A new talpid from the late Eocene of North America

Abstract: The origin and early evolution of talpids (moles, shrew-moles, and desmans) is not well understood, in large part due to the poor fossil record of early talpids. Here we report the oldest known talpid from North America, Oreotalpa florissantensis gen. et sp. nov., based upon a tiny dentary with m1-m3 discovered in upper Eocene (Chadronian) strata of the Florissant Formation, Florissant Fossil Beds National Monument, Colorado. Oreotalpa extends the North American record of talpids back by some six Ma and appears temporally correlative with the oldest documented talpids from the late Eocene of Europe. While others have postulated a Eurasian origin for talpids, discovery of Oreotalpa suggests that the evolution of the group was underway in North America by late Eocene time and raises the possibility of a North American origin.


PAST: PALEONTOLOGICAL STATISTICS SOFTWARE PACKAGE FOR EDUCATION AND DATA ANALYSIS

Abstract: A comprehensive, but simple-to-use software package for executing a range of standard numerical analysis and operations used in quantitative paleontology has been developed. The program, called PAST (PAleontological STatistics), runs on standard Windows computers and is available free of charge. PAST integrates spreadsheet-type data entry with univariate and multivariate statistics, curve fitting, timeseries analysis, data plotting, and simple phylogenetic analysis. Many of the functions are specific to paleontology and ecology, and these functions are not found in standard, more extensive, statistical packages. PAST also includes fourteen case studies (data files and exercises) illustrating use of the program for paleontological problems, making it a complete educational package for courses in quantitative methods.

paleontological statistics
data analysis
program
past
pca


Histology of “placoderm” dermal skeletons: Implications for the nature of the ancestral gnathostome

Abstract: The vertebrate dermal skeleton has long been interpreted to have evolved from a primitive condition exemplified by chondrichthyans. However, chondrichthyans and osteichthyans evolved from an ancestral gnathostome stem‐lineage in which the dermal skeleton was more extensively developed. To elucidate the histology and skeletal structure of the gnathostome crown‐ancestor we conducted a histological survey of the diversity of the dermal skeleton among the placoderms, a diverse clade or grade of early jawed vertebrates. The dermal skeleton of all placoderms is composed largely of a cancellar architecture of cellular dermal bone, surmounted by dermal tubercles in the most ancestral clades, including antiarchs. Acanthothoracids retain an ancestral condition for the dermal skeleton, and we record its secondary reduction in antiarchs. We also find that mechanisms for remodeling bone and facilitating different growth rates between adjoining plates are widespread throughout the placoderms. J. Morphol., 2013. © 2013 Wiley Periodicals, Inc.


The late Middle Pleistocene hominin fossil record of eastern Asia: synthesis and review.

Abstract: Traditionally, Middle Pleistocene hominin fossils that cannot be allocated to Homo erectus sensu lato or modern H. sapiens have been assigned to different specific taxa. For example, in eastern Asia, these hominin fossils have been classified as archaic, early, or premodern H. sapiens. An increasing number of Middle Pleistocene hominin fossils are currently being assigned to H. heidelbergensis. This is particularly the case for the African and European Middle Pleistocene hominin fossil record. There have been suggestions that perhaps the eastern Asian late Middle Pleistocene hominins can also be allocated to the H. heidelbergensis hypodigm. In this article, I review the current state of the late Middle Pleistocene hominin fossil record from eastern Asia and examine the various arguments for assigning these hominins to the different specific taxa. The two primary conclusions drawn from this review are as follows: 1) little evidence currently exists in the eastern Asian Middle Pleistocene hominin fossil record to support their assignment to H. heidelbergensis; and 2) rather than add to the growing list of hominin fossil taxa by using taxonomic names like H. daliensis for northeast Asian fossils and H. mabaensis for Southeast Asian fossils, it is better to err on the side of caution and continue to use the term archaic H. sapiens to represent all of these hominin fossils. What should be evident from this review is the need for an increase in the quality and quantity of the eastern Asian hominin fossil data set. Fortunately, with the increasing number of large-scale multidisciplinary paleoanthropological field and laboratory research projects in eastern Asia, the record is quickly becoming better understood.


Homologous shell microstructures in Cambrian hyoliths and molluscs

Abstract: Hyoliths were among the earliest biomineralizing metazoans in Palaeozoic marine environments. They have been known for two centuries and widely assigned to lophotrochozoans. However, their origin and relationships with modern lophotrochozoan clades have been a longstanding palaeontological controversy. Here, we provide broad microstructural data from hyolith conchs and opercula from the lower Cambrian Xinji Formation of North China, including two hyolithid genera and four orthothecid genera as well as unidentified opercula. Results show that most hyolith conchs contain a distinct aragonitic lamellar layer that is composed of foliated aragonite, except in the orthothecid New taxon 1 that has a crossed foliated lamellar microstructure. Opercula are mostly composed of foliated aragonite and occasionally foliated calcite. These blade or lath‐like microstructural fabrics coincide well with biomineralization of Cambrian molluscs rather than lophophorates, as exemplified by the Cambrian members of the tommotiid‐brachiopod linage. Accordingly, we propose that hyoliths and molluscs might have inherited their biomineralized skeletons from a non‐mineralized or weakly mineralized common ancestor rather than as a result of convergence. Consequently, from the view of biomineralization, the homologous shell microstructures in Cambrian hyoliths and molluscs strongly strengthen the phylogenetic links between the two groups.


No Ancient DNA Damage in Actinobacteria from the Neanderthal Bone

Abstract: Background The Neanderthal genome was recently sequenced using DNA extracted from a 38,000-year-old fossil. At the start of the project, the fraction of mammalian and bacterial DNA in the sample was estimated to be <6% and 9%, respectively. Treatment with restriction enzymes prior to sequencing increased the relative proportion of mammalian DNA to 15%, but the large majority of sequences remain uncharacterized. Principal Findings Our taxonomic profiling of 3.95 Gb of Neanderthal DNA isolated from the Vindija Neanderthal Vi33.16 fossil showed that 90% of about 50,000 rRNA gene sequence reads were of bacterial origin, of which Actinobacteria accounted for more than 75%. Actinobacteria also represented more than 80% of the PCR-amplified 16S rRNA gene sequences from a cave sediment sample taken from the same G layer as the Neanderthal bone. However, phylogenetic analyses did not identify any sediment clones that were closely related to the bone-derived sequences. We analysed the patterns of nucleotide differences in the individual sequence reads compared to the assembled consensus sequences of the rRNA gene sequences. The typical ancient nucleotide substitution pattern with a majority of C to T changes indicative of DNA damage was observed for the Neanderthal rRNA gene sequences, but not for the Streptomyces-like rRNA gene sequences. Conclusions/Significance Our analyses suggest that the Actinobacteria, and especially members of the Streptomycetales, contribute the majority of sequences in the DNA extracted from the Neanderthal fossil Vi33.16. The bacterial DNA showed no signs of damage, and we hypothesize that it was derived from bacteria that have been enriched inside the bone. The bioinformatic approach used here paves the way for future studies of microbial compositions and patterns of DNA damage in bacteria from archaeological bones. Such studies can help identify targeted measures to increase the relative amount of endogenous DNA in the sample.

dna damage
actinobacteria
neanderthal bone


Tissue-specific geometry and chemistry of modern and fossilized melanosomes reveal internal anatomy of extinct vertebrates

Abstract: Significance Recent reports of nonintegumentary melanosomes in fossils hint at functions for melanin beyond color production, but the biology and evolution of internal melanins are poorly understood. Our results show that internal melanosomes are widespread in diverse fossil and modern vertebrates and have tissue-specific geometries and metal chemistries. Tissue-specific chemical signatures can persist in fossils despite some diagenetic overprint, allowing the reconstruction of internal soft-tissue anatomy in fossil vertebrates, and suggest that links between melanin and metal regulation have deep evolutionary origins in vertebrates. Recent discoveries of nonintegumentary melanosomes in extant and fossil amphibians offer potential insights into the physiological functions of melanin not directly related to color production, but the phylogenetic distribution and evolutionary history of these internal melanosomes has not been characterized systematically. Here, we present a holistic method to discriminate among melanized tissues by analyzing the anatomical distribution, morphology, and chemistry of melanosomes in various tissues in a phylogenetically broad sample of extant and fossil vertebrates. Our results show that internal melanosomes in all extant vertebrates analyzed have tissue-specific geometries and elemental signatures. Similar distinct populations of preserved melanosomes in phylogenetically diverse vertebrate fossils often map onto specific anatomical features. This approach also reveals the presence of various melanosome-rich internal tissues in fossils, providing a mechanism for the interpretation of the internal anatomy of ancient vertebrates. Collectively, these data indicate that vertebrate melanins share fundamental physiological roles in homeostasis via the scavenging and sequestering of metals and suggest that intimate links between melanin and metal metabolism in vertebrates have deep evolutionary origins.

geometry
melanosome
vertebrate
metal
integumentary tissue


Evolution of humeral microanatomy and lifestyle in amniotes, and some comments on palaeobiological inferences

Abstract: A study on the most exhaustive taxonomic sample of amniotes (75 extant and nine extinct taxa) of any quantitative work on this topic published so far demonstrates a strong relationship between lifestyle (aquatic, amphibious or terrestrial) and humeral microanatomy. We suggest that corrections for multiple testing be used to check for statistical artefacts in the context of a phylogenetic independent contrast analysis, and we use the false discovery rate procedure for this. Linear discriminant models segregate the various lifestyles with excellent success rate of up to 98.5%. Lifestyle was thus inferred for six extinct taxa of uncertain habitat. The results obtained suggest that Captorhinus, Claudiosaurus, and Placodus were amphibious, whereas Neusticosaurus and Mesosaurus were aquatic. Lystrosaurus may have been more aquatic than previously suggested, although the results of our inference models have to be integrated with other sources of data, which suggest that it may have been amphibious, rather than aquatic (as a literal interpretation of the models would suggest). Finally, we propose an alternative method of palaeobiological inference for hypothetical ancestors. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 384–406.

humeral microanatomy
lifestyle
amniote
aquatic lifestyle


Biology of the sauropod dinosaurs: the evolution of gigantism

Abstract: The herbivorous sauropod dinosaurs of the Jurassic and Cretaceous periods were the largest terrestrial animals ever, surpassing the largest herbivorous mammals by an order of magnitude in body mass. Several evolutionary lineages among Sauropoda produced giants with body masses in excess of 50 metric tonnes by conservative estimates. With body mass increase driven by the selective advantages of large body size, animal lineages will increase in body size until they reach the limit determined by the interplay of bauplan, biology, and resource availability. There is no evidence, however, that resource availability and global physicochemical parameters were different enough in the Mesozoic to have led to sauropod gigantism.

sauropod dinosaur
gigantism
terrestrial animal
body size
biology


Systematic description of putative animal fossils from the early Ediacaran Lantian Formation of South China

Abstract: The early Ediacaran Lantian Formation in South China contains some of the oldest known representatives of morphologically complex macroorganisms, including various macroalgae and putative animals. The macroalgal fossils have been described previously in several publications, but no taxonomic treatment has been published for the putative animal fossils. This hampers our ability to fully evaluate and communicate the significance of these potentially important Ediacaran macrofossils. To address this deficiency, here we provide a systematic description of these putative animal fossils from the Lantian Formation, including four new genera and five new species: Lantianella laevis gen. et sp. nov., L. annularis gen. et sp. nov., Piyuania cyathiformis gen. et sp. nov., Qianchuania fusiformis gen. et sp. nov. and Xiuningella rara gen. et sp. nov. Morphological comparisons of these fossils and potential modern analogues are provided and critically assessed.

animal fossil
lantian formation
south china


Humble origins for a successful strategy: complete enrolment in early Cambrian olenellid trilobites

Abstract: Trilobites are typified by the behavioural and morphological ability to enrol their bodies, most probably as a defence mechanism against adverse environmental conditions or predators. Although most trilobites could enrol at least partially, there is uncertainty about whether olenellids—among the most phylogenetically and stratigraphically basal representatives—could perform this behaviour because of their poorly caudalized trunk and scarcity of coaptative devices. Here, we report complete—but not encapsulating—enrolment for the olenellid genus Mummaspis from the early Cambrian Mural Formation in Alberta, the earliest direct evidence of this strategy in the fossil record of polymerid trilobites. Complete enrolment in olenellids was achieved through a combination of ancestral morphological features, and thus provides new information on the character polarity associated with this key trilobite adaptation.


Formation of the Isthmus of Panama

Abstract: Independent evidence from rocks, fossils, and genes converge on a cohesive narrative of isthmus formation in the Pliocene. The formation of the Isthmus of Panama stands as one of the greatest natural events of the Cenozoic, driving profound biotic transformations on land and in the oceans. Some recent studies suggest that the Isthmus formed many millions of years earlier than the widely recognized age of approximately 3 million years ago (Ma), a result that if true would revolutionize our understanding of environmental, ecological, and evolutionary change across the Americas. To bring clarity to the question of when the Isthmus of Panama formed, we provide an exhaustive review and reanalysis of geological, paleontological, and molecular records. These independent lines of evidence converge upon a cohesive narrative of gradually emerging land and constricting seaways, with formation of the Isthmus of Panama sensu stricto around 2.8 Ma. The evidence used to support an older isthmus is inconclusive, and we caution against the uncritical acceptance of an isthmus before the Pliocene.


Periodontal Ligament, Cementum, and Alveolar Bone in the Oldest Herbivorous Tetrapods, and Their Evolutionary Significance

Abstract: Tooth implantation provides important phylogenetic and functional information about the dentitions of amniotes. Traditionally, only mammals and crocodilians have been considered truly thecodont, because their tooth roots are coated in layers of cementum for anchorage of the periodontal ligament, which is in turn attached to the bone lining the alveolus, the alveolar bone. The histological properties and developmental origins of these three periodontal tissues have been studied extensively in mammals and crocodilians, but the identities of the periodontal tissues in other amniotes remain poorly studied. Early work on dental histology of basal amniotes concluded that most possess a simplified tooth attachment in which the tooth root is ankylosed to a pedestal composed of “bone of attachment”, which is in turn fused to the jaw. More recent studies have concluded that stereotypically thecodont tissues are also present in non-mammalian, non-crocodilian amniotes, but these studies were limited to crown groups or secondarily aquatic reptiles. As the sister group to Amniota, and the first tetrapods to exhibit dental occlusion, diadectids are the ideal candidates for studies of dental evolution among terrestrial vertebrates because they can be used to test hypotheses of development and homology in deep time. Our study of Permo-Carboniferous diadectid tetrapod teeth and dental tissues reveal the presence of two types of cementum, periodontal ligament, and alveolar bone, and therefore the earliest record of true thecodonty in a tetrapod. These discoveries in a stem amniote allow us to hypothesize that the ability to produce the tissues that characterize thecodonty in mammals and crocodilians is very ancient and plesiomorphic for Amniota. Consequently, all other forms of tooth implantation in crown amniotes are derived arrangements of one or more of these periodontal tissues and not simply ankylosis of teeth to the jaw by plesiomorphically retaining “bone of attachment”, as previously suggested.

cementum
tooth
tissue
periodontal ligament
archosaur


Deep learning and taphonomy: high accuracy in the classification of cut marks made on fleshed and defleshed bones using convolutional neural networks

Abstract: Accurate identification of bone surface modifications (BSM) is crucial for the taphonomic understanding of archaeological and paleontological sites. Critical interpretations of when humans started eating meat and animal fat or when they started using stone tools, or when they occupied new continents or interacted with predatory guilds impinge on accurate identifications of BSM. Until now, interpretations of Plio-Pleistocene BSM have been contentious because of the high uncertainty in discriminating among taphonomic agents. Recently, the use of machine learning algorithms has yielded high accuracy in the identification of BSM. A branch of machine learning methods based on imaging, computer vision (CV), has opened the door to a more objective and accurate method of BSM identification. The present work has selected two extremely similar types of BSM (cut marks made on fleshed an defleshed bones) to test the immense potential of artificial intelligence methods. This CV approach not only produced the highest accuracy in the classification of these types of BSM until present (95% on complete images of BSM and 88.89% of images of only internal mark features), but it also has enabled a method for determining which inconspicuous microscopic features determine successful BSM discrimination. The potential of this method in other areas of taphonomy and paleobiology is enormous.


Dental morphology and variation in theropod dinosaurs: implications for the taxonomic identification of isolated teeth.

Abstract: Isolated theropod teeth are common Mesozoic fossils and would be an important data source for paleoecology biogeography if they could be reliably identified as having come from particular taxa. However, obtaining identifications is confounded by a paucity of easily identifiable characters. Here we discuss a quantitative methodology designed to provide defensible identifications of isolated teeth using Tyrannosaurus as a comparison taxon. We created a standard data set based as much as possible on teeth of known taxonomic affinity against which to compare isolated crowns. Tooth morphology was described using measured variables describing crown length, base length and width, and derived variables related to basal shape, squatness, mesial curve shape, apex location with respect to base, and denticle size. Crown curves were described by fitting the power function Y = a + bX(0.5) to coordinate data collected from lateral-view images of mesial curve profiles. The b value from these analyses provides a measure of curvature. Discriminant analyses compared isolated teeth of various taxonomic affinities against the standard. The analyses classified known Tyrannosaurus teeth with Tyrannosaurus and separated most teeth known not to be Tyrannosaurus from Tyrannosaurus. They had trouble correctly classifying teeth that were very similar to Tyrannosaurus and for which there were few data in the standard. However, the results indicate that expanding the standard should facilitate the identification of numerous types of isolated theropod teeth.

identification
tooth
width
denticle size
theropod tooth


Fidelity of variation in species composition and diversity partitioning by death assemblages: time-averaging transfers diversity from beta to alpha levels

Abstract: Abstract Despite extensive paleoecological analyses of spatial and temporal turnover in species composition, the fidelity with which time-averaged death assemblages capture variation in species composition and diversity partitioning of living communities remains unexplored. Do death assemblages vary in composition between sites to a lesser degree than do living assemblages, as would be predicted from time-averaging? And is the higher number of species observed in death relative to living assemblages reduced with increasing spatial scale? We quantify the preservation of spatial and temporal variation in species composition using 11 regional data sets based on samples of living molluscan communities and their co-occurring time-averaged death assemblages. (1) Compositional dissimilarities among living assemblages (LA) within data sets are significantly positively rank-correlated to dissimilarities among counterpart pairs of death assemblages (DA), demonstrating that pairwise dissimilarity within a study area has a good preservation potential in the fossil record. Dissimilarity indices that downplay the abundance of dominant species return the highest live-dead agreement of variation in species composition. (2) The average variation in species composition (average dissimilarity) is consistently smaller in DAs than in LAs (9 of 11 data sets). This damping of variation might arise from DAs generally having a larger sample size, but the reduction by ∼10–20% mostly persists even in size-standardized analyses (4 to 7 of 11 data sets, depending on metric). Beta diversity expressed by the number of compositionally distinct communities is also significantly reduced in death assemblages in size-standardized analyses (by ∼25%). This damping of variation and reduction in beta diversity is in accord with the loss of temporal resolution expected from time-averaging, without invoking taphonomic bias (from differential preservation or postmortem transportation) or sample-size effects. The loss of temporal resolution should directly reduce temporal variation, and assuming time-for-space substitution owing to random walk within one habitat and/or temporal habitat shifting, it also decreases spatial variation in species composition. (3) DAs are more diverse than LAs at the alpha scale, but the difference is reduced at gamma scales because partitioning of alpha and beta components differs significantly between LAs and DAs. This indicates that the effects of time-averaging are reduced with increasing spatial scale. Thus, overall, time-averaged molluscan DAs do capture variation among samples of the living assemblage, but they tend to damp the magnitude of variation, making them a conservative means of inferring change over time or variation among regions in species composition and diversity. Rates of temporal and spatial species turnover documented in the fossil record are thus expected to be depressed relative to the turnover rates that are predicted by models of community dynamics, which assume higher temporal resolution. Finally, the capture by DAs of underlying variation in the LA implies little variation in the net preservation potential of death assemblages across environments, despite the different taphonomic pathways suggested by taphofacies studies.

species composition
death assemblage
fidelity


Paleohaemoproteus burmacis gen. n., sp. n. (Haemospororida: Plasmodiidae) from an Early Cretaceous biting midge (Diptera: Ceratopogonidae)

Abstract: Paleohaemoproteus burmacis gen. n., sp. n. (Haemospororida: Plasmodiidae) is described from the abdominal cavity of a female biting midge (Diptera: Ceratopogonidae) preserved in 100 million year old amber from Myanmar (Burma). The description is based on the developmental stages of oocysts and sporozoites. The fossil species differs from extant species of Haemoproteus by its wide range of oocyst sizes, small sporozoites and occurrence in an extinct species of biting midge. Numerous sporozoites in the abdominal cavity suggest that the biting midge was an effective vector of this malarial parasite. Characters of the biting midge suggest that the host was a large, cold-blooded vertebrate. This is the earliest record of a malaria parasite and first indication that Early Cretaceous reptiles were infected with haemosporidial parasites.


Supplement to the Burmese (Myanmar) amber checklist and bibliography, 2020

Abstract: This is a supplement to the Burmese (Myanmar) amber checklist and bibliography covering taxa described or recorded during 2020, plus a few earlier records that were missed previously. Up to the end of 2020, 1,859 species were recorded from Kachin amber of which 362 were named in 2020, which is the highest number of species named from any kind of amber in one year. Two species were also named from older Hkamti amber.


Trace fossils in the aftermath of mass extinction events

Abstract: Abstract Ichnology has great potential to advance our understanding of mass extinction events and yet is currently an underutilized resource in such studies. Here we review published ichnological studies for the Ordovician-Silurian, Permian-Triassic and Cretaceous-Tertiary extinction-recovery intervals. In addition, new information regarding the Triassic-Jurassic ichnological record from England, Austria and the western USA is presented. Trace fossils provide important information on the ecological response of the benthic community at such times. In the immediate post-extinction aftermath, the ichnodiversity, burrow size, depth of bioturbation, and ichnofabric index of the sediments are all much reduced. There is an increase in all these parameters through the post-extinction recovery period. In some cases, the stepwise reappearance of certain distinctive ichnotaxa (e.g. Diplocraterion, Rhizocorallium and Thalassinoides) may be of some stratigraphic use. Evidence from Permian-Triassic studies indicates that recovery took longer at low (tropical) palaeolatitudes than mid-high palaeolatitudes. Trace fossils also provide important information on palaeoenvironmental change through the extinction-recovery interval. The application of ichnology to mass extinction studies is in its infancy, but should prove a valuable tool in future research.

aftermath
mass extinction event
trace fossil


Empirical Relationships Between Elevation and the Stable Isotope Composition of Precipitation and Surface Waters: Considerations for Studies of Paleoelevation Change

Abstract: A compilation of 68 studies from throughout many of the world9s mountain belts reveals an empirically consistent and linear relationship between change in elevation and change in the isotopic composition of precipitation along altitudinal transects. The isotopic composition of precipitation decreases linearly with increasing elevation in most regions of the world except in the Himalayas and at elevations >5000 m. There are no significant differences in isotopic lapse rates from most regions of the world (∼0.28 permil/100 m) except at the extreme latitudes where isotopic lapse rates are higher. Given information on past changes in the isotopic composition of precipitation preserved in pedogenic or authigenic minerals, this global isotopic lapse rate can be used to place numerical constraints on the topographic development of some ancient mountain belts or plateaus. There are many complicating factors that can confound interpretation of paleoelevation change based on stable isotopes, and many of these are unique to specific mountain belts or time periods. Relevant to all stable isotope based paleoelevation change studies is the temperature dependent isotope fractionation between a pedogenic or authigenic mineral and the water from which it forms. In cases where isotopic proxy minerals are sampled from localities where temperature will change simultaneously with elevation change, the apparent change in the isotopic composition of precipitation may be dampened by several permil. This suggests that samples taken from the rainshadow side of an emerging orographic barrier may be more likely to preserve isotopic changes resulting from mountain uplift than samples taken from atop a rising mountain range or plateau.

elevation
precipitation
paleoelevation change


EPOFIX AND VACUUM: AN EASY METHOD TO MAKE CASTS OF HARD SUBSTRATES

Abstract: An effective and fast procedure is presented for making transparent casts of hard substrates such as bones, rock, shells, and wood. The procedure is based on a twocomponent epoxy (Epofix) that is especially suitable for cold mounting, avoiding heat, and limiting pressure impregnation that might damage fragile substrates. Critical to successful casting is the use of a vacuum chamber or a vacuum desiccator during early hardening to eliminate air bubbles. The vacuum is interrupted and turned on again to force air out and epoxy into blindending cavities; this action may be repeated. Afterward, the hardening takes place at atmospheric pressure. Unlike other embedding procedures, neither infiltration phases nor acetone "boiling" are necessary to produce detailed casts that are suitable for studies at micron scale and for long-term use.


Combining ZooMS and zooarchaeology to study Late Pleistocene hominin behaviour at Fumane (Italy)

Abstract: Collagen type I fingerprinting (ZooMS) has recently been used to provide either palaeoenvironmental data or to identify additional hominin specimens in Pleistocene contexts, where faunal assemblages are normally highly fragmented. However, its potential to elucidate hominin subsistence behaviour has been unexplored. Here, ZooMS and zooarchaeology have been employed in a complementary approach to investigate bone assemblages from Final Mousterian and Uluzzian contexts at Fumane cave (Italy). Both approaches produced analogous species composition, but differ significantly in species abundance, particularly highlighted by a six fold-increase in the quantity of Bos/Bison remains in the molecularly identified component. Traditional zooarchaeological methods would therefore underestimate the proportion of Bos/Bison in these levels to a considerable extent. We suggest that this difference is potentially due to percussion-based carcass fragmentation of large Bos/Bison bone diaphyses. Finally, our data demonstrates high variability in species assignment to body size classes based on bone cortical thickness and fragment size. Thus, combining biomolecular and traditional zooarchaeological methods allows us to refine our understanding of bone assemblage composition associated with hominin occupation at Fumane.


Error rates and observer bias in dental microwear analysis using light microscopy

Abstract: Despite the increased use of light microscopy in microwear analysis, studies that recognize observer error are scarce. Nonetheless, microwear analysis based on light microscopy may be more prone to observer bias than SEM or confocal microscopy. We measured observer error among five observers, who independently analyzed identical sets of dental wear surfaces on digital micrographs taken through a light microscope. For experienced microscopists, error in light-microscope-based microwear was of a similar magnitude to error rates for SEM-based microwear methods. Significant intraobserver error was rare among the most experienced observers and higher among inexperienced observers. However, because observers develop familiarity when repeatedly analyzing the same image, intraobserver error measured here and in other similar SEM studies may be artificially low. Interobserver error was highly significant and did not appear to diminish with experience. Nonetheless, the data collected by all observers was highly correlated. Essentially all observers found similar microwear differences between the species analyzed, even though the absolute values in the data were observer dependent. Going forward, microwear results will be more robust if observers adopt methods that ensure observer blindness, and avoid the common practice of combining data from different observers, and even from one observer when the observarions are separated by time and experience. Rather than using pre-published microwear databases of extant species as a basis for interpreting paleodiet, researchers may be better served by building shared microwear image libraries, with which observers could generate their own data for the basis of making paleodietary inferences.

observer bias
microwear analysis
light microscopy


True single-molecule DNA sequencing of a pleistocene horse bone.

Abstract: Second-generation sequencing platforms have revolutionized the field of ancient DNA, opening access to complete genomes of past individuals and extinct species. However, these platforms are dependent on library construction and amplification steps that may result in sequences that do not reflect the original DNA template composition. This is particularly true for ancient DNA, where templates have undergone extensive damage post-mortem. Here, we report the results of the first "true single molecule sequencing" of ancient DNA. We generated 115.9 Mb and 76.9 Mb of DNA sequences from a permafrost-preserved Pleistocene horse bone using the Helicos HeliScope and Illumina GAIIx platforms, respectively. We find that the percentage of endogenous DNA sequences derived from the horse is higher among the Helicos data than Illumina data. This result indicates that the molecular biology tools used to generate sequencing libraries of ancient DNA molecules, as required for second-generation sequencing, introduce biases into the data that reduce the efficiency of the sequencing process and limit our ability to fully explore the molecular complexity of ancient DNA extracts. We demonstrate that simple modifications to the standard Helicos DNA template preparation protocol further increase the proportion of horse DNA for this sample by threefold. Comparison of Helicos-specific biases and sequence errors in modern DNA with those in ancient DNA also reveals extensive cytosine deamination damage at the 3' ends of ancient templates, indicating the presence of 3'-sequence overhangs. Our results suggest that paleogenomes could be sequenced in an unprecedented manner by combining current second- and third-generation sequencing approaches.

dna
pleistocene horse bone
third-generation


Laser-Stimulated Fluorescence in Paleontology

Abstract: Fluorescence using ultraviolet (UV) light has seen increased use as a tool in paleontology over the last decade. Laser-stimulated fluorescence (LSF) is a next generation technique that is emerging as a way to fluoresce paleontological specimens that remain dark under typical UV. A laser’s ability to concentrate very high flux rates both at the macroscopic and microscopic levels results in specimens fluorescing in ways a standard UV bulb cannot induce. Presented here are five paleontological case histories that illustrate the technique across a broad range of specimens and scales. Novel uses such as back-lighting opaque specimens to reveal detail and detection of specimens completely obscured by matrix are highlighted in these examples. The recent cost reductions in medium-power short wavelength lasers and use of standard photographic filters has now made this technique widely accessible to researchers. This technology has the potential to automate multiple aspects of paleontology, including preparation and sorting of microfossils. This represents a highly cost-effective way to address paleontology's preparatory bottleneck.

paleontology
lsf
matrix
laser-stimulated fluorescence


Millennial-scale faunal record reveals differential resilience of European large mammals to human impacts across the Holocene

Abstract: The use of short-term indicators for understanding patterns and processes of biodiversity loss can mask longer-term faunal responses to human pressures. We use an extensive database of approximately 18 700 mammalian zooarchaeological records for the last 11 700 years across Europe to reconstruct spatio-temporal dynamics of Holocene range change for 15 large-bodied mammal species. European mammals experienced protracted, non-congruent range losses, with significant declines starting in some species approximately 3000 years ago and continuing to the present, and with the timing, duration and magnitude of declines varying individually between species. Some European mammals became globally extinct during the Holocene, whereas others experienced limited or no significant range change. These findings demonstrate the relatively early onset of prehistoric human impacts on postglacial biodiversity, and mirror species-specific patterns of mammalian extinction during the Late Pleistocene. Herbivores experienced significantly greater declines than carnivores, revealing an important historical extinction filter that informs our understanding of relative resilience and vulnerability to human pressures for different taxa. We highlight the importance of large-scale, long-term datasets for understanding complex protracted extinction processes, although the dynamic pattern of progressive faunal depletion of European mammal assemblages across the Holocene challenges easy identification of ‘static’ past baselines to inform current-day environmental management and restoration.


The Weng'an biota and the Ediacaran radiation of multicellular eukaryotes

Abstract: The rise of multicellularity represents a major evolutionary transition and it occurred independently in multiple eukaryote clades. Although simple multicellular organisms may have evolved in the Mesoproterozoic Era or even earlier, complex multicellular eukaryotes began to diversify only in the Ediacaran Period, just before the Cambrian explosion. Thus, the Ediacaran fossil record can provide key paleontological evidence about the early radiation of multicellular eukaryotes that ultimately culminated in the Cambrian explosion. The Ediacaran Weng'an biota in South China hosts exceptionally preserved eukaryote fossils, including various acanthomorphic acritarchs, pseudoparenchymatous thalli, tubular microfossils, and spheroidal fossils such as Megasphaera , Helicoforamina , Spiralicellula , and Caveasphaera . Many of these fossils have been interpreted as multicellular eukaryotes, although alternative interpretations have also been proposed. In this review, we critically examine these various interpretations, focusing particularly on Megasphaera , which has been variously interpreted as a sulfur-oxidizing bacterium, a unicellular protist, a mesomycetozoean-like holozoan, a volvocine green alga, a stem-group animal, or a crown-group animal. We conclude that Megasphaera is a multicellular eukaryote with evidence for cell-to-cell adhesion, a flexible membrane unconstrained by a rigid cell wall, spatial cellular differentiation, germ-soma separation, and programmed cell death. These features are inconsistent with the bacterium, unicellular protist, and mesomycetozoean-like holozoan interpretations. Thus, the surviving hypotheses, particularly the stem-group animal and algal interpretations, should be further tested with additional evidence. The Weng'an biota also hosts cellularly differentiated pseudoparenchymatous thalli with specialized reproductive structures indicative of an affinity with florideophyte red algae. The other Weng'an fossils reviewed here may also be multicellular eukaryotes, although direct cellular evidence is lacking in some and phylogenetic affinities are poorly constrained in others. The Weng'an biota offers many research opportunities to resolve the life histories and phylogenetic diversity of early multicellular eukaryotes and to illuminate the evolutionary prelude to the Cambrian explosion.

weng'an biota
multicellular eukaryote
alternative interpretation


Primate phylogenomics uncovers multiple rapid radiations and ancient interspecific introgression

Abstract: Our understanding of the evolutionary history of primates is undergoing continual revision due to ongoing genome sequencing efforts. Bolstered by growing fossil evidence, these data have led to increased acceptance of once controversial hypotheses regarding phylogenetic relationships, hybridization and introgression, and the biogeographical history of primate groups. Among these findings is a pattern of recent introgression between species within all major primate groups examined to date, though little is known about introgression deeper in time. To address this and other phylogenetic questions, here, we present new reference genome assemblies for 3 Old World monkey (OWM) species: Colobus angolensis ssp. palliatus (the black and white colobus), Macaca nemestrina (southern pig-tailed macaque), and Mandrillus leucophaeus (the drill). We combine these data with 23 additional primate genomes to estimate both the species tree and individual gene trees using thousands of loci. While our species tree is largely consistent with previous phylogenetic hypotheses, the gene trees reveal high levels of genealogical discordance associated with multiple primate radiations. We use strongly asymmetric patterns of gene tree discordance around specific branches to identify multiple instances of introgression between ancestral primate lineages. In addition, we exploit recent fossil evidence to perform fossil-calibrated molecular dating analyses across the tree. Taken together, our genome-wide data help to resolve multiple contentious sets of relationships among primates, while also providing insight into the biological processes and technical artifacts that led to the disagreements in the first place.

introgression
gene tree discordance
primate


High-level classification of the nautiloid cephalopods: a proposal for the revision of the Treatise Part K

Abstract: High-level classification of the nautiloid cephalopods has been largely neglected since the publication of the Russian and American treatises in the early 1960s. Although there is broad general agreement amongst specialists regarding the status of nautiloid orders, there is no real consensus or consistent approach regarding higher ranks and an array of superorders utilising various morphological features has been proposed. With work now commencing on the revision of the Treatise Part K, there is an urgent need for a methodical and standardised approach to the high-level classification of the nautiloids. The scheme proposed here utilizes the form of muscle attachment scars as a diagnostic feature at subclass level; other features (including siphuncular structures and cameral deposits) are employed at ordinal level. We recognise five subclasses of nautiloid cephalopods (Plectronoceratia, Multiceratia, Tarphyceratia nov., Orthoceratia, Nautilia) and 18 orders including the Order Rioceratida nov. which contains the new family Bactroceratidae. This scheme has the advantage of relative simplicity (it avoids the use of superorders) and presents a balanced approach which reflects the considerable morphological diversity and phylogenetic longevity of the nautiloids in comparison with the ammonoid and coleoid cephalopods. To avoid potential confusion arising in the higher levels of nautiloid classification employed in the revision of the Treatise Part K, we propose herein to replace the suffix '-oidea' at subclass level with the suffix '-ia'. Apart from removing ambiguity and clarifying the nomenclature, this approach also brings greater consistency and affinity with modern zoological classification schemes used for cephalopods. The original Treatise Part K adopted an 'abbreviated' form of name for nautiloid orders using the ending '-cerida' rather than '-ceratida' (e.g., Order Actinocerida rather than Actinoceratida). For the revision of Treatise Part K, we propose using the 'full' version of the ordinal names. This approach re-employs several order names in their original form, e.g., Ellesmeroceratida, Oncoceratida, and Tarphyceratida. For reasons of consistency, we also apply the same to ordinal names created since the original Treatise Part K; therefore, Order Bisonocerida becomes Bisonoceratida.

nautiloid cephalopod
revision
high-level classification


Preservation potential of keratin in deep time

Abstract: Multiple fossil discoveries and taphonomic experiments have established the durability of keratin. The utility and specificity of antibodies to identify keratin peptides has also been established, both in extant feathers under varying treatment conditions, and in feathers from extinct organisms. Here, we show localization of feather-keratin antibodies to control and heat-treated feathers, testifying to the repeatability of initial data supporting the preservation potential of keratin. We then show new data at higher resolution that demonstrates the specific response of these antibodies to the feather matrix, we support the presence of protein in heat-treated feathers using ToF-SIMS, and we apply these methods to a fossil feather preserved in the unusual environment of sinter hot springs. We stress the importance of employing realistic conditions such as sediment burial when designing experiments intended as proxies for taphonomic processes occurring in the fossil record. Our data support the hypothesis that keratin, particularly the β-keratin that comprises feathers, has potential to preserve in fossil remains.

keratin
environment
preservation potential


Ancient amino acids from fossil feathers in amber

Abstract: Ancient protein analysis is a rapidly developing field of research. Proteins ranging in age from the Quaternary to Jurassic are being used to answer questions about phylogeny, evolution, and extinction. However, these analyses are sometimes contentious, and focus primarily on large vertebrates in sedimentary fossilisation environments; there are few studies of protein preservation in fossils in amber. Here we show exceptionally slow racemisation rates during thermal degradation experiments of resin enclosed feathers, relative to previous thermal degradation experiments of ostrich eggshell, coral skeleton, and limpet shell. We also recover amino acids from two specimens of fossil feathers in amber. The amino acid compositions are broadly similar to those of degraded feathers, but concentrations are very low, suggesting that much of the original protein has been degraded and lost. High levels of racemisation in more apolar, slowly racemising amino acids suggest that some of the amino acids were ancient and therefore original. Our findings indicate that the unique fossilisation environment inside amber shows potential for the recovery of ancient amino acids and proteins.


Decimetre-scale multicellular eukaryotes from the 1.56-billion-year-old Gaoyuzhuang Formation in North China

Abstract: Fossils of macroscopic eukaryotes are rarely older than the Ediacaran Period (635–541 million years (Myr)), and their interpretation remains controversial. Here, we report the discovery of macroscopic fossils from the 1,560-Myr-old Gaoyuzhuang Formation, Yanshan area, North China, that exhibit both large size and regular morphology. Preserved as carbonaceous compressions, the Gaoyuzhuang fossils have statistically regular linear to lanceolate shapes up to 30 cm long and nearly 8 cm wide, suggesting that the Gaoyuzhuang fossils record benthic multicellular eukaryotes of unprecedentedly large size. Syngenetic fragments showing closely packed ∼10 μm cells arranged in a thick sheet further reinforce the interpretation. Comparisons with living thalloid organisms suggest that these organisms were photosynthetic, although their phylogenetic placement within the Eukarya remains uncertain. The new fossils provide the strongest evidence yet that multicellular eukaryotes with decimetric dimensions and a regular developmental program populated the marine biosphere at least a billion years before the Cambrian Explosion.

multicellular eukaryote
gaoyuzhuang formation
north china


Simple versus complex models of trait evolution and stasis as a response to environmental change

Abstract: Significance Paleontologists have long argued about what the fossil record call tell us about how species evolve over long periods. Simple models such as stasis and random walks have been used to explore evolutionary patterns, but these have not always adequately captured the ways in which traits change over time in fossil species. Here we find that models with complex evolutionary dynamics are often favored, especially for fossil series that sample many populations, suggesting that the underlying evolutionary reality is likely more complex than represented by simplified—though still useful—models of trait change. Previous analyses of evolutionary patterns, or modes, in fossil lineages have focused overwhelmingly on three simple models: stasis, random walks, and directional evolution. Here we use likelihood methods to fit an expanded set of evolutionary models to a large compilation of ancestor–descendant series of populations from the fossil record. In addition to the standard three models, we assess more complex models with punctuations and shifts from one evolutionary mode to another. As in previous studies, we find that stasis is common in the fossil record, as is a strict version of stasis that entails no real evolutionary changes. Incidence of directional evolution is relatively low (13%), but higher than in previous studies because our analytical approach can more sensitively detect noisy trends. Complex evolutionary models are often favored, overwhelmingly so for sequences comprising many samples. This finding is consistent with evolutionary dynamics that are, in reality, more complex than any of the models we consider. Furthermore, the timing of shifts in evolutionary dynamics varies among traits measured from the same series. Finally, we use our empirical collection of evolutionary sequences and a long and highly resolved proxy for global climate to inform simulations in which traits adaptively track temperature changes over time. When realistically calibrated, we find that this simple model can reproduce important aspects of our paleontological results. We conclude that observed paleontological patterns, including the prevalence of stasis, need not be inconsistent with adaptive evolution, even in the face of unstable physical environments.


Theropod teeth from the Judith River Formation (Upper Cretaceous) of south-central Montana

Abstract: Theropod teeth are some of the most diagnostic fossils from dinosaur assemblages, with taxonomic utility to the genus or even species level. One hundred and twenty-nine teeth, representing five theropod taxa, have been recovered from eight localities along a 75 km east-west transect in the Judith River Formation of south-central Montana. Unlike the pattern of distribution observed for the Judith River Formation in Alberta, no geographic or temporal differentiation of the theropod faunas seems to have occurred in this formation in south-central Montana.

judith river formation
south-central montana
theropod tooth


The evolution of locomotor stamina in tetrapods: circumventing a mechanical constraint

Abstract: Endothermic tetrapods differ dramatically from ectothermic tetrapods in having a great capacity to sustain vigorous locomotion. I suggest that this difference reflects alternative adaptive responses to a mechanical constraint that was an inherent consequence of the vertebrate transition from aquatic to terrestrial modes of locomotion and respiration. The earliest tetrapods may not have been able to walk and breathe at the same time. Their sprawling gait and lateral vertebral bending would have required unilateral contractions of the thoracic musculature that may have interfered with the bilateral movements necessary for breathing. Modern lizards, whose locomotor and respiratory anatomy resembles that of the early tetrapods, provide support for this hypothesis because their breathing is greatly reduced during locomotor activity. Tetrapod lineages that gave rise to modern ectotherms apparently retained the constraint, becoming either highly specialized for burst activity based on anaerobic metabolism or specialized in passive mechanisms of defense against predators. The lineages from which birds and mammals are derived have undergone morphological changes that enable simultaneous running and breathing. In modern tetrapods upright posture is correlated with endothermic metabolism. This correlation may have arisen to circumvent ancestral constraints on locomotor stamina.

locomotor stamina
tetrapod
mechanical constraint
upright posture


Squamates from the Jurassic and Cretaceous of North America

Abstract: Squamates from the Mesozoic of North America have been collected since the end of the nineteenth century. To date, the fossils are known to occur in the Late Jurassic, Aptian-Albian, Cenomanian, Turonian, Santonian, Campanian, and Maastrichtian. Most of the records are from the Western Interior in the arid regions associated with the Rocky Mountains. Geographically, these records extend from central Alberta, Canada, south to northern Mexico. The earliest squamates are primitive forms of scincoideans and anguimorphans from the Late Jurassic-Early Cretaceous. At the beginning of the Late Cretaceous, the squamate fauna in North America changes dramatically to include a much greater diversity of taxa with a mix of lineages now extinct (e.g. Polyglyphanodontini, Chamopsiidae, Contogeniidae) and lineages still alive today (e.g. Anguidae, Xantusiidae, Platynota, Serpentes). The greatest diversity appears to be during the late Campanian, but diversity appears correlated with number of localities sampled and the late Campanian is the best sampled horizon in the Mesozoic of North America. The apparent sudden change in the North American squamate fauna is coincident with similar changes to other vertebrates (mammals, dinosaurs) and the opening of a land bridge with Asia. The lack of taxonomic and systematic study of the squamates from the Early Cretaceous of Asia makes comparison difficult, but it is likely that introduction of Asian taxa into North America was responsible, at least in part, for the relatively rapid change in the North American fauna. The hypotheses of an additional invasion from Asia during the Turonian is not supported, but the hypothesis of a second opening with Asia during the Santonian is weakly supported by the appearance of an iguanian in North America. Additional iguanians from the Campanian may have evolved in situ or may have entered North America from Asia as late as the mid-Campanian. Many of the most conspicuous lizards of the Late Cretaceous (Polyglyphanodontini, Chamopsiidae, paramacellodid-cordylid grade scincoideans) went extinct at the terminal Cretaceous extinction event, while most of the anguimorphans and snakes appear little affected. Amphisbaenians do not appear in North America until after the early Paleocene.


A new large mammal from the Ypresian of Morocco: Evidence of surprising diversity of early proboscideans

Abstract: We describe a new primitive proboscidean, Daouitherium rebouli gen. et sp. nov., from the early Ypresian of the Ouled Abdoun Basin, Morocco, which also yielded Phosphatherium. It is the earliest known large mammal from Africa and one of the oldest known proboscideans. It has true lophodont molars similar to those of Barytherium and Numidotherium. It is closer to these genera and more advanced than Phosphatherium (e.g., morphology of the mandible), but it is also primitive in striking features known also in Phosphatherium (absence of diastema, retention of two additional teeth in front of p2). A parsimony analysis of Daouitherium suggests its intermediate phylogenetic position between the basal, small Phosphatherium and the large, more derived Numidotherium and Barytherium. Daouitherium is a better candidate for the ancestry of N. koholense than Phosphatherium, but it is also specialized. Daouitherium and Numidotherium may belong to the same basal radiation of "Barytherioidea". However, the family referral of Daouitherium is uncertain (Numidotheriidae?). The discovery of such a large and derived proboscidean with respect to Phosphatherium in the same African beds of such antiquity is evidence of an unexpected early diversity of proboscideans and of the old origin of the order. It also supports the African origin of Proboscidea s.s.


First African thylacocephalans from the Famennian of Morocco and their role in Late Devonian food webs

Abstract: Thylacocephalans are enigmatic arthropods with an erratic Palaeozoic and Mesozoic fossil record. In many of the few localities where they occur, they are quite abundant. This also holds true for the Famennian Thylacocephalan Layer in the Maider (eastern Anti-Atlas of Morocco), a small epicontinental basin hosting some strata with taphonomic properties of a conservation deposit yielding exceptionally preserved gnathostomes and non-vertebrates. In a thin argillaceous interval in the earliest middle Famennian, thylacocephalans occur in such great numbers that they became eponyms of this unit. Therein, we discovered a new taxon of thylacocephalans, Concavicaris submarinus sp. nov., which represent the oldest records of thylacocephalans from Africa. In the CT-imagery, the holotype of Concavicaris submarinus sp. nov. revealed anatomical details including its eyes, appendages and other soft parts. Sedimentary facies and faunal composition of the Thylacocephalan Layer suggest that these animals populated the water column above the low-oxygen sea floor. Thus, thylacocephalans likely represented an important component of the diet of chondrichthyans and placoderms, which are quite common as well. The abundance of thylacocephalans in other conservation deposits like the Cleveland Shale (USA) and the Gogo Formation (Australia) underline their pivotal role in Late Devonian pelagic food webs.


Traces of the bone-eating annelid Osedax in Oligocene whale teeth and fish bones

Abstract: The range of substrates that the bone-eating marine worm Osedax is able to consume has important implications for its evolutionary history, especially its potential link to the rise of whales. Once considered a whale specialist, recent work indicates that Osedax consumes a wide range of vertebrate remains, including whale soft tissue and the bones of mammals, birds and fishes. Traces resembling those produced by living Osedax have now been recognized for the first time in Oligocene whale teeth and fish bones from deep-water strata of the Makah, Pysht and Lincoln Creek formations in western Washington State, USA. The specimens were acid etched from concretions, and details of the borehole morphology were investigated using micro-computed tomography. Together with previously published Osedax traces from this area, our results show that by Oligocene time Osedax was able to colonize the same range of vertebrate remains that it consumes today and had a similar diversity of root morphologies. This supports the view that a generalist ability to exploit vertebrate bones may be an ancestral trait of Osedax.


The oldest known bryozoan: Prophyllodictya (Cryptostomata) from the lower Tremadocian (Lower Ordovician) of Liujiachang, south‐western Hubei, central China

Abstract: A new cryptostome bryozoan, Prophyllodictya simplex sp. nov., is described from the Nantzinkuan Formation (Lower Ordovician, lower Tremadoc) of Liujiachang, central China. This antedates the previously oldest known bryozoan by several million years. Colony morphology and the phylogenetic position of Prophyllodictya within Cryptostomata are explored. Phylogenetic analysis suggests that Cryptostomata (except Prophyllodictya) can be divided into two major groups, and that Prophyllodictya occupies a basal position in the cryptostome tree, which accords with its simple morphology and antiquity. A close relationship is evident between bryozoans from the South China palaeoplate and those from Baltica.

bryozoan
cryptostomata
lower ordovician
taxonomic diversity
biotope


Beyond the print—virtual paleontology in science publishing, outreach, and education

Abstract: Abstract Virtual paleontology unites a variety of computational techniques and methods for the visualization and analysis of fossils. Due to their great potential and increasing availability, these methods have become immensely popular in the last decade. However, communicating the wealth of digital information and results produced by the various techniques is still exacerbated by traditional methods of publication. Transferring and processing three-dimensional information, such as interactive models or animations, into scientific publications still poses a challenge. Here, we present different methods and applications to communicate digital data in academia, outreach and education. Three-dimensional PDFs, QR codes, anaglyph stereo imaging, and rapid prototyping—methods routinely used in the engineering, entertainment, or medical industries—are outlined and evaluated for their potential in science publishing and public engagement. Although limitations remain, these are simple, mostly cost-effective, and powerful tools to create novel and innovative resources for education, public engagement, or outreach.


The evolution of the giant deer, Megaloceros giganteus (Blumenbach)

Abstract: Abstract The giant deer, Megaloceros giganteus , is best known from its fossil occurrences in Ireland around 11 000 years ago, but has a history across Europe and Western Asia spanning 300 000-400 000 years. This paper reports a biometric study of variation and evolution in the giant deer through its history. Most early populations were as large in body size as the Irish sample, but some were distinctly smaller and others had markedly shorter limbs. Thickened skull and mandibular bones, especially marked in males, are constant throughout the species' history. Some earlier populations had antlers which were relatively smaller, more upright and differing in other details from the celebrated Irish specimens. Observed variation in body and antler form is discussed in terms of changing palaeoenvironments. Interpretation of the fighting or display roles of M. giganteus antlers needs to take account of their differing forms through time.

giant deer
megaloceros giganteus
blumenbach


Biotic replacement and mass extinction of the Ediacara biota

Abstract: The latest Neoproterozoic extinction of the Ediacara biota has been variously attributed to catastrophic removal by perturbations to global geochemical cycles, ‘biotic replacement’ by Cambrian-type ecosystem engineers, and a taphonomic artefact. We perform the first critical test of the ‘biotic replacement’ hypothesis using combined palaeoecological and geochemical data collected from the youngest Ediacaran strata in southern Namibia. We find that, even after accounting for a variety of potential sampling and taphonomic biases, the Ediacaran assemblage preserved at Farm Swartpunt has significantly lower genus richness than older assemblages. Geochemical and sedimentological analyses confirm an oxygenated and non-restricted palaeoenvironment for fossil-bearing sediments, thus suggesting that oxygen stress and/or hypersalinity are unlikely to be responsible for the low diversity of communities preserved at Swartpunt. These combined analyses suggest depauperate communities characterized the latest Ediacaran and provide the first quantitative support for the biotic replacement model for the end of the Ediacara biota. Although more sites (especially those recording different palaeoenvironments) are undoubtedly needed, this study provides the first quantitative palaeoecological evidence to suggest that evolutionary innovation, ecosystem engineering and biological interactions may have ultimately caused the first mass extinction of complex life.

mass extinction
ediacara biota
complex life


Caudal autotomy as anti-predatory behaviour in Palaeozoic reptiles

Abstract: Many lizards can drop a portion of their tail in response to an attack by a predator, a behaviour known as caudal autotomy. The capacity for intravertebral autotomy among modern reptiles suggests that it evolved in the lepidosaur branch of reptilian evolution, because no such vertebral features are known in turtles or crocodilians. Here we present the first detailed evidence of the oldest known case of caudal autotomy, found only among members of the Early Permian captorhinids, a group of ancient reptiles that diversified extensively and gained a near global distribution before the end-Permian mass extinction event of the Palaeozoic. Histological and SEM evidence show that these early reptiles were the first amniotes that could autotomize their tails, likely as an anti-predatory behaviour. As in modern iguanid lizards, smaller captorhinids were able to drop their tails as juveniles, presumably as a mechanism to evade a predator, whereas larger individuals may have gradually lost this ability. Caudal autotomy in captorhinid reptiles highlights the antiquity of this anti-predator behaviour in a small member of a terrestrial community composed predominantly of larger amphibian and synapsid predators.

anti-predatory behaviour
captorhinid
caudal autotomy


Abstract: Shu Li, Ying Wang, Dong Ren, & Hong Pang, December 2012. Revision of the genus Sunotettigarcta Hong, 1983 (Hemiptera, Tettigarctidae), with a new species from Daohugou, Inner Mongolia, China. Alcheringa 36, 501–507. ISSN 0311–5518. A new species of fossil Tettigarctidae Sunotettigarcta hirsuta Li, Wang & Ren sp. nov., is described based on a nearly complete female specimen from the Middle Jurassic of Daohugou, Inner Mongolia, northeastern China. The diagnosis of Sunotettigarcta Hong, 1983 is emended.

genus sunotettigarcta hong
hemiptera
tettigarctidae


Divaricate growth habit in Williamsoniaceae (Bennettitales): unravelling the ecology of a key Mesozoic plant group

Abstract: Representatives of Williamsoniacae (Bennettitales) are usually restored as small-leafed shrubs or low-growing trees with densely interlaced stems bifurcating or trifurcating at broad angles-a growth form referred to as divaricating. A divaricate plant architecture has evolved independently in at least 18 modern plant families, of which the majority occur in New Zealand, where they constitute more than 10 % of the flora. Botanists favour two or three hypotheses on the benefits of a divaricating habit for modern plants. One hypothesis favours the evolution of this habit to protect the foliage and reproductive structures from browsing by large mammals or large flightless birds, such as the recently extinct moa or other ratites. Another argues that this habit evolved in response to a dry, windy or frosty climate, whereas a third regards divarication as having evolved to optimise foliar light harvesting. Our evaluation of these hypotheses with respect to the ecological pressures known to have been experienced by Williamsoniaceae in the mid-Mesozoic reveals that although defence against browsing tetrapods cannot be excluded as a selective pressure that promoted divarication in Williamsoniaceae, many of the anatomical and morphological features of this family appear to represent responses to local environmental conditions. In this context, representatives of Williamsoniaceae have many characters that are convergent with members of Banksiinae (Proteaceae), suggesting adaptation to open vegetation communities on nutrient-deficient soils.

williamsoniaceae
bennettitales
plant group


Checklist and Scoring System for the Assessment of Soft Tissue Preservation in CT Examinations of Human Mummies

Abstract: The purpose of this study was to develop a checklist for standardized assessment of soft tissue preservation in human mummies based on whole-body computed tomography examinations, and to add a scoring system to facilitate quantitative comparison of mummies. Computed tomography examinations of 23 mummies from the Capuchin Catacombs of Palermo, Sicily (17 adults, 6 children; 17 anthropogenically and 6 naturally mummified) and 7 mummies from the crypt of the Dominican Church of the Holy Spirit of Vilnius, Lithuania (5 adults, 2 children; all naturally mummified) were used to develop the checklist following previously published guidelines. The scoring system was developed by assigning equal scores for checkpoints with equivalent quality. The checklist was evaluated by intra- and inter-observer reliability. The finalized checklist was applied to compare the groups of anthropogenically and naturally mummified bodies. The finalized checklist contains 97 checkpoints and was divided into two main categories, “A. Soft Tissues of Head and Musculoskeletal System” and “B. Organs and Organ Systems”, each including various subcategories. The complete checklist had an intra-observer reliability of 98% and an inter-observer reliability of 93%. Statistical comparison revealed significantly higher values in anthropogenically compared to naturally mummified bodies for the total score and for three subcategories. In conclusion, the developed checklist allows for a standardized assessment and documentation of soft tissue preservation in whole-body computed tomography examinations of human mummies. The scoring system facilitates a quantitative comparison of the soft tissue preservation status between single mummies or mummy collections.

scoring system
soft tissue preservation
human mummies


Identifying patterns and drivers of coral diversity in the Central Indo-Pacific marine biodiversity hotspot

Abstract: Abstract. Biodiversity hotspots are increasingly recognized as areas of high taxonomic and functional diversity. These hotspots are dynamic and shift geographically over time in response to environmental change. To identify drivers of the origin, evolution, and persistence of diversity hotspots,we investigated the diversity patterns of reef-building corals (Scleractinia) in the Central Indo-Pacific, a marine biodiversity hotspot for the last 25 Myr. We used the scleractinian fossil record (based on literature and a newly acquired fossil collection) to examine the taxonomic and functional diversity of corals from the Eocene to Pliocene. Our data identify potential drivers of coral diversity through time (and space) in the Central Indo-Pacific by constraining the timing of taxonomic turnover events and correlating them with known environmental changes. Increases in taxonomic diversity, high origination rates, and changes in abundance of functional character states indicate that the origin of the Central Indo-Pacific hotspot occurred during the Oligocene, initially through proliferation of pre-existing taxa and then by origination of new taxa. In contrast to taxonomic diversity, overall functional diversity of Central Indo-Pacific reef-building corals remained constant from the Eocene to the Pliocene. Our results identify global sea level as a main driver of diversity increase that, together with local tectonics, regulates availability of suitable habitats. Moreover, marine biodiversity hotspots develop from both the accumulation of taxa from older biodiversity hotspots and origination of new taxa. Our study demonstrates the utility of a combined literature-based and new collection approach for gaining new insights into the timing, drivers, and development of tropical biodiversity hotspots.

coral
central indo-pacific
marine biodiversity hotspot


Disparities in correlating microstructural to nanostructural preservation of dinosaur femoral bones

Abstract: Osteohistological researches on dinosaurs are well documented, but descriptions of direct correlations between the bone microstructure and corresponding nanostructure are currently lacking. By applying correlative microscopy, we aimed to verify that well-preserved osteohistological features correlate with pristine fossil bone nanostructures from the femoral bones of Koreanosaurus boseongensis. The quality of nanostructural preservation was evaluated based on the preferred orientation level of apatite crystals obtained from selected area electron diffraction (SAED) patterns and by measuring the “arcs” from the {100} and {002} diffraction rings. Unlike our expectations, our results revealed that well-preserved microstructures do not guarantee pristine nanostructures and vice versa. Structural preservation of bone from macro- to nanoscale primarily depends on original bioapatite density, and subsequent taphonomical factors such as effects from burial, pressure, influx of external elements and the rate of diagenetic alteration of apatite crystals. Our findings suggest that the efficient application of SAED analysis opens the opportunity for comprehensive nanostructural investigations of bone.

nanostructural preservation
femoral bone
osteohistological feature


An ammonite trapped in Burmese amber

Abstract: Significance Aquatic organisms are rarely found in amber, but when they occur they provide invaluable evidence for the better understanding of amber taphonomy and past ecosystems. We report an ammonite and several marine gastropods alongside a mixed assemblage of intertidal and terrestrial forest floor organisms in mid-Cretaceous Burmese amber. Our discovery indicates that the Burmese amber forest was living near a dynamic and shifting coastal environment. The ammonite also provides supporting evidence for the age of the amber, which is still debated, and represents a rare example of dating using fossils present inside the amber. Amber is fossilized tree resin, and inclusions usually comprise terrestrial and, rarely, aquatic organisms. Marine fossils are extremely rare in Cretaceous and Cenozoic ambers. Here, we report a record of an ammonite with marine gastropods, intertidal isopods, and diverse terrestrial arthropods as syninclusions in mid-Cretaceous Burmese amber. We used X-ray–microcomputed tomography (CT) to obtain high-resolution 3D images of the ammonite, including its sutures, which are diagnostically important for ammonites. The ammonite is a juvenile Puzosia (Bhimaites) and provides supporting evidence for a Late Albian–Early Cenomanian age of the amber. There is a diverse assemblage (at least 40 individuals) of arthropods in this amber sample from both terrestrial and marine habitats, including Isopoda, Acari (mites), Araneae (spiders), Diplopoda (millipedes), and representatives of the insect orders Blattodea (cockroaches), Coleoptera (beetles), Diptera (true flies), and Hymenoptera (wasps). The incomplete preservation and lack of soft body of the ammonite and marine gastropods suggest that they were dead and underwent abrasion on the seashore before entombment. It is most likely that the resin fell to the beach from coastal trees, picking up terrestrial arthropods and beach shells and, exceptionally, surviving the high-energy beach environment to be preserved as amber. Our findings not only represent a record of an ammonite in amber but also provide insights into the taphonomy of amber and the paleoecology of Cretaceous amber forests.


Ontogenetic trajectories of septal spacing and conch shape in the Late Cretaceous gaudryceratid ammonoids: implications for their post‐embryonic palaeoecology

Abstract: In this study, we analysed the ontogenetic trajectories of septal spacing between succeeding chambers of the gaudryceratid ammonoid, Gaudryceras tenuiliratum, which were collected in the Tomamae and Mikasa areas of Hokkaido, Japan. The ontogenetic trajectories of septal spacing in G. tenuiliratum demonstrate a general trend: two cycles of increasing to decreasing septal spacing until about the 30th septum, gradually decreasing septal spacing until about the 70th septum, and then gradually increasing septal spacing at least until about the 110th septum. The ontogenetic trajectories of the whorl expansion rate (WER) in our specimens also demonstrated that a decreasing trend changed into an increasing trend at a conch diameter of c. 5–7 mm. This conch diameter corresponds to the end of the second cycle of increasing to decreasing septal spacing occurring before about the 30th septum, at which point G. tenuiliratum possibly transitioned from planktic to nektobenthic habits. No significant differences were detected in the ontogenetic trajectories of septal spacing and conch shape between the two areas, which implies that the ontogenetic trajectory patterns of septal spacing in the Late Cretaceous ammonoids were taxonomy‐dependent rather than environment‐dependent, although this should be further examined with G. tenuiliratum collected from areas outside of Hokkaido.

septal spacing
gaudryceratid ammonoid
ontogenetic trajectory


Exploring uncertainty in the calibration of the molecular clock

Abstract: Calibration is a critical step in every molecular clock analysis but it has been the least considered. Bayesian approaches to divergence time estimation make it possible to incorporate the uncertainty in the degree to which fossil evidence approximates the true time of divergence. We explored the impact of different approaches in expressing this relationship, using arthropod phylogeny as an example for which we established novel calibrations. We demonstrate that the parameters distinguishing calibration densities have a major impact upon the prior and posterior of the divergence times, and it is critically important that users evaluate the joint prior distribution of divergence times used by their dating programmes. We illustrate a procedure for deriving calibration densities in Bayesian divergence dating through the use of soft maximum constraints.

calibration
molecular clock
divergence time estimation
prior distribution
fossil calibration


Early Cambrian fuxianhuiids from China reveal origin of the gnathobasic protopodite in euarthropods

Abstract: Euarthropods owe their evolutionary and ecological success to the morphological plasticity of their appendages. Although this variability is partly expressed in the specialization of the protopodite for a feeding function in the post-deutocerebral limbs, the origin of the former structure among Cambrian representatives remains uncertain. Here, we describe Alacaris mirabilis gen. et sp. nov. from the early Cambrian Xiaoshiba Lagerstätte in China, which reveals the proximal organization of fuxianhuiid appendages in exceptional detail. Proximally, the post-deutocerebral limbs possess an antero-posteriorly compressed protopodite with robust spines. The protopodite is attached to an endopod with more than a dozen podomeres, and an oval flap-shaped exopod. The gnathal edges of the protopodites form an axial food groove along the ventral side of the body, indicating a predatory/scavenging autecology. A cladistic analysis indicates that the fuxianhuiid protopodite represents the phylogenetically earliest occurrence of substantial proximal differentiation within stem-group Euarthropoda illuminating the origin of gnathobasic feeding.

china
gnathobasic protopodite
euarthropod


Dinosaur incubation periods directly determined from growth-line counts in embryonic teeth show reptilian-grade development

Abstract: Significance Little is known regarding nonavian dinosaur embryology. Embryological period relates to myriad aspects of development, life history, and evolution. In reptiles incubation is slow, whereas in birds it is remarkably rapid. Because birds are living dinosaurs, rapid incubation has been assumed for all dinosaurs. We discovered daily forming growth lines in teeth of embryonic nonavian dinosaurs revealing incubation times. These lines show slow reptilian-grade development spanning months. The rapid avian condition likely evolved within birds prior to the Cretaceous–Paleogene (K–Pg) mass extinction event. Prolonged incubation exposed nonavian dinosaur eggs and attending parents to destructive influences for long periods. Slow development may have affected their ability to compete with more rapidly generating populations of birds, reptiles, and mammals following the K–Pg cataclysm. Birds stand out from other egg-laying amniotes by producing relatively small numbers of large eggs with very short incubation periods (average 11–85 d). This aspect promotes high survivorship by limiting exposure to predation and environmental perturbation, allows for larger more fit young, and facilitates rapid attainment of adult size. Birds are living dinosaurs; their rapid development has been considered to reflect the primitive dinosaurian condition. Here, nonavian dinosaurian incubation periods in both small and large ornithischian taxa are empirically determined through growth-line counts in embryonic teeth. Our results show unexpectedly slow incubation (2.8 and 5.8 mo) like those of outgroup reptiles. Developmental and physiological constraints would have rendered tooth formation and incubation inherently slow in other dinosaur lineages and basal birds. The capacity to determine incubation periods in extinct egg-laying amniotes has implications for dinosaurian embryology, life history strategies, and survivorship across the Cretaceous–Paleogene mass extinction event.

incubation period
growth-line count
reptilian-grade development
egg
embryonic tooth


Response of the ITCZ to Northern Hemisphere cooling

Abstract: Climate simulations, using models with different levels of complexity, indicate that the north‐south position of the intertropical convergence zone (ITCZ) responds to changes in interhemispheric temperature contrast. Paleoclimate data on a variety of timescales suggest a similar behavior, with southward displacements of the ITCZ and associated changes in tropical atmospheric circulation during cold periods in the Northern Hemisphere. To identify a mechanism by which ITCZ displacements can be forced from the extratropics, we use a climate model with idealized geography and a simple slab ocean. We cool the northern extratropics and warm the southern extratropics to represent the asymmetric temperature changes associated with glacial‐interglacial and millennial‐scale climate variability. A southward shift in the ITCZ occurs, along with changes in the trade winds and an asymmetric response of the Hadley circulation. Changes in atmospheric heat exchange between the tropics and midlatitudes are the likely cause of this response, suggesting that this mechanism may play an important role in ITCZ displacements on timescales from decadal to glacial‐interglacial.

itcz
northern hemisphere
intertropical convergence zone


Coupling of palaeontological and neontological reef coral data improves forecasts of biodiversity responses under global climatic change

Abstract: Reef corals are currently undergoing climatically driven poleward range expansions, with some evidence for equatorial range retractions. Predicting their response to future climate scenarios is critical to their conservation, but ecological models are based only on short-term observations. The fossil record provides the only empirical evidence for the long-term response of organisms under perturbed climate states. The palaeontological record from the Last Interglacial (LIG; 125 000 years ago), a time of global warming, suggests that reef corals experienced poleward range shifts and an equatorial decline relative to their modern distribution. However, this record is spatio-temporally biased, and existing methods cannot account for data absence. Here, we use ecological niche modelling to estimate reef corals' realized niche and LIG distribution, based on modern and fossil occurrences. We then make inferences about modelled habitability under two future climate change scenarios (RCP4.5 and RCP8.5). Reef coral ranges during the LIG were comparable to the present, with no prominent equatorial decrease in habitability. Reef corals are likely to experience poleward range expansion and large equatorial declines under RCP4.5 and RCP8.5. However, this range expansion is probably optimistic in the face of anthropogenic climate change. Incorporation of fossil data in niche models improves forecasts of biodiversity responses under global climatic change.

forecast
biodiversity response
climatic change


Endemicity and palaeobiogeography of the Osteostraci and Galeaspida: a test of scenarios of gnathostome evolution

Abstract: Abstract:  Armoured stem‐gnathostomes (jawless vertebrates previously termed ‘ostracoderms’) have long been assumed to exhibit strong endemicity. This assumption has underpinned their utility in many palaeobiogeographic studies as well as scenarios regarding the evolution and dominance of jawed vertebrates over their jawless relatives. The hypothesis of endemicity in stem‐gnathostomes is investigated for the first time in the light of the phylogeny of the closest relatives of jawed vertebrates – Osteostraci and Galeaspida. Palaeobiogeography of each is reconstructed using Fitch optimization and modified Brooks Parsimony Analysis. Palaeobiogeographic distributions corroborate phylogeny. Results, along with consideration of the Heterostraci, enable identification of similar patterns across groups (broad ancestral range, Early Devonian expansion, endemic and pandemic clades within each, and Middle Devonian radiation events) and inferences to the palaeogeographic relationship between major terranes (i.e. Laurentia, Baltica, Avalonia, Kara, Altaids, South China, Tarim). Comparison of basin and terrane level analyses identifies the different palaeogeographic processes responsible for the distributions of each group: sea‐level changes in the case of the Osteostraci and rifting in the case of the Galeaspida. The general endemic nature of the Osteostraci and Galeaspida is confirmed, and thus the hypothesis that the demise and extinction of stem‐gnathostomes was because of their limited dispersal capacity is supported.


UV-B absorbing compounds in present-day and fossil pollen, spores, cuticles, seed coats and wood: evaluation of a proxy for solar UV radiation

Abstract: UV-B absorbing compounds (UACs) in present-day and fossil pollen, spores, cuticles, seed coats and wood have been evaluated as a proxy for past UV. This proxy may not only provide information on variation of stratospheric ozone and solar UV in the period preceding and during the Antarctic ozone hole (1974–present day), but also on the development and variation of the stratospheric ozone layer and solar surface UV during the evolution of life on Earth. Sporopollenin and cutin are highly resistant biopolymers, preserving well in the geological record and contain the phenolic acids p -coumaric ( p CA) and ferulic acid (FA). p CA and FA represent a good perspective for a plant-based proxy for past surface UV radiation since they are induced by solar UV-B via the phenylpropanoid pathway (PPP). UV-B absorption by these monomers in the wall of pollen and spores and in cuticles may prevent damage to the cellular metabolism. Increased p CAand FA in pollen of Vicia faba exposed to enhanced UV-B was found in greenhouse experiments. Further correlative evidence comes from UV-absorbing compounds in spores from 1960–2000 comparing exposure of land plants ( Lycopodium species) to solar UV before and during ozone depletion and comparing plants from Antarctica (severe ozone depletion), Arctic, and other latitudes with less or negligible ozone depletion. Wood-derived compounds guaiacyl (G), syringyl (S), and p -hydroxyphenyl (P) are produced via the PPP. The proportions of P, G, and S in the lignin differ between various plant groups ( e.g. dicotyledons/monocotyledons, gymnosperms/ angiosperms). It is hypothesized that this lignin composition and derived physiological and physical properties of lignin (such as tree-ring wood density) has potential as a proxy for palaeo-UV climate. However validation by exposure of trees to enhanced UV is lacking. p CAand FA also form part of cutin polymers and are found in extant and fossil Ginkgo leaf cuticles as shown by thermally-assisted hydrolysis and methylation (THM)-pyrolysis-GC-MS. Potentially, the time scale for reconstruction of ozone column thickness and UV-B based on the UAC UV proxy may be decadal, centennial, millennial and possibly billenial. For further development of the UACs and p CA and FA-based UV proxy, it is necessary to obtain the UV dose–response (content of UACs, p CA and FA in sporopollenin and cutin) relationships for validation, based on outdoor UV radiation manipulations experiments with plants, and comparative analysis of stored plants (herbaria) or fossil material of the same or related plant species.


Accurate estimation of sea surface temperatures using dissolution‐corrected calibrations for Mg/Ca paleothermometry

Abstract: [1] Paired δ18O and Mg/Ca measurements on the same foraminiferal shells offer the ability to independently estimate sea surface temperature (SST) changes and assess their temporal relationship to the growth and decay of continental ice sheets. The accuracy of this method is confounded, however, by the absence of a quantitative method to correct Mg/Ca records for alteration by dissolution. Here we describe dissolution-corrected calibrations for Mg/Ca-paleothermometry in which the preexponent constant is a function of size-normalized shell weight: (1) for G. ruber (212–300 μm) (Mg/Ca)ruber = (0.025 wt + 0.11) e0.095T and (b) for G. sacculifer (355–425 μm) (Mg/Ca)sacc = (0.0032 wt + 0.181) e0.095T. The new calibrations improve the accuracy of SST estimates and are globally applicable. With this correction, eastern equatorial Atlantic SST during the Last Glacial Maximum is estimated to be 2.9° ± 0.4°C colder than today.


The Putative Cardiomyines (Rodentia, Cavioidea) of the Middle Miocene of Patagonia (Argentina) and the Differentiation of the Family Hydrochoeridae

Abstract: The putative cardiomyines (Rodentia, Cavioidea) of the middle Miocene of Patagonia (Argentina) and the differentiation of the Family Hydrochoeridae Maria G. Vucetich a & Maria E. Perez a b a Departamento Cientifico Paleontologia de Vertebrados, Museo de La Plata, Paseo del Bosque s/n B1900FWA, La Plata, Buenos Aires, Argentina b Museo Paleontologico “Egidio Feruglio,” Av. Fontana Nro. 140, U9100GYO, Trelew, Chubut, Argentina


The first pre‐Quaternary fossil record of the clade Mabuyidae with a comment on the enclosure of the Meckelian canal in skinks

Abstract: We here describe the first Neogene record of the squamate clade Mabuyidae. Although this clade has a cosmopolitan distribution today, no pre‐Quaternary fossil record of these reptiles has so far been documented. The material comes from the locality Solnechnodolsk (Russia) and is dated to the late Miocene (MN 13). Although it comprises only jaw elements, it constitutes the first evidence of the occurrence of fossil skinks around the area of the Black Sea. The material is identical to Heremites vittatus, showing the existence of this lineage as early as the late Miocene. Thus, it may be used as a potential calibration point for further studies. The comparative anatomy of the structures of lower jaw in selected scincomorph taxa with a special reference to Mabuya group is presented. The closure of the Meckelian canal is the condition at the basal node of the clade Sphenomorphidae + Eugongylidae + Egerniidae + Mabuyidea, whereas the closed canal in Acontias (Acontidae) evolved independently. However, Sphenomorphidae (Asymblepharus and Scincella) + Eugongylidae (Ablepharus) retain a large anterior opening of the Meckelian canal, whereas only a small opening characterizes the basal node of Egerniidae and Mabuyidae, except for H. vittatus and H. septemtaeniatus. The closure of the Meckelian canal in these two taxa is less well developed in comparison with other mabuyid skinks. Thus, a heterochronic pedomorphic process might have played a role in the evolution of these skinks. The Meckelian canal condition supports the monophyly of Heremites.

pre‐quaternary fossil record
meckelian canal
skink


3D morphometric analysis of fossil canid skulls contradicts the suggested domestication of dogs during the late Paleolithic

Abstract: Whether dogs were domesticated during the Pleistocene, when humans were hunter-gatherers, or during the Neolithic, when humans began to form permanent settlements and engage in agriculture, remains controversial. Recently discovered Paleolithic fossil skulls, Goyet dated 31,680 +/− 250 YBP and Eliseevichi MAE 447/5298 dated 13,905 +/− 55 YBP, were previously identified as dogs. However, new genetic studies contradict the identification of these specimens as dogs, questioning the validity of traditional measurements used to morphologically identify canid fossil skulls. We employ 3D geometric morphometric analyses to compare the cranial morphology of Goyet and Eliseevichi MAE to that of ancient and modern dogs and wolves. We demonstrate that these Paleolithic canids are definitively wolves and not dogs. Compared to mesaticephalic (wolf-like breeds) dog skulls, Goyet and Eliseevichi MAE, do not have cranial flexion and the dorsal surface of their muzzles has no concavity near the orbits. Morphologically, these early fossil canids resemble wolves, and thus no longer support the establishment of dog domestication in the Paleolithic.


Deciphering the complete mitochondrial genome and phylogeny of the extinct cave bear in the Paleolithic painted cave of Chauvet

Abstract: Retrieving a large amount of genetic information from extinct species was demonstrated feasible, but complete mitochondrial genome sequences have only been deciphered for the moa, a bird that became extinct a few hundred years ago, and for Pleistocene species, such as the woolly mammoth and the mastodon, both of which could be studied from animals embedded in permafrost. To enlarge the diversity of mitochondrial genomes available for Pleistocene species, we turned to the cave bear (Ursus spelaeus), whose only remains consist of skeletal elements. We collected bone samples from the Paleolithic painted cave of Chauvet-Pont d'Arc (France), which displays the earliest known human drawings, and contains thousands of bear remains. We selected a cave bear sternebra, radiocarbon dated to 32,000 years before present, from which we generated overlapping DNA fragments assembling into a 16,810-base pair mitochondrial genome. Together with the first mitochondrial genome for the brown bear western lineage, this study provides a statistically secured molecular phylogeny assessing the cave bear as a sister taxon to the brown bear and polar bear clade, with a divergence inferred to 1.6 million years ago. With the first mitochondrial genome for a Pleistocene carnivore to be delivered, our study establishes the Chauvet-Pont d'Arc Cave as a new reservoir for Paleogenetic studies. These molecular data enable establishing the chronology of bear speciation, and provide a helpful resource to rescue for genetic analysis archeological samples initially diagnosed as devoid of amplifiable DNA.

mitochondrial genome
phylogeny
cave bear


The first Triassic ‘Protodonatan’ (Zygophlebiidae) from China: stratigraphical implications

Abstract: Abstract The clade Triadophlebioptera within the Odonatoptera greatly diversified and became widely distributed worldwide during the Triassic. Although abundant insect fossils have been reported from the Triassic of China, no Triassic dragonflies have been recorded. In this paper, Zygophlebia tongchuanensis sp. nov., the first species of Zygophlebiidae discovered outside the Madygen Formation of Kyrgyzstan, is described from the Middle–Upper Triassic Tongchuan Formation of Shaanxi Province, northwestern China. The discovery extends the distribution of the family Zygophlebiidae in Asia, indicating a high diversity of Triadophlebioptera during Middle–Late Triassic times. Combined with the palaeontological and geochronological evidence, the age of the Tongchuan Formation is considered to be Anisian – Early Carnian, and the insect-bearing layers are considered to be Ladinian.

triassic
zygophlebiidae
china
shaanxi province