The horizontal orientation of the metatarsal marks led to the now widely accepted idea of a facultative plantigrade, or ‘flat-footed’, mode of locomotion in a variety of dinosaurian trackmakers small to large. This hypothesis, however, is at odds with the observation that elongate tracks do not indicate reduced locomotion speeds and increased pace angulation values, but instead are correlated with low anatomical fidelity. We here interpret elongate tracks as deep penetrations of the foot in soft sediment. Sediment may collapse above parts of the descending foot, leaving a shallow surface track that preserves a metatarsal mark. The length of a metatarsal mark is determined by multiple factors and is not necessarily correlated with the length of the metatarsus. Other types of posterior marks in dinosaur footprints, such as drag and slip marks, are reviewed.
Article
The Los Menucos locality in Patagonia, Argentina, bears a well-known ichnofauna mostly documented by small therapsid footprints. Within this ichnofauna, large pentadactyl footprints are also represented but to date were relatively underinvestigated. These footprints are here analyzed and discussed based on palaeobiological indications (i.e., trackmaker identification). High resolution digital photogrammetry method was performed to achieve a more objective representation of footprint three-dimensional morphologies. The footprints under study are compared with Pentasauropus from the Upper Triassic lower Elliot Formation (Stormberg Group) of the Karoo Basin (Lesotho, southern Africa). Some track features suggest a therapsid-grade synapsid as the potential trackmaker, to be sought among anomodont dicynodonts (probably Kannemeyeriiformes). While the interpretation of limb posture in the producer of Pentasauropus tracks from the Los Menucos locality agrees with those described from the dicynodont body fossil record, the autopodial posture does not completely agree. The relative distance between the impression of the digital (ungual) bases and the distal edge of the pad trace characterizing the studied tracks likely indicates a subunguligrade foot posture (i.e., standing on the last and penultimate phalanges) in static stance, but plantiportal (i.e., the whole foot skeleton and related soft tissues are weight-bearing) during the dynamics of locomotion. The reconstructed posture might have implied an arched configuration of the articulated metapodials and at least of the proximal phalanges, as well as little movement capabilities of the metapodials. Usually, a subunguligrade-plantiportal autopod has been described for gigantic animals (over six hundreds kilograms of body weight) to obtain an efficient management of body weight. Nevertheless, this kind of autopod is described here for large but not gigantic animals, as the putative trackmakers of Pentasauropus were. This attribution implies that such an autopodial structure was promoted independently from the body size in the putative trackmakers. From an evolutionary point of view, subunguligrade-plantiportal autopods not necessarily must be related with an increase in body size, but rather the increase in body size requires a subunguligrade or unguligrade, plantiportal foot. Chronostratigraphically, Pentasauropus was reported from Upper Triassic deposits of South Africa and United States, and from late Middle Triassic and Upper Triassic deposits of Argentina. Based on the stratigraphic distribution of the ichnogenus currently accepted, a Late Triassic age is here proposed for the Pentasauropus -bearing levels of the Los Menucos Group.