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Publications (252)
The reorientation of Earth through rotation of its solid shell relative to its spin axis is known as True polar wander (TPW). It is well-documented at present, but the occurrence of TPW in the geologic past remains controversial. This is especially so for Late Jurassic TPW, where the veracity and dynamics of a particularly large shift remain debate...
Sedimentary deposits along convergent margins contain a record of sediment transfer and coupled tectonic processes. Deciphering the evolution of ancient convergent margins, both spatially and temporally, is challenging as their stratigraphic successions are often locally deformed, which makes it difficult to correlate stratigraphic units over large...
Cephalopods are among many marine animals that through some combination of habit and/or habitat have proven difficult to study, especially understanding their trophic positions in marine communities. Stable isotope analyses have provided powerful tools for discovering quantitative aspects about the ecology and food sources of many cephalopod specie...
Nautiloids are a charismatic group of marine molluscs best known for their rich fossil record, but today they are restricted to a handful of species in the family Nautilidae from around the Coral Triangle. Recent genetic work has shown a disconnect between traditional species, originally defined on shell characters, but now with new findings from g...
The latest Permian mass extinction (LPME) was triggered bymagmatism of the
Siberian Traps Large Igneous Province (STLIP), which left an extensive record
of sedimentary Hg anomalies at Northern Hemisphere and tropical sites. Here,
we present Hg records from terrestrial sites in southern Pangea, nearly antipodal
to contemporaneous STLIP activity, pro...
New collecting of ammonites and inoceramid bivalves from Cretaceous-Tertiary boundary sections exposed al Sopelana and Zumaya, Spain, and Hendaye and Bidart (Biarritz), France, has led to better understanding of molluscan biostratigraphy in each of these coastal exposures. Ali of these sections can be lithologically correlated. At all of the sectio...
Nautilus fisheries throughout the Philippines supported a worldwide trade in the nautilus shell for decades, with little to no management. A consequence has been significant declines in catch rate and low population abundances. This survey took place in April 2014 at Siquijor Island (9°17′30.7″N 123°38′36.5″E) and Dalaguete–Alcoy (09°43′20.9″N, 123...
The phragmocone-bearing coleoid cephalopods Sepia, Sepiella, Metasepia and Hemisepius (sepiids) are the most diverse of all extant chambered cephalopods and show the highest disparity. As such, they have a great potential to serve as model organisms to better understand the paleobiology not only of extinct coleoids, but of extinct nautiloids
and a...
Species of extant nautiluses (in Nautilus and Allonautilus) have been anecdotally described as opportunistic scavengers. Here, we examine foraging and scavenging behaviors of Nautilus in field and laboratory settings. Given that nautiluses are nektobenthic, solitary animals living in resource-limited habitats, we predict that odor is the predominan...
High Spatial-resolution Assessment of Diagenesis and Primary Isotopic Variability in Maastrichtian Molluscan Carbonates from Antarctica - Benjamin Linzmeier, Thomas Tobin, Peter Ward, Ian Orland, Daniella Assing, Kouki Kitajima, Phillip Gopon, Brian Huber, Shanan Peters, John Valley
The nautiloid lineage extends back nearly 500 million years but today, is represented by only two living genera, Nautilus and Allonautilus. Behavioral observations of these living nautiluses have improved our understanding of how nautiloids, and ammonoids, behaved and interacted in their environment. These behaviors may also help to inform conserva...
Key Point
Errors in stratigraphic age assignment of Cretaceous detrital zircon samples result in incorrect understanding of ages of geologic units
Cambridge Core - Computational Science and Modelling - Planets and Life - edited by Woodruff T. Sullivan, III
Living fossils are survivors of previously more diverse lineages that originated millions of years ago and persisted with little morphological change. Therefore, living fossils are model organisms to study both long-term and ongoing adaptation and speciation processes. However, many aspects of living fossils evolution and their persistence in the m...
Averaged demographic data from previously unfished populations of Nautilus and Allonautilus (Cephalopoda) provide a baseline to determine if a population is undisturbed and in “equilibrium” or is in “disequilibrium” as a result of fishery pressure. Data are available for previously undisturbed local nautiloid populations in Papua New Guinea, Austra...
Studying the paleoecology of the extinct chambered cephalopods is somewhat analogous to studying a distant landscape through the wrong end of a powerful telescope: we can see very small views of what must have been great panoramic vistas. Two factors have lead to this situation. First, the extant cephalopods still utilizing the phragmocone system o...
The role of the BDJ is to inform its readers of ideas, opinions, developments and key issues in dentistry - clinical, practical and scientific - stimulating interest, debate and discussion amongst dentists of all disciplines.
Figure S1. Bayesian inference tree of COI sequences of Nautilus pompilius sequences from our study and sequences of all nonredundant Nautilus spp. sequences from GenBank (in bold); GenBank entries that had identical DNA sequences from the same collection location were not included in the analysis.
Figure S2. Bayesian inference tree of 16S sequences of Nautilus pompilius from our study and sequences of N. macromphalus and Allonautilus scrobiculatus from GenBank.
Table S1. Descriptions and defining characters of Nautilus species examined in this study.
Table S3. AMOVA of all Nautilus spp. COI sequences from GenBank.
Table S2. Information for GenBank sequences from previous studies used in phylogenetic analysis including species identifications from previous studies, collection sites (country and specific location), Genbank accessions for COI or 16S, and the publication or study that submitted the sequence.
Table S4. Population average pairwise differences for samples from this study, using concatenated 16S‐COI sequences.
Figure S3. Median‐joining network of COI haplotypes for Nautilus sp. from GenBank with 95% confidence.
The cephalopod genus Nautilus is considered a "living fossil" with a contested number of extant and extinct species, and a benthic lifestyle that limits movement of animals between isolated seamounts and landmasses in the Indo-Pacific. Nautiluses are fished for their shells, most heavily in the Philippines, and these fisheries have little monitorin...
Recent work suggests that the Chicxulub bolide impact was not the only significant mechanism driving the Cretaceous-Paleogene (K/Pg) mass extinction event (~65.5 Ma) and that there must have been several other mechanisms including climate change which also contributed to this event. The sequence, nature and magnitude of climate change approaching t...
The natural history of the nautilid genus Nautilus, composed of a controversial number of extinct and extant species, has been the subject of scientific scrutiny for centuries.
While a great research effort lasting from the mid-1970s to 1990s contributed vast amounts of new information concerning the evolutionary history, current diversity, mode of...
Large collections of well-preserved specimens of the ammonite
Baculites inornatus
Meek (1862) from two lower to middle Campanian localities on the Pacific coast of North America are analyzed quantitatively to examine both variability and evolutionary change of species-level distinguishing characters. To this end, we present a new method of describi...
Ammonoidea were dominant elements of marine Cretaceous faunas. Their fossils are important biostratigraphic indicators, in some cases with worldwide distribution. Their paleobiogeographic distributions were influenced by changing continental positions, currents, sea level change, and perhaps by their mode of life as reflected in the evolution of ma...
Ammonoidea were dominant elements of marine Cretaceous faunas. Their fossils are important biostratigraphic indicators, in some cases with worldwide distribution. Their paleobiogeographic distributions were influenced by changing continental positions, currents, sea level change, and perhaps by their mode of life as reflected in the evolution of ma...
Phyllospadix scouleri is a common seagrass along the rocky intertidal coast of the Pacific Northwest. Previously we established a correlation between increased sulfide and hydrogen sulfide (H2S) and Zostera marina seedling senescence. While Z. marina grows in soft sediment environments, here we evaluate the possibility that P. scouleri may experien...
Severe changes in ocean redox, nutrient cycling, and marine productivity accompanied most Phanerozoic mass extinctions. However, evidence for marine photic zone euxinia (PZE) as a globally important extinction mechanism for the end-Triassic extinction (ETE) is currently lacking. Fossil molecular (biomarker) and nitrogen isotopic records from a sedi...
The extant species of Nautilus and Allonautilus (Cephalopoda) inhabit fore-reef slope environments across a large geographic area of the tropical western Pacific and eastern Indian Oceans. While many aspects of their biology and behavior are now well-documented, uncertainties concerning their current populations and ecological role in the deeper, f...
Renal uroliths (concrements) of calcium phosphate have long been known to exist in both growing and mature (non-growing) Nautilus species, but to date no evidence-based explanation for their existence has been available.The currently favored speculation is that they function as a calciumreserve for shell and septal calcification.Here we present new...
The study presented here examined the effects of administering hydrogen sulfide (H2S) to several ancient extant plant species to determine the organisms’ response to stress. Even though sulfur is an essential macronutrient required for growth and productivity, there are toxic compounds of this element that exert detrimental effects and produce phys...
This study presents a novel way of enhancing plant growth through the use of a non-petroleum based product. We report here that exposing either roots or seeds of multicellular plants to extremely low concentrations of dissolved hydrogen sulfide at any stage of life causes statistically significant increases in biomass including higher fruit yield....
Multiple > 1‰ δ13C isotopic excursions measured across the Cretaceous–Paleogene (K–Pg) boundary in an iridium-bearing stratigraphic section from Mud Buttes, North Dakota, USA, fail to demonstrate an unambiguous chemostratigraphic signal for the extinction. Results of two-sample Kolmogorov–Smirnov tests using δ13C records for the Mud Buttes section...
Models of mass extinctions caused by greenhouse warming depend on the ability of warming to affect the oxygenation of the ocean, either through slowing circulation or changes in biological productivity and the organic carbon budget. Opal Creek, Alberta, Canada is a biostratigraphically continuous Permian–Triassic Boundary (PTB) section deposited in...
Biogeographic patterns of survival help constrain the causal factors responsible for mass extinction. To test whether biogeography influenced end-Cretaceous (K-Pg) extinction patterns, we used a network approach to delimit biogeographic units (BUs) above the species level in a global Maastrichtian database of 329 bivalve genera. Geographic range is...
Supporting information
In quantitative paleobiology, one common format for image-derived information is the closed two-dimensional outline curve. Before the end of the last century a great variety of morphometric tools were on offer to deal with this data type, including diverse analyses of distance from a central point, "eigenshape analysis" of a carefully normalized ta...
Microorganisms are abundant in the upper atmosphere, particularly downwind of arid regions, where winds can mobilize large
amounts of topsoil and dust. However, the challenge of collecting samples from the upper atmosphere and reliance upon culture-based
characterization methods have prevented a comprehensive understanding of globally dispersed air...
Conditions of modern life could be driving changes in the makeup of our genes. Our bodies and our brains may not be the same as those of our descendants
The Permian/Triassic mass extinction marks a permanent phylogenetic shift in the composition of the sessile benthos, from one largely dominated by articulate brachiopods to one dominated by mollusks. Widespread evidence of oceanic hypoxia and anoxia at this time provides a possible selective kill mechanism that could help explain the large taxonomi...
We welcome the fact that [Gastaldo et al. (2009)][1] have been continuing research in the Karoo of South Africa; those of us who have worked there know how important new research in this area is if we are to ever understand the causes of the Permian–Triassic mass extinction on land. However, here
New biostratigraphic data obtained from measured stratigraphic sections of Santonian through Maastrichtian age located along the west coast of North America necessitate changes to the currently accepted chronostratigraphic framework for this region of the North Pacific biotic province. We recognize and/or define 12 molluscan zones over this interva...
Spores of Bacillus subtilis were exposed to a series of stratosphere simulations. In total, five distinct treatments measured the effect of reduced pressure,
low temperature, high desiccation, and intense ultraviolet (UV) irradiation on stratosphere-isolated and ground-isolated B. subtilis strains. Environmental conditions were based on springtime...
Dr. Ward is doing field work in Antarctica till late March 2011 and is out of e-mail, web, and phone contact and unable to submit his abstract till after the deadline. Below is a summary of information from the CITES COP15 ANNOUNCEMENT regarding overharvest and other impacts on the genus Nautilus and the genus Allonautilus. Peter will update and re...
Oxygen through TimeRespiration and BipedalismThe Evolution of the Air Sac SystemDinosaur Survivorship across the Triassic–Jurassic BoundaryOxygen and Dinosaur DiversityConclusions
References
Vertical depth migrations into shallower waters at night by the chambered cephalopod Nautilus were first hypothesized early in the early 20(th) Century. Subsequent studies have supported the hypothesis that Nautilus spend daytime hours at depth and only ascend to around 200 m at night. Here we challenge this idea of a universal Nautilus behavior. U...
Growth rates of immature male and female N. pompilius. A comparison of male (blue diamonds, y = 0.0687x) and female (red squares, y = 0.0648x) growth rates for Nautilus which were immature at both first capture and recapture times. No difference between male and female growth rates is observed.
(EPS)
Small mesh trapping capture results. Twin traps comprising one large mesh (75×50 mm) and one small mesh (30×30 mm) trap ‘piggy backed’ together were deployed on 41 occasions between 100 to 460 m and failed on all occasions to capture any juvenile Nautilus. The large mesh trap caught immature to mature Nautilus at a rate consistent with overall capt...
Comparison table of Nautilus demographic studies. A comprehensive summary of field study data for the Nautilus demographic parameters of shell length, number of septa, male: female ratio and percentage of mature individuals is provided. The data comes from a wide range of studies and locations and covers all extant species of Nautilus known to date...
Overall capture seasonality. Capture seasonality was assessed for three month periods over five years. While a slight increase is apparent in June to August there is no evidence for any seasonal trend in capture rate. Error bars (±1 standard error of the mean) are shown.
(EPS)
Comparison table of Nautilus growth rate studies. Growth, embryonic development period and age estimation data are summarized from field (F), aquarium (A) and radiometric / geochemical (R) studies in the literature. Note the similarity of age estimates for both this study and that of Saunders, the only field-based studies of growth rate.
(DOCX)
Seasonality in ratio of mature male to female captures. Capture numbers and percentage ratio of males to females during three month seasons of the year over five years are compared. Sample numbers were similar for each season and the % male value range from 86.3–93.1% did not vary greatly from the mean value of 89.5%. There is no evidence for seaso...
Nautiloids are the subject of speculation as to their threatened status arising from the impacts of targeted fishing for the ornamental shell market. Life history knowledge is essential to understand the susceptibility of this group to overfishing and to the instigation of management frameworks. This study provides a comprehensive insight into the...
Clastic strata preserved on Sidney Island, Barnes Island, and adjacent islands of the southernmost Gulf Islands of British Columbia and the northern San Juan Islands of Washington State are assigned to new stratigraphic units: the Sidney Island Formation and the Barnes Island Formation. The Sidney Island Formation consists of basal conglomerate and...
The stratigraphy of the Upper Cretaceous Nanaimo Group of the Vancouver Island region is revised on the bases of new fossil and field data. Previously unrecognized turbidite facies of the Haslam Formation are proposed as the new Cowichan Member of the Haslam Formation. This member either overlies or intertongues with the new Haslam Creek Member of...
Episodes of mass extinction represent the largest events of biodiversity loss known in the geologic record, and may provide tests of biodiversity-ecosystem stability hypotheses. Here we present the first correlation between ammonoid diversity and disparity and ecosystem stability as represented by stable carbon isotopic records spanning the end-Per...
While the end-Permian extinction in the marine realm is well known from the Tethys Ocean, it remains little studied in the vast Panthalassic Ocean. Opal Creek, Alberta, Canada is a biostratigraphically continuous Permian-Triassic Boundary (PTB) section that is interpreted to have been deposited in a deep outer shelf setting along the Panthalassic w...
Hydrogen sulfide is not only a potential mass extinction kill mechanism but also a selective agent by which some organisms are preferentially removed. We present investigations into the sensitivity of key marine invertebrate groups.
Microbial diversity in the upper atmosphere remains unexplored. We sampled air over the Pacific Ocean at 20 km using a high altitude aircraft. After culturing isolates in the lab, we explored microbial resistance with ground-based stratosphere simulations.
The origin and evolution of the genus Nautilus have long been obscured by the poor fossil record, by apparent morphological conservatism, and by confusion regarding the
taxonomy of the living species. Studies of protein polymorphisms promise a solution to this impasse, since such variation
reflects the structure of the genes themselves and should r...
Until recently, knowledge of the ecology of Nautilus was largely based on trapping results, observations of captured animals held in shallow water, and speculation and hearsay. Despite the limitations imposed by such sources, a considerable amount of information regarding the depth range, diet, and geographic distribution of Nautilus had been assem...
The shell of Nautilus is commonly thought to be fully mature when it has certain characteristics, namely, a white venter, a thickened apertural edge, a black band along the inside of the aperture, a pronounced ocular sinus on each side, a marked thickening of the final septum, and approximation of the final septa (Stenzel, 1964). This chapter will...
Since the pioneering efforts of Eric Denton and John Gilpin-Brown (1966), much has been learned about the buoyancy system of the chambered Nautilus. It seems timely, therefore, to evaluate critically what is known and not known about the buoyancy system of Nautilus, rather than merely to restate what has gone before. In particular, we will discuss...
Stable sulfur isotopes from the reduced sulfur fraction of Late Triassic-Early Jurassic marine sediments at Kennecott Point in British Columbia, Canada, show evidence for a major perturbation in sulfur cycling coincident with a major carbon cycle perturbation in the wake of a mass extinction event at the Triassic-Jurassic boundary. The δ34S of redu...
A previously uncollected fauna of ammonites, bivalves, and other molluscs, associated with radiolarian microfossils, has been newly recognized near Lawn Hill on the east coast of central Queen Charlotte Islands, British Columbia. The regional biostratigraphic zonation indicates that the Lawn Hill fauna is correlative with the Nostoceras hornbyense...