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Pollen and carbon isotope data from Natural Trap Cave provides insights into the environmental conditions of the Bighorn Basin, in north-central Wyoming, USA during the time intervals 151.1 to 132.2 cal ka BP, 51.8 to 17.4 cal ka BP, and 10.4 cal ka BP to present. Similarities between the buildup of the penultimate and last glacial maxima include abundant Artemisia, Amaranthaceae, Asteraceae, and Poaceae pollen, which, when combined with high δ13C values (>−25.0‰) and low plant discrimination values (18.0–19.0‰) from sedimentary organic matter, indicate steppe-like, cold-dry conditions. Between 151 and 142.5 cal ka BP, abundant Poaceae associated with much lower δ13C values (−28.0‰ to −26.0‰) and higher plant discrimination values (19.0‰–21.0‰) could be indicative of relatively wet summers. Similarly, after 25 cal ka BP increases in Poaceae may indicate wet conditions during the growing season. Holocene conditions differ from the earlier sections of the record, with greater arboreal pollen abundance (i.e., Pinus), consistent with woodland expansion in the region. Carbon isotope data from sedimentary organic matter show the Holocene was more humid than the glacial conditions of the late Pleistocene. This is especially clear at the start of the Holocene when a large negative carbon isotope excursion (CIE

Almost a half-century ago excavations at Natural Trap Cave (NTC) began to yield evidence of the steppe paleoecology along the western slope of the Bighorn Mountains in north central Wyoming. The first decade of fieldwork led to the discovery of a diverse fauna that existed at the end of the Last Glacial Maximum. Stratigraphic deposits below the entrance of the cave were studied soon after excavations began, but never formally published. Although stratigraphy, taphonomy, and depositional circumstances were briefly discussed over the following years, little has been done to correlate the numerous stratigraphic schemes used by various authors. In this study, four stratigraphic sections were measured and analysed to establish an easily modifiable lithostratigraphic system of nomenclature. We provide the first correlations of all stratigraphic nomenclature used throughout excavations at NTC to facilitate comparisons with current and previous collections and publications. By leveraging more than 100 radioisotopic dates we developed an age-depth model and chronostratigraphic framework to further interrogate spatiotemporal relationships between strata, paleoenvironmental proxies, and fossil assemblages. Deposition is shown to be discontinuous; sediment accumulation in the study area is restricted to the buildup through peak penultimate and Last Glacial maxima. More recent (

Turtle (Testudines) tracks, Chelonipus torquatus, reported from the early Middle Triassic (Anisian) of Germany, and Chelonipus isp. from the late Early Triassic (Spathian) of Wyoming and Utah, are the oldest fossil evidence of turtles, but have been omitted in recent discussions of turtle origins. These tracks provide significant clues as to how early the turtle Bauplan originated. Turtle trackways are quite distinctive: the manus and pes form tracks nearly parallel to the midline and indicate an unusually wide gait in which the trackway width is nearly equal to the stride length. These tracks do not fit what would be expected to be made by Triassic Pappochelys or Odontochelys, a supposed prototurtle and an early turtle, respectively. In contrast, these tracks are consistent with what would be expected from the Triassic turtles Proganochelys and Palaeochersis. The features inferred to be present in Triassic turtle tracks support the notion that Odontochelys is a derived aquatic branch of the turtl...

We employed the widely-tested biophysiological modeling software, Niche Mapper™ to investigate the metabolic function of Late Triassic dinosaursPlateosaurusandCoelophysisduring global greenhouse conditions. We tested them under a variety of assumptions about resting metabolic rate, evaluated within six microclimate models that bound paleoenvironmental conditions at 12° N paleolatitude, as determined by sedimentological and isotopic proxies for climate within the Chinle Formation of the southwestern United States. Sensitivity testing of metabolic variables and simulated “metabolic chamber” analyses support elevated “ratite-like” metabolic rates and intermediate “monotreme-like” core temperature ranges in these species of early saurischian dinosaur. Our results suggest small theropods may have needed partial to full epidermal insulation in temperate environments, while fully grown prosauropods would have likely been heat stressed in open, hot environments and should have been restricted to cooler microclimates such as dense forests (under any vegitative cover) or those seen at higher latitudes and elevations. This is in agreement with the Late Triassic fossil record and may have contributed to the latitudinal gap in the Triassic prosauropod record.

The Alcova Limestone is a widely exposed but poorly studied Triassic unit found throughout Wyoming. Although it is used as a regional lithostratigraphic marker bed, the age of the limestone is not well constrained and contention regarding its depositional nature (marine vs. non-marine saline lake) has not been adequately resolved, although the marine hypothesis is more widely accepted. Currently, its age is based on the occurrence of a single basal pistosaurid, Corosaurus alcovensis . We provide the first 87 Sr/ 86 Sr analysis of the Alcova Limestone. The data strongly support a marine origin for this unit. Furthermore, the data provide an age range, based on their placement on the marine strontium curve, that limits the deposition of the Alcova Limestone to the latest Olenekian to earliest Anisian (Early Triassic–Middle Triassic boundary). This placement is consistent with the timing of the Spathian regression recorded in other transitional marine to non-marine strata of the western USA.

A vertebral element assigned to an Apatosaurus cf. ajax from the Late Jurassic Morrison Formation is described. The specimen exhibits an unusual morphology where two vertebrae are nearly seamlessly fused together, including the haemal arch that spans them. This morphology is thought be the result of a developmental abnormality. CT scans of the specimen reveal a thin zone of dorsoventral thickening between the two neural arches consistent with cortical bone. Contrast in internal morphology differentiates the anterior and posterior vertebral bodies with the anterior expressing greater porosity, which increased accommodation for barite-rich calcite precipitation. No vacuities are observed to suggest the former presence of an intervertebral disk or intervertebral joints: the absence of an intervertebral disc or intervertebral joints is indicative of a condition known as block vertebra. Block vertebrae occur with the loss, or inhibition, of somitocoele mesenchyme early in embyogenesis (i.e., during resegmentation of the somites responsible for the formation of the affected vertebra). The derivatives of somitocoele mesenchyme include the intervertebral disc and joints. Although vertebral paleopathologies are not uncommon in the fossil record, this specimen is the first recognized congenital malformation within Sauropoda. Anat Rec, 297:1262–1269, 2014. © 2014 Wiley Periodicals, Inc.

The Lower Triassic Red Peak Formation of the Chugwater Group has long been considered to have an extremely poor paleontological record, although the cause for the apparent dearth of fossils has yet to be been determined. During the course of fieldwork in central Wyoming numerous vertebrate and invertebrate ichnogenera (n ≥ 11) were observed. Vertebrate tracks and trackways representative of dinosauromorph, archosaur, lepidosaur, and testudinate trackmakers were found (cf. Rotodactylus, Chirotherium barthii, Rhynchosauroides, and cf. Chelonipus respectively). An invertebrate ichnoassemblage composed of at least 6 ichnogenera consistent with the Scoyenia ichnofacies were also found (e.g., Diplichnites, Lockeia, Fuersichnus communis, Palaeophycus striatus, cf. Scoyenia, and cf. Scolicia). The majority of these tracks and traces were found in the upper platy facies (upper 10–20 m of the of the Red Peak Formation), which is thought to be no younger than upper Spathian in age. Sedimentary structures, architectural elements, and lateral stratigraphic relationships support the interpretation of floodplain, fluvial, and lacustrine deposition for the upper platy facies in central Wyoming. The Red Peak Formation vertebrate and invertebrate ichnoassemblages, along with their associated depositional environments, are consistent with a fluviolacustrine (continental) setting comparable to those described from Lower to Middle Triassic strata with a Pangean distribution, including the Moenkopi Formation in the southwestern United States. This ichnoassemblage provides the first opportunity to observe paleoecological diversity and associated paleoenvironments within the Lower Triassic of the Chugwater Group.

Small lakes are excellent records of environmental changes and are sensitive to local climate fluctuations. Large lacustrine systems record larger-scale climate events. Wetland deposits also provide high-resolution paleoclimatic and paleoenvironmental data. Although wetland deposits are typically associated with wet climatic conditions, they actually occur in a wide variety of climates. Whereas lakes and wetlands are very sensitive to changes in climate, high-resolution data in these archives are lost unless it is possible to differentiate these deposits from other “floodplain” deposits. Synthesis of micromorphological and geochemical data with facies relationships is critical to accurate interpretations of ancient wetland–lacustrine deposits. This study illustrates how micromorphology and geochemistry, combined with facies relationships, provide a viable method for differentiating complex, ancient wetland–lacustrine subenvironments. A hydrogeomorphological classification is proposed to provide appropriate genetic terminology that is useful in the rock record. Eight Morrison Formation subenvironments within lacustrine depositional successions from north central Wyoming were delineated using this interdisciplinary approach. Subenvironments include shallow-water wetlands, marsh, lacustrine fringe, and fen basin and fringe deposits. Synthesized data indicate that an overall basinal infilling succession was punctuated by 3 major lake contraction events, which were followed by extended periods of landscape stability. Initially balance-filled conditions dominated the shallowing-upward lacustrine deposits such that sediment and water supply, and accommodation space were relatively equal. As the lake basin filled, shallower water, underfilled lake conditions prevailed. The distribution of wetland pedotypes indicates that evapotranspiration remained high, suggesting that a stable, semi-arid to arid climate dominated in this area throughout Morrison time. Also supporting a semi-arid to arid climate are more positive carbon isotopes compared to values for disseminated organic material in the surrounding area, abundant barite nodules, gypsum pseudomorphs, and zeolites. Although major fluctuations in lake level may have resulted from punctuated wetter episodes, synthesized data suggest that overall the climate remained relatively arid to semiarid and the lake basin remained closed throughout most of Morrison time. Fluctuations in lake level likely resulted from a significant increase in recharge in the source area, possibly related to volcanic events rather than a change in climate.

The interaction of metalloproteins with oxides has implications not only for bioanalytical systems and biosensors but also in the areas of biomimetic photovoltaic devices, bioremediation, and bacterial metal reduction. Here, we investigate mitochondrial ferricytochrome c (Cyt c) co-sorption with 0.01 and 0.1 M phosphate on hematite (alpha-Fe2O3) surfaces as a function of pH (2-11). Although Cyt c sorption to hematite in the presence of phosphate is consistent with electrostatic attraction, other forces act upon Cyt c as well. The occurrence of multilayer adsorption, and our AFM observations, suggest that Cyt c aggregates as the pH approaches the Cyt c isoelectric point. In solution, methionine coordination of heme Fe occurs only between pH 3 and 7, but in the presence of phosphate this coordination is retained up to pH 10. Electrochemical evidence for the presence of native Cyt c occurs down to pH 3 and up to pH 10 in the absence of phosphate, and this range is extended to pH 2 and 11 in the presence of phosphate. Cyt c that initially adsorbs to a hematite surface may undergo conformation change and coat the surface with unfolded protein such that subsequently adsorbing protein is more likely to retain the native conformational state. AFM provides evidence for rapid sorption kinetics for Cyt c co-sorbed with 0.01 or 0.1 M phosphate. Cyt c co-sorbed with 0.01 M phosphate appears to unfold on the surface of hematite while Cyt c co-sorbed with 0.1 M phosphate possibly retains native conformation due to aggregation.

Electron transfer between redox active proteins and mineral oxides is important in a variety of natural as well as technological processes, including electron transfer from dissimilatory metal-reducing bacteria to minerals. One of the pathways that could trigger electron transfer between proteins and minerals is redox-linked conformation change. We present electrochemical evidence that mitochondrial cytochrome c (Mcc) undergoes significant conformation change upon interaction with hematite and indium-tin oxide (ITO) surfaces. The apparent adsorption-induced conformation change causes the protein to become more reducing, which makes it able to transfer electrons to the hematite conduction band. Although Mcc is not a protein thought to be involved in interaction with mineral surfaces, it shares (or can be conformed so as to share) some characteristics with multiheme outer-membrane cytochromes thought to be involved in the transfer of electrons from dissimilatory iron-reducing bacteria to ferric minerals during respiration. We present evidence that a 10.1 kDa monohoeme cytochrome isolated and purified from Acidiphilium cryptum, with properties similar to those of Mcc, also undergoes conformation change as a result of interaction with hematite surfaces.

The interaction of metalloproteins such as cytochromes with oxides is of interest for a number of reasons, including molecular catalysis of environmentally important mineral-solution electron transfer reactions (e.g., dehalogenations) and photovoltaic applications. Iron reduction by bacteria, thought to be cytochrome mediated, is of interest for geochemical and environmental remediation reasons. As a baseline for understanding cytochrome interaction with ferric oxide surfaces, we report on the interaction of mitochondrial cytochrome c (Mcc), a well-studied protein, with hematite (α-Fe 2 O 3 ) surfaces. Mcc sorbs strongly to hematite from aqueous solution in a narrow pH range corresponding to opposite charge on Mcc and hematite (between pH 8.5 and 10, Mcc is positively charged and hematite surfaces are negatively charged). Cyclic voltammetry of Mcc using hematite electrodes gives redox potentials characteristic of Mcc in a native conformational state, with no evidence for unfolding on the hematite surface. Atomic force microscopy imaging is consistent with a loosely attached adsorbate that is easily deformed by the AFM tip. In phosphate-containing solution, Mcc adhers to the surface more strongly. These results establish hematite as a viable material for electrochemical and spectroscopic characterization of cytochrome–mineral interaction.

The interaction of cytochromes (heme proteins) with mineral surfaces is important from an environmental perspective (e.g. heavy metal remediation and reductive dehalogenation reactions), for designing biosensors and bioanalytical systems, and for emerging photovoltaic applications. In addition, the cytochrome studied here shares properties with some cytochromes from Fe-reducing bacteria and its general behavior sheds light on how other cytochromes might behave during Fe(III) reduction. The objectives of this study were to characterize the direct electrochemistry and sorption mechanism of horse heart ferricytochrome c (a mitochondrial cytochrome referred to as Hcc) on hematite surfaces as a function of pH, time of sorption and ionic strength. Hcc sorption on hematite mainly occurs between pH 8 and 10, the pH range in which hematite surfaces and Hcc are oppositely charged. Calculated net attractive forces correspond closely with the pH range of peak sorption, suggesting that sorption is mainly electrostatically controlled. Hcc sorption with ionic strength is consistent with this conclusion. The pH-dependent conformation of Hcc sorbed on hematite appears to be different from that in solution as indicated by UV-visible spectroscopy and its more negative reduction potential compared to native Hcc. Sorption kinetics were rapid and pH-independent across the pH range 3–10 with slow conformational changes occurring at >60 h. Our results suggest that the electrostatic attraction of the cytochrome towards the surface orient the cytochrome for favorable electron transfer between the heme group of the cytochrome and hematite.

The Triassic is an extraordinary time interval that experienced a Phanerozoic low in sedimentary packages, a major shift from carbonate to siliciclastic deposition, biotic recovery, the origination of the modern fauna, the peak of Pangaean accretion (and its initial break-up), and the end-Triassic extinction. However, quantification of the sedimentary record is necessary to more fully interrogate the nature of Triassic deposition. To better understand the factors that influenced the formation and preservation of the sedimentary record, this study describes the spatiotemporal distribution of sedimentary packages (and their properties) in the western US; this region preserves the most complete Triassic record in North America. The results demonstrate a significant climatic control on Early Triassic sediment accumulation, which is up to 4.5 times greater than that seen in the more tectonically controlled accumulation of Late Triassic sediment. It is demonstrated that global perturbations in δ13Ccarb closely match variability in the Early Triassic sedimentation rates, volume, and lithology. It is also during this interval that the highest turnover rate of sedimentary packages occurs. In contrast, the Late Triassic has much lower rates of sediment accumulation but greater lithological heterogeneity, including several intervals of coarse-grained sedimentation linked to the initiation of Andean-type subduction along the Cordilleran margin. Further results show that the distribution of sedimentary package duration throughout the Triassic interval is nearly identical to that reported for the entire Phanerozoic. This suggests that tectonic processes that govern package longevity in the Triassic of the western US are similar to those that govern larger-scale patterns across the continent. Quantification of the spatiotemporal distribution of Triassic sediments has provided a framework for comparing the structure of the sedimentary record across this dynamic interval. It is anticipated that this study will be the starting point for further investigations of attributes integral to the Triassic system, including improved studies of mass balance, interrogations of the Middle Triassic problem, and analyses of the preservation and distribution of body and trace fossils essential for understanding biotic recovery and the origins of the modern fauna.

A vertebral element assigned to an Apatosaurus cf. ajax from the Late Jurassic Morrison Formation is described. The specimen exhibits an unusual morphology where two vertebrae are nearly seamlessly fused together, including the haemal arch that spans them. This morphology is thought be the result of a developmental abnormality. CT scans of the specimen reveal a thin zone of dorsoventral thickening between the two neural arches consistent with cortical bone. Contrast in internal morphology differentiates the anterior and posterior vertebral bodies with the anterior expressing greater porosity, which increased accommodation for barite-rich calcite precipitation. No vacuities are observed to suggest the former presence of an intervertebral disk or intervertebral joints: the absence of an intervertebral disc or intervertebral joints is indicative of a condition known as block vertebra. Block vertebrae occur with the loss, or inhibition, of somitocoele mesenchyme early in embyogenesis (i.e., during resegmentation of the somites responsible for the formation of the affected vertebra). The derivatives of somitocoele mesenchyme include the intervertebral disc and joints. Although vertebral paleopathologies are not uncommon in the fossil record, this specimen is the first recognized congenital malformation within Sauropoda. Anat Rec, 297:1262-1269, 2014. © 2014 Wiley Periodicals, Inc.

There are many creatures that capture our imaginationand spark our interest in the evolutionary history of life,but few are as compelling as the great rulers of theMesozoic, the dinosaurs. Many books are available tothe avid student of these extinct icons of evolution,ranging from the encyclopedic (Currie and Padian 1997)to the specific (Carpenter 2000), but few tell the story ofthe ecological stage upon which the dinosaurs danced aswell as Scott D. Sampson.Dinosaur Odyssey: Fossil Threads in the Web of LifeLike many good storytellers, Sampson has firsthandknowledge of his subject. He starts with a personalaccount of an expedition to the island of Madagascar(chapter 1). Throughout the narrative, Sampson weavesa delicate tapestry that includes observations of modernecology, diversity, and environment and links thosethreads to the distant past. In this manner, the reader istakenthrougha worldofintricaterelationshipsdemonstratingthe importance and function of the often-overlooked playersof the dinosaurian stage. All of the players, whether microbeor Monolophosaurus, are given their time in the spotlight,providing a contextual framework that makes the dinosaurodyssey all the more fascinating.Imagine three stories, one of climate, geography, andevolution, a second composed of hidden faunal playersand other ecological components (think poop, soil, worms,insects, and bacteria), and the last featuring the stars of theshow: dinosaurs. The three storylines are integral to oneanother, and the book is written so that each successivestory incorporates componentsof previous chapters.In moreways than one, the interwoven organization of Sampson’sbook mirrors the natural world it attempts to portray.The first third of the book (chapters 1–6) takes a broadapproach to understanding biological complexities and con-tingencies throughout Earth’s dynamic history. The reader istaken on a journey that explores paleoclimate, tectonics,global nutrient cycling, and the importance of the trophicpyramid in paleoecology. Along the journey, the functionalrole of primary producers who convert sunlight into aneffective ecological currency is further investigated, alongwith characteristics that define what a dinosaur is (andisn’t!). Sampson smoothly discusses evolutionary theorythrough several guided examples that relate ecology anddinosaurs to the fundamental concepts of natural selection.The middle third of the book (chapters 7–11) begins totruly delve into the details surrounding the environment,anatomy, and physiology of several major groups of dino-saurs and their supporting ecological cast. In this section,Sampson further weaves together various strands of thenatural world, such as the flow of energy from plants toherbivores to carnivores and back through a myriad ofinteractions and processes. This portion of the book alsoincludes a wonderful discussion of dinosaur behavior andbiology, including feeding mechanics, metabolism andgrowth, hunting, and reproduction.By this point, the reader has toured multiple ecologicalfacets of the prehistoric world, from plants harnessing thesun’s energy to higher up the trophic ladder, through thedigestive tract of a carnivorous dinosaur and out the otherend, only to be recycled once more. The last third of thebook (chapters 12–15) pulls all of these strands togetheruntil the reader sees a completed picture of the rulers of

Keywords Owen.Huxley.Philosophy of science.Ape brain debate.Humanistic perspectiveIn the years immediately following the 1859 publication ofDarwin’s Origin of Species (Darwin 1859), a disagreementover man’s place in nature and his relationship to the greatapes was debated between two iconic nineteenth-centuryscientists, Richard Owen and Thomas Henry Huxley.Though many readers will likely be familiar with the clashbetween Darwin’s critics and defenders such as Huxley,who was famously sharpening his claws and beak inreadiness, few are likely to be as conversant with thehistory and philosophy underlying the arguments. Christo-pher E. Cosans’ Owen’s Ape and Darwin’s Bulldog: BeyondDarwinism and Creationism was published on the 150thanniversary of Mr. Darwin’s Origin and tells a detailedstory of the historical, philosophical, economic, and culturalstage upon which the “ape brain debate” between Owenand Huxley ensued.Similar to both Huxley and Owen, Christopher Cosanshas a firsthand perspective of the importance of anatomicaldissection and its place in the study of the relationshipsbetween organisms; in fact he has gone so far as toreproduce the dissections that originally demonstrated theanatomical structures central to the ape brain debate. It islaudable that a philosopher of science is so well versed inthe skills of the “dirty dissecting theatre.” Ultimately,Cosans leads the reader through a maze of philosophicalterminology and concepts all the while using the Huxley–Owen debate as a vehicle to demonstrate the differencesbetween scientific materialism and the humanistic realistperspective and how they relate to modern science, ethics,and society.Cosans begins by taking the reader on a journeythrough nineteenth-century Western philosophy of sci-ence with the parable of the “hippopotamus major” inCharles Kingsley’s The Water-Babies (Kingsley 1863)asa tool to explain the differences between scientific andhumanistic thinking, which in the end is the central themeof Owen’sApe.In the first half of the book (chapters 2–4) the reader isimmersed in the philosophical ideas that surround theanatomical discussions regarding the similarities and differ-ences in the brains of ape and man. The anatomicalobservations that Owen published prior to Darwin’s Originhighlight features that differentiate man from ape, placinghim in a subclass of mammal well removed from an apeancestor. In these chapters Cosans counters social construc-tivism critiques that suggest Owen’s views were inopposition to social reform, exemplified primarily in theworks of Adrian Desmond (1986, 1992). All the whileCosans clearly demonstrates how Owen dealt with the issueof race by using non-European specimens such as thecrania of Papuans to typify man, providing strong support“that the difference between Papuan and adult ape skullsovershadows any difference between Papuans and Euro-peans” (pg. 52). Considering the broader context of hownineteenth-century biologists viewed the human races,Cosans summarizes Owen’s view “that, compared to apes