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There is a strong relationship between metazoan body size and extinction risk. However, the size selectivity and underlying mechanisms in foraminifera, a common marine protozoa, remain controversial. Here, we found that foraminifera exhibit size-dependent extinction selectivity, favoring larger groups (>7.4 log10 cubic micrometer) over smaller ones. Foraminifera showed significant size selectivity in the Guadalupian-Lopingian, Permian-Triassic, and Cretaceous-Paleogene extinctions where the proportion of large genera exceeded 50%. Conversely, in extinctions where the proportion of large genera was

Fossils of large animals have long influenced social practices and ideologies in human societies, including the fantastic myths of giants, heroes, and gods in ancient Greece. It has been estimated that purposeful fossil collecting in Greece began in the Late Bronze Age. However, previous archaeological finds of fossils from mainland Greece were not well documented in secure contexts that dated this far back in time. Herein, we present a newly recognized fossilized astragalus bone recently found in the legacy collections of the archaeological site of Mycenae. It was originally recovered by excavations in the 1970s and recently reanalyzed at the Mycenae Museum. Our analysis explored the available evidence of the find location, the state of fossil preservation, and the species represented. The results suggest that a fossilized rhinoceros (Stephanorhinus) astragalus was collected in the past, possibly from afar. Evidence indicates it was brought to Mycenae, where it was deposited near an interesting array of artifacts in a basement storage area of the Southwest Quarter, sometime in the thirteenth century BCE. This find represents the earliest secure evidence of large animal fossil use by people in mainland Greece, dating to the Late Bronze Age.

The jaguar (Panthera onca) is the largest living cat species native to the Americas and one of few large American carnivorans to have survived into the Holocene. However, the extent to which jaguar diversity declined during the end-Pleistocene extinction event remains unclear. For example, Pleistocene jaguar fossils from North America are notably larger than the average extant jaguar, leading to hypotheses that jaguars from this continent represent a now-extinct subspecies (Panthera onca augusta) or species (Panthera augusta). Here, we used a hybridization capture approach to recover an ancient mitochondrial genome from a large, late Pleistocene jaguar from Kingston Saltpeter Cave, Georgia, United States, which we sequenced to 26-fold coverage. We then estimated the evolutionary relationship between the ancient jaguar mitogenome and those from other extinct and living large felids, including multiple jaguars sampled across the species' current range. The ancient mitogenome falls within the diversity of living jaguars. All sampled jaguar mitogenomes share a common mitochondrial ancestor ~400 thousand years ago, indicating that the lineage represented by the ancient specimen dispersed into North America from the south at least once during the late Pleistocene. While genomic data from additional and older specimens will continue to improve understanding of Pleistocene jaguar diversity in the Americas, our results suggest that this specimen falls within the variation of extant jaguars despite the relatively larger size and geographic location and does not represent a distinct taxon.

The Santa Barbara Basin is an extraordinary archive of environmental and ecological change, where varved sediments preserve microfossils that provide an annual to decadal record of the dynamics of surrounding ecosystems. Of the microfossils preserved in these sediments, benthic foraminifera are the most abundant seafloor-dwelling organisms. While they have been extensively utilized for geochemical and paleoceanographic work, studies of their morphology are lacking. Here we use a high-throughput imaging method (AutoMorph) designed to extract 2D data from photographic images of fossils to produce a large image and 2D shape dataset of recent benthic foraminifera from two core records sampled from the center of the Santa Barbara Basin that span an ~800-year-long interval during the Common Era (1249-2008 CE). Information on more than 36,000 objects is included, of which more than 22,000 are complete or partially-damaged benthic foraminifera. The dataset also includes other biogenic microfossils including ostracods, pteropods, diatoms, radiolarians, fish teeth, and shark dermal denticles. We describe our sample preparation, imaging, and identification techniques, and outline potential data uses.

Historical and ethnographic sources depict use of portable braced shaft weapons, or pikes, in megafauna hunting and defense during Late Holocene millennia in North and South America, Africa, Eurasia and Southeast Asia. Given the predominance of megafauna in Late Pleistocene North America during the centuries when Clovis points appeared and spread across much of the continent (13,050-12,650 cal BP), braced weapons may have been used in hunting of megaherbivores and defense against megacarnivores. Drawing from historical examples of pike use against lions, jaguars, boars, grizzlies, carabao and warhorses we consider the possibility of a fluted lithic pike. Associated osseous rods have been problematic as Clovis foreshafts due to the bevel angle and the apparent weakness of the splint haft when great strength is needed for deep penetration in megafauna hunting. However our review of Late Holocene pike use in megafauna encounters indicates the sharp tip becomes less important after hide or armor has been pierced because compression is sustained. Thus, foreshaft collapse after hide entry may not limit but rather increase the efficacy of the braced weapon. We conduct preliminary static experiments to model a fluted pike that adjusts during compression such that haft collapse and point detachment (when point jams on impact with bone) preserve the fluted biface, beveled rod and wooden mainshaft tip. In addition to Clovis point attributes and association with osseous rods, potential archaeological correlates of Clovis pike use include the high frequency of Clovis point isolates and concentrations of complete points with unbutchered mammoth remains at sites such as Naco in Arizona.

The phenomenon of lithic miniaturization during the Late Pleistocene at times coincided with increased artifact standardization and cutting edge efficiency-likely reflecting the use of small, sharp artifacts as interchangeable inserts for composite cutting tools and hunting weapons. During Marine Isotope Stage 2, Upper Paleolithic toolmakers in northern East Asia specifically used pressure techniques to make small, highly standardized lithic artifacts called microblades. However, little is currently known about how microblades affected the cutting edge efficiency of the toolkits they were a part of. We applied three methods of analyzing cutting edge efficiency to two Upper Paleolithic assemblages recently excavated from Tolbor-17, Mongolia, that document the periods before and after the introduction of microblade technology to the Tolbor Valley. A model incorporating allometric relationships between blank cutting edge length and mass suggests no difference in efficiency between the two periods, while two more conventional approaches both indicate a significant increase. The potential for improved cutting edge efficiency is only observed when the microblade sample is artificially inflated via simulation. Our results highlight challenges related to detecting and interpreting archaeological differences in cutting edge efficiency at the assemblage level.

Ontocetus is one of the most notable extinct odobenines owing to its global distribution in the Northern Hemisphere. Originating in the Late Miocene of the western North Pacific, this lineage quickly spread to the Atlantic Ocean during the Pliocene, with notable occurrences in England, Belgium, The Netherlands, Morocco and the eastern seaboard of the United States. Reassessment of a pair of mandibles from the Lower Pleistocene of Norwich (United Kingdom) and a mandible from the Upper Pliocene of Antwerp (Belgium) that were referred to as Ontocetus emmonsi reveals existences of features of both Ontocetus and Odobenus. The presence of four post-canine teeth, a lower canine larger than the cheek-teeth and a lower incisor confirms the assignment to Ontocetus; simultaneously, characteristics such as a fused and short mandibular symphysis, a well-curved mandibular arch and thin septa between teeth align with traits usually found in Odobenus. Based on a combination of these characters, we describe Ontocetus posti, sp. nov. Its mandibular anatomy suggests, a better adaptation to suction-feeding than what was previously described in the genus suggesting that Ontocetus posti sp. nov. likely occupied a similar ecological niche to the extant walrus Odobenus rosmarus. Originating from the North Pacific Ocean, Ontocetus most likely dispersed via the Central American Seaway. Although initially discovered in the Lower Pliocene deposits of the western North Atlantic, Ontocetus also left its imprint in the North Sea basin and Moroccan Plio-Pleistocene deposits. The closure of the Isthmus of Panama during the Mio-Pliocene boundary significantly impacted the contemporary climate, inducing global cooling. This event constrained Ontocetus posti in the North Sea basin leaving the taxon unable to endure the abrupt climate changes of the Early Pleistocene, ultimately going extinct before the arrival of the extant counterpart, Odobenus rosmarus.

Placerias hesternus, a Late Triassic dicynodont, is one of the last megafaunal synapsids of the Mesozoic. The species has a tusk-like projection on its maxillary bone, known as the caniniform process. This process has been hypothesized to be sexually dimorphic since the 1950s, however this claim has not been thoroughly investigated quantitatively. Here, we examined maxillae, premaxillae, quadrates, and fibulae from a single population from the Placerias Quarry in the Blue Mesa Member of the Chinle Formation, near St. Johns, Arizona, USA to determine if the caniniform process is dimorphic. We made a total of 25 measurements from the four bones and used a maximum likelihood framework to compare the fit of unimodal versus bimodal distributions for each set of measurements. Our results from complete maxillae reveal that the caniniform process has two distinct morphs, with a shorter and longer form. This interpretation is substantiated both by strong statistical support for bimodal distribution of caniniform lengths, and by clustering analysis that clearly distinguishes two morphs for the maxillae. Clustering analysis also shows support for potential dimorphism in the shape of the quadrate. However, no measurements from elements other than the maxilla have a strong likelihood of bimodal distribution. These results support the long-standing hypothesis that the caniniform in Placerias was dimorphic. Alternative explanations to sexual dimorphism that could account for the dimorphism among these fossils include the presence of juveniles in the sample or time-averaged sampling of a chronospecies, but both have been previously rejected for the Placerias Quarry population. The lack of strong dimorphism in non-maxilla elements and increased variation in caniniform length of the large-caniniform morph suggest that the caniniform is a secondary sexual trait, possibly used in intraspecific competition.

Extremes in organismal size have broad interest in ecology and evolution because organismal size dictates many traits of an organisms biology. There is particular fascination with identifying upper size extremes in the largest vertebrates, given the challenges and difficulties of measuring extant and extinct candidates for the largest animal of all time, such as whales, terrestrial non-avian dinosaurs, and extinct marine reptiles. The discovery of Perucetus colossus, a giant basilosaurid whale from the Eocene of Peru, challenged many assumptions about organismal extremes based on reconstructions of its body weight that exceeded reported values for blue whales (Balaenoptera musculus). Here we present an examination of a series of factors and methodological approaches to assess reconstructing body weight in Perucetus, including: data sources from large extant cetaceans; fitting published body mass estimates to body outlines; testing the assumption of isometry between skeletal and body masses, even with extrapolation; examining the role of pachyostosis in body mass reconstructions; addressing method-dependent error rates; and comparing Perucetus with known physiological and ecological limits for living whales, and Eocene oceanic productivity. We conclude that Perucetus did not exceed the body mass of todays blue whales. Depending on assumptions and methods, we estimate that Perucetus weighed 60-70 tons assuming a length 17 m. We calculated larger estimates potentially as much as 98-114 tons at 20 m in length, which is far less than the direct records of blue whale weights, or the 270 ton estimates that we calculated for body weights of the largest blue whales measured by length.

The diversity of vertebrate skeletons is often attributed to adaptations to distinct ecological factors such as diet, locomotion, and sensory environment. Although the adaptive evolution of skull, appendicular skeleton, and vertebral column is well studied in vertebrates, comprehensive investigations of all skeletal components simultaneously are rarely performed. Consequently, we know little of how modes of evolution differ among skeletal components. Here, we tested if ecological and phylogenetic effects led to distinct modes of evolution among the cranial, appendicular and vertebral regions in extant carnivoran skeletons. Using multivariate evolutionary models, we found mosaic evolution in which only the mandible, hindlimb and posterior (i.e. last thoracic and lumbar) vertebrae showed evidence of adaptation towards ecological regimes whereas the remaining skeletal components reflect clade-specific evolutionary shifts. We hypothesize that the decoupled evolution of individual skeletal components may have led to the origination of distinct adaptive zones and morphologies among extant carnivoran families that reflect phylogenetic hierarchies. Overall, our work highlights the importance of examining multiple skeletal components simultaneously in ecomorphological analyses. Ongoing work integrating the fossil and palaeoenvironmental record will further clarify deep-time drivers that govern the carnivoran diversity we see today and reveal the complexity of evolutionary processes in multicomponent systems.

The invasion of terrestrial ecosystems by tetrapods (c. 375 million years [Ma]) represents one of the major evolutionary transitions in the history of life on Earth. The success of tetrapods on land is linked to evolutionary novelties. Among these, the evolution of a tympanic ear contributed to mitigating the problem of an impedance mismatch between the air and the fluid embedding sound-detecting hair cells in the inner ear. 1,2,3 Pioneering studies advocated that similarities in the tympanic ear of tetrapods could only result from a single origin of this structure in the group, 4,5 an idea later challenged by paleontological and developmental data. 4,6,7,8 Current evidence suggests that this sensory structure evolved independently in amphibians, mammals, and reptiles, 1,6 but it remains uncertain how many times tympanic hearing originated in crown reptiles. 9,10 We combine developmental information with paleontological data to evaluate the evolution of the tympanic ear in reptiles from two complementary perspectives. Phylogenetically informed ancestral reconstruction analyses of a taxonomically broad sample of early reptiles point to the presence of a tympanic membrane as the ancestral condition of the crown group. Consistently, comparative analyses using embryos of lizards and crocodylians reveal similarities, including the formation of the tympanic membrane within the second pharyngeal arch, which has been previously reported for birds. Therefore, both our developmental and paleontological data suggest a single origin for the tympanic middle ear in the group, challenging the current paradigm of multiple acquisitions of tympanic hearing in living reptiles. [Display omitted] • Fossils reveal that the presence of tympanic membrane is ancestral to crown reptiles • The eardrum of lizards and crocodylians develops within the second pharyngeal arch • Fossils and embryos suggest a single origin of the tympanic ear in crown reptiles The tympanic ear is a key trait related to the evolutionary success of tetrapods on land, as it enhances the hearing capabilities of animals in this environment. Bronzati et al. use data from embryonic development and from the fossil record and provide evidence for a single origin of tympanic hearing in the group of living reptiles. [ABSTRACT FROM AUTHOR]

ABSTRACT This article provides a detailed taxonomic study of mammalian fossil fauna from five localities situated within the Middle Siwalik subgroup including the Nagri and Dhok Pathan formations in Punjab, Pakistan. Twenty‐three euungulate specimens comprised of isolated teeth, and maxillary and mandibular fragments, are described. This collection includes the bovid, Elachistoceras; a very rare faunal element in the Siwaliks of Pakistan, as well as Elachistoceras khauristanensis, Pachyportax latidens, Giraffa punjabiensis, Bramatherium grande, Merycopotamus dissimilis, Dorcatherium minus, Dorcatherium majus, Hippopotamodon sivalense, Sivalhippus theobaldi, Sivalhippus nagriensis and Brachypotherium perimense These fossil remains add important new insights into the taxonomy and diversity of Late Miocene mammal faunas of the Middle Siwaliks. The data is important for understanding the biogeographical and palaeoenvironmental history of the region. The characteristics of the fossils described in this study further support the currently hypothesised presence of a massive open land environment with variable wet and dry seasons alike to that of the current climate in Eurasia and Africa. The variable habitat niches of these co‐existing fauna also give further support to the supposition that there was a much more mixed array of palaeoenvironments ranging from a prevalence of woodland to expansive savannah territory during the deposition of Nagri and Dhok Pathan formations. [ABSTRACT FROM AUTHOR]

The genus Ilex (holly) in the monotypic family Aquifoliaceae contains more than 600 species distributed worldwide. Pollen fossils and macrofossils of fruits of Ilex are known from the late Cretaceous (90 Ma) and verified leaves from the upper Miocene (10 Ma), but until now only a few more or less incomplete flower fossils have been suggested as referable to this genus. This paper reviews the fossil flowers earlier attributed to Ilex and presents a complete and indisputable staminate Ilex flower from Baltic amber (34–38 Ma) examined in detail with synchrotron X-ray tomography. This finding may challenge the hypothesis of late Neogene dispersal of the genus from a center of origin in subtropical East Asia. [ABSTRACT FROM AUTHOR]

The fossil record of the U.S. Pacific Northwest preserves many Middle Miocene floras with potential for revealing long-term climate-vegetation dynamics during the Miocene Climatic Optimum. However, the possibility of strong, eccentricity-paced climate oscillations and concurrent, intense volcanism may obscure the signature of prevailing, long-term Miocene climate change. To test the hypothesis that volcanic disturbance drove Middle Miocene vegetation dynamics, high-resolution, stratigraphic pollen records and other paleobotanical data from nine localities of the Sucker Creek Formation were combined with sedimentological and geochemical evidence of disturbance within an updated chronostratigraphic framework based on new U-Pb zircon ages from tuffs. The new ages establish a refined, minimum temporal extent of the Sucker Creek Formation, ~15.8 to ~14.8 Ma, and greatly revise the local and regional chronostratigraphic correlations of its dispersed outcrop belt. Our paleoecological analysis at one ~15.52 Ma locality reveals two abrupt shifts in pollen spectra coinciding with the deposition of thick ash-flow tuffs, wherein vegetation dominated by Cupressaceae/Taxaceae, probably representing a Glyptostrobus oregonensis swamp, and upland conifers was supplanted by early-successional forests with abundant Alnus and Betula. Another ephemeral shift from Cupressaceae/Taxaceae swamp taxa in favor of upland conifers Pinus and Tsuga correlates with a shift from low-Ti shale to high-Ti claystone, suggesting a link between altered surface hydrology and vegetation. In total, three rapid vegetation shifts coincide with ash-flow tuffs and are attributed to volcanic disturbance. Longer-term variability between localities, spanning ~1 Myr of the Miocene Climatic Optimum, is chiefly attributed to eccentricity-paced climate change. Overall, Succor Creek plant associations changed frequently over ≤105 years timespans, reminiscent of Quaternary vegetation records. Succor Creek stratigraphic palynology suggests that numerous and extensive collection of stratigraphically controlled samples is necessary to understand broader vegetation trends through time. [ABSTRACT FROM AUTHOR]

Osteoderms, bone plates in the skin, are widely but discontinuously distributed across the phylogeny of tetrapods. This and their pronounced morphological disparity has inspired many hypotheses on possible osteoderm functions. Most of these have not been systematically studied or summarised based on the published disparate literature. We provide here a comprehensive overview of the current state of knowledge in this field with a focus on extant non‐avian reptiles. We also discuss functions in other extant osteoderm‐bearing taxa and those inferred from the fossil record. The hypotheses are categorised into protection, lifestyle and locomotion, physiology, and visual functions. A comprehensive overview of future directions in this field is provided. With this review, we hope to encourage future research to investigate the functional aspect of osteoderms. This might inspire biomimetics and shed light on the role that osteoderm expression may have played in shaping present‐day biodiversity. [ABSTRACT FROM AUTHOR]

Although the split of coelacanths from other sarcopterygians is ancient, around 420 million years ago, the taxic diversity and the morphological disparity of the clade have remained relatively low, with a few exceptions. This supposedly slow evolutionary pace has earned the extant coelacanth Latimeria the nickname "living fossil". This status generated much interest in both extinct and extant coelacanths leading to the production of numerous anatomical studies. However, detailed descriptions of extinct taxa are made difficult due to the quality of the fossil material which generally prevents fine comparisons with the extant Latimeria. Here we describe a new genus and species of coelacanth, Graulia branchiodonta gen. et sp. nov. from the Middle Triassic of Eastern France, based on microtomographical imaging using synchrotron radiation. Through exquisite 3D preservation of the specimens, we reconstructed the skeletal anatomy of this new species at an unprecedented level of detail for an extinct coelacanth, and barely achieved for the extant Latimeria. In particular, we identified a well-developed trilobed ossified lung whose function is still uncertain. The skeletal anatomy of G. branchiodonta displays the general Bauplan of Mesozoic coelacanths and a phylogenetic analysis resolved it as a basal Mawsoniidae, shedding light on the early diversification of one of the two major lineages of Mesozoic coelacanths. However, despite its exquisite preservation, G. branchiodonta carries a weak phylogenetic signal, highlighting that the sudden radiation of coelacanths in the Early and Middle Triassic makes it currently difficult to detect synapomorphies and resolve phylogenetic interrelationships among coelacanths in the aftermath of the great Permo-Triassic biodiversity crisis. [ABSTRACT FROM AUTHOR]

The colonization of land by animals was a milestone in the history of life. Approximately 100 million years before full terrestrialization, early animals sporadically traversed emergent subaerial substrates, leaving behind trace fossils recording their activities. However, identifying temporarily emergent environments and determining the affinities, motility and subaerial endurance of the trace-makers, and the timing and magnitude of their impacts on marginal-marine environments, are challenging. Here, we used semi-resolved computational fluid dynamics–discrete element method coupling to simulate trace formation on non-cohesive sediments in submerged and emergent subaerial conditions. This revealed instability-induced morphological signatures that allow us to identify the earliest terrestrial trace fossils. Quantitative metrics enable us to infer that the putative earliest terrestrial trace-makers were molluscs, and dimensional analysis suggests that their subaerial excursions could last at least 15 min. These organisms navigated emergent environments from the early Cambrian (stage 2), tens of millions of years earlier than arthropods. This quantitative paradigm provides new insights into the palaeobiology of the earliest subaerial bulldozers and highlights that mollusc-like animals were among the first ecosystem engineers to enter marginal-marine settings. They may thus have contributed to the establishment of marginal-marine biogeochemical cycles, laying the groundwork for subsequent terrestrialization by other animals. [ABSTRACT FROM AUTHOR]

ABSTRACT Mollusca, the second‐most diverse animal phylum, is estimated to have over 100,000 living species with great genetic and phenotypic diversity, a rich fossil record, and a considerable evolutionary significance. Early work on molluscan systematics was grounded in morphological and anatomical studies. With the transition from oligo gene Sanger sequencing to cutting‐edge genomic sequencing technologies, molecular data has been increasingly utilised, providing abundant information for reconstructing the molluscan phylogenetic tree. However, relationships among and within most major lineages of Mollusca have long been contentious, often due to limited genetic markers, insufficient taxon sampling and phylogenetic conflict. Fortunately, remarkable progress in molluscan systematics has been made in recent years, which has shed light on how major molluscan groups have evolved. In this review of molluscan systematics, we first synthesise the current understanding of the molluscan Tree of Life at higher taxonomic levels. We then discuss how micromolluscs, which have adult individuals with a body size smaller than 5 mm, offer unique insights into Mollusca's vast diversity and deep phylogeny. Despite recent advancements, our knowledge of molluscan systematics and phylogeny still needs refinement. Further advancements in molluscan systematics will arise from integrating comprehensive data sets, including genome‐scale data, exceptional fossils, and digital morphological data (including internal structures). Enhanced access to these data sets, combined with increased collaboration among morphologists, palaeontologists, evolutionary developmental biologists, and molecular phylogeneticists, will significantly advance this field. [ABSTRACT FROM AUTHOR]

Quantifying fair national shares of the remaining global carbon budget has proven challenging. Here, we propose an indicator—additional carbon accountability—that quantifies countries' responsibility for mitigation and CO2 removal in addition to achieving their own targets. Considering carbon debts since 1990 and future claims based on countries' emission pathways, the indicator uses an equal cumulative per capita emissions approach to allocate accountability for closing the mitigation gap among countries with a positive total excessive carbon claim. The carbon budget is exceeded by 576 Gigatonnes of fossil CO2 when limiting warming below 1.5 °C (50% probability). Additional carbon accountability is highest for the United States and China, and highest per capita for the United Arab Emirates and Russia. Assumptions on carbon debts strongly impact the results for most countries. The ability to pay for this accountability is challenging for Iran, Kazakhstan and several BRICS+ members, in contrast to the G7 members. In addition to national climate targets, the authors estimate countries' additional accountability to stay within the 1.5-degree carbon budget. They account for G7 countries having the highest carbon debts while several BRICS+ countries have high future claims. [ABSTRACT FROM AUTHOR]

Ankylosaurs were a group of heavily armored non‐avian dinosaurs (Dinosauria, Ankylosauria), represented by a relatively abundant fossil record from the Cretaceous of North and South America. Their dermal skeleton was characterized by large osteoderms whose development and functional role have been largely investigated. However, interstitial small ossicles, forming between these osteoderms, have been far more overlooked and it remains unknown whether they were formed through the ossification of a preexisting fibrous matrix of connective tissue (i.e., metaplasia) or by a cell‐induced differentiation of new fiber bundles followed by mineralization (i.e., neoplasia sensu (Zeitschrift für Wissenschaftliche Zoologie, 1858, 9, 147)). Here, we propose a hypothesis on the developmental origin of these small ossicles in the ankylosaurian Antarctopelta oliveroi using light microcopy, scanning electron microscopy and three‐dimensional virtual histology through propagation phase‐contrast synchrotron radiation micro‐computed tomography (PPC‐SRμCT). Ossicles are located in the dermis. They are composed of two layers: (1) a thin external layer, and (2) a thick basal plate, composed of collagen fiber bundles, which forms the main part of the ossicle. The external layer is made of a smooth, vitreous mineralized tissue that does not look like bone. The basal plate, however, is of osseous origin. In this basal plate, the collagen fiber bundles are organized in two orthogonal systems: one horizontal—observable in cross‐sections—and one vertical—observable in the primary plane of sections sensu (Journal of Vertebrate Paleontology, 2004, 24, 874). The horizontal system is itself composed of successive layers of collagen fiber bundles arranged into an orthogonal plywood‐like structure. The bundles of the vertical system radiate from the center of the ossicle at the level of the transition between the external layer and the basal plate and run towards the periphery of the basal plate. Their thickness increases from the center of the ossicle towards its periphery. Numerous bundles of the vertical system form thin threads that interweave and penetrate within the thick bundles of the horizontal system. Our new data suggest that the ossicles were at least partially formed by metaplasia, that is, through the ossification of a preexisting fibrous matrix of connective tissue. This process was probably supplemented by a cell‐induced differentiation of new fiber bundles laid down prior to their incorporation into the fibrous system and its mineralization. This process looks more akin to neoplasia sensu (Zeitschrift für Wissenschaftliche Zoologie, 1858, 9, 147) than to metaplasia. Consequently, metaplastic and neoplastic processes may coexist in these ossicles with a possible differential expression during ontogeny. [ABSTRACT FROM AUTHOR]

The Yanliao Biota from northern China is one of the most famous Mesozoic terrestrial lagerstätten in the world, with well-preserved fossil records in the Jurassic volcanic-sedimentary Ningcheng and Jianchang basins. However, the temporal evolution of the Yanliao Biota remains controversial, mainly due to the confusing stratigraphic framework and the unclear age of fossiliferous deposits in the Ningcheng basin. To address this issue, we carried out detailed field investigations and secondary ion mass spectrometry (SIMS) U-Pb age dating of zircons on fossiliferous and related strata in the southern part of the Ningcheng basin. The Jurassic infill of this area is composed of, in ascending order, fossil-bearing tuffaceous clastic rocks (unit 1), andesite and pyroclastic rocks (unit 2), fossil-bearing clastic rocks interlayered with minor volcanic rocks (unit 3), and andesite and pyroclastic rocks (unit 4). Integration of stratigraphic and geochronological data indicates that the Yanliao Biota in the Ningcheng basin appeared no later than ca. 163 Ma and lasted until ca. 156 Ma. A comparison with other analogous basins in northern China (e.g., the Luanping, Jianchang, and Beipiao basins) leads to the conclusion that the Yanliao Biota evolved in two phases and lasted for more than 11 m.y.: the first phase from ca. 167 Ma to ca. 163 Ma in the middle Bathonian to middle Callovian, followed by the second phase between ca. 161 Ma and ca. 156 Ma in the lower and middle Oxfordian. [ABSTRACT FROM AUTHOR]

A new species of Ovulidae J. Fleming, 1822 from the Nyalindung Formation, late Middle Miocene of West Java, Indonesia, is reported. The species is provisionally placed in the genus Dissona Cate, 1973, which, if confirmed, will be the first occurrence of this genus in the fossil record. [ABSTRACT FROM AUTHOR]

A new species of Ovulidae J. Fleming, 1822 from the Middle Miocene of Victoria, Australia, is reported. The species is provisionally placed in the genus Cuspivolva Cate, 1973, which, if confirmed, will be the first record of this genus in the fossil record of this part of the world. [ABSTRACT FROM AUTHOR]

Polymictic gravels exploited in the vicinity of Rugvica, SE from Zagreb, comprise clasts of various lithology, colour, shape, and size. Pebbles are composed of sedimentary, volcanic and, sporadically, metamorphic rocks. During the field work we recognized fossils in the abundant carbonate pebbles. Most of the carbonate clasts are rounded, discoidal in shape, varying in colour from white to dark grey, almost black. Pebbles were measured by a calliper and petrographic thin sections were prepared from fossiliferous pebbles. Numerical analyses pointed to some minor differences in their shape and size, but micropaleontological analyses revealed clasts of Carboniferous, Permian, Triassic, Jurassic, Cretaceous, Paleogene and Neogene age. Most of the Mesozoic and Cenozoic clasts originate from the two local mountain areas (Medvednica Mt. and Samobor Hills), with part of the Jurassic-Cretaceous pebbles possibly derived from SW Slovenia. Irregularly shaped and sometimes poorly rounded clasts of the Paleogene/Neogene ages seem to be abruptly transported to short distances by torrents or streams. The most enigmatic were the clasts of Carboniferous-Permian age. The nearest Palaeozoic outcrops occur upstream in Central Slovenia, but some fossils point to the even longer transport route, from the Karavanks in the upper flow of the Sava River. Gravels are overlain by fine-grained lake sediments and peat coal. Peat comprises significant amount of pine pollen, pointing to the warming period within the Late Pleistocene, which was additionally confirmed by the radiocarbon dating. [ABSTRACT FROM AUTHOR]

Background and Aims Cycads are a key lineage to understand the early evolution of seed plants and their response to past environmental changes. However, tracing the evolutionary trajectory of cycad species is challenging when the robust relationships at inter- or infrageneric level are not well resolved. Methods Here, using 2901 single-copy nuclear genes, we explored the species relationships and gene flow within the second largest genus of cycads, i.e. Zamia , based on phylotranscriptomic analyses of 90 % extant Zamia species. Based on a well-resolved phylogenetic framework, we performed gene flow analyses, molecular dating and biogeographical reconstruction to examine the spatiotemporal evolution of Zamia. We also performed ancestral state reconstruction of a total of 62 traits of the genus to comprehensively investigate its morphological evolution. Key Results Zamia comprises seven major clades corresponding to seven distinct distribution areas in the Americas, with at least three reticulation nodes revealed in this genus. Extant lineages of Zamia initially diversified around 18.4–32.6 (29.14) million years ago in Mega-Mexico, and then expanded eastward into the Caribbean and southward into Central and South America. Ancestral state reconstruction revealed homoplasy in most of the morphological characters. Conclusions This study revealed congruent phylogenetic relationships from comparative methods/datasets, with some conflicts being the result of incomplete lineage sorting and ancient/recent hybridization events. The strong association between the clades and the biogeographic areas suggested that ancient dispersal events shaped the modern distribution pattern, and regional climatic factors may have resulted in the following in situ diversification. Climate cooling starting during the mid-Miocene is associated with the global expansion of Zamia to tropical South America that has dramatically driven lineage diversification in the New World flora, as well as the extinction of cycad species in the nowadays cooler regions of both hemispheres, as indicated by the fossil records. [ABSTRACT FROM AUTHOR]

Fossils of the Ediacara Biota preserve the oldest evidence for complex, macroscopic animals. Most are difficult to constrain phylogenetically, however, the presence of rare, derived groups suggests that many more fossils from this period represent extant groups than are currently appreciated. One approach to recognize such early animals is to instead focus on characteristics widespread in animals today, for example multicellularity, motility, and axial polarity. Here, we describe a new taxon, Quaestio simpsonorum gen. et sp. nov. from the Ediacaran of South Australia. Quaestio is reconstructed with a thin external membrane connecting more resilient tissues with anterior‐posterior polarity, left‐right asymmetry and tentative evidence for dorsoventral differentiation. Associated trace fossils indicate an epibenthic and motile lifestyle. Our results suggest that Quaestio was a motile eumetazoan with a body plan not previously recognized in the Ediacaran, including definitive evidence of chirality. This organization, combined with previous evidence for axial patterning in a variety of other Ediacara taxa, demonstrates that metazoan body plans were well established in the Precambrian. [ABSTRACT FROM AUTHOR]

Vertebrate remains are scarce in the Cretaceous of Iran, with only a few records of fishes and one genus of chelonioid turtle known from the Dariyan and Sarvak formations. Here, we describe for the first time the paleoichthyological fauna of the Kazhdumi Formation, based on disarticulated microremains that represent the first record of vertebrates in the unit, highlighting this novel Albian–Cenomanian fossil assemblage. The fauna is composed of lamniform (cf. Dallasiella sp., cf. Paranomotodon sp., Anacoracidae indet., cf. Haimirichia amonensis, cf. Scapanorhynchus, Lamniformes indet.) sharks and pycnodontiforms Osteichthyes. [ABSTRACT FROM AUTHOR]

Premise of research. Roses have been horticulturally important for centuries, but their biogeographic history has remained largely unresolved. Fossil occurrences indicate that the genus was present in North America by the late Eocene and in Europe and Asia by the Oligocene. Given the age and importance of this genus, it is desirable to update as new fossils are uncovered and technologies advance. Methodology. Specimens preserved in lacustrine shales were studied by reflected light microscopy and micro–computed tomography scanning. Pivotal results. The fossil record of roses is summarized based on stipulate compound leaves and fruiting remains from western North America. Diagnostic characters of foliage and fruiting receptacles confirm identifications of Rosa from late Eocene, Oligocene, and Miocene sites in western North America and distinguish them from European and Asian fossil species. Rose hip species were found to vary in body shape and length of the apical neck. The hips from Colorado and Montana lacked prickles, while those from Oregon bore small prickles on the pedicel. Conclusions. A single largely uniform foliage type, R. hilliae Lesquereux, is recognized in the late Eocene and early Oligocene of western North America, while fruiting remains allow discrimination of two species, R. ruskiniana Cockerell from the late Eocene and early Oligocene of Colorado and Montana and R. mariae sp. nov. from the early Oligocene of Oregon. Another new species, R. packardae sp. nov., is recognized based on hips from the middle Miocene of Oregon. Reproductive structures were distinguished on the basis of differences in calyx lobing, receptacle shape, and epidermal projections on the pedicel. Among extant Rosa species, hip shapes are most commonly globose or subglobose, whereas North American fossils mostly display elliptical or urceolate hips. Urceolate hips in extant species are found in the subgenus Rosa , sections Cinnamomeae or Canieae, indicating potential infrageneric affinities for these fossils. [ABSTRACT FROM AUTHOR]

Premise of research. Abundant fossil records of Altingiaceae have been discovered from all Northern Hemisphere continents and suggest its widespread occurrence during the Paleogene, shedding light on its evolutionary history. However, records of unlobed Altingiaceae leaf fossils are rare and discovered only in East Asia to date. Methodology. Plant fossils were collected from the lignite opencast mine Profen-Süd in central Germany from late Eocene sediments of an alluvial coastal plain. From a total of 140 compressed leaves, cuticles were obtained from 52 specimens for studying epidermal characters. Leaf architecture and cuticle micromorphology were described and compared with fossil and extant species sharing similar characteristics. Pivotal results. The new material belongs to a rare and incompletely known fossil species from the same region and age. For taxonomic reasons, a new fossil genus— Zlatkophyllum gen. nov.—associated with Altingiaceae is established. Zlatkophyllum fischkandelii sp. nov. et comb. nov. is redescribed and reconsidered on the basis of the simple dentate, almost circular leaves with semicraspedodromous secondary vein framework; Ω-shaped anticlinal walls of epidermal cells; and brachyparacytic stomata. Conclusions. The new fossil genus is the first representative of Altingiaceae from the European Cenozoic with exclusively unlobed leaves, thus providing important implications for the evolutionary history of the family. In the fossil assemblage, Z. fischkandelii co-occurs with abundant Steinhauera subglobosa infructescences from the same family, and thus the new fossil taxon is hypothetically the previously unknown foliage of the S. subglobosa –producing fossil plant. [ABSTRACT FROM AUTHOR]

Premise of research. To date, there is no fossil evidence of the malpighiaceous genus Dicella Griseb. Here, we describe a new fossil species attributed to the modern Dicella Griseb. from the latest Neogene sediments (Rajdanda Formation: Pliocene) of Jharkhand, eastern India. Methodology. The five-winged fruit fossil was revealed by careful removal of the overlying matrix and studied under light compound and inverted fluorescence microscopes. It is identified on the basis of its detailed morphology and through comparison with other modern angiosperm genera having five-winged fruits. Pivotal results. Dicella indica Hazra, Manchester and Khan sp. nov. is characterized by winged fruits with five unequal, narrowly elliptic or obovate enlarged persistent sepals arising hypogynously from a globular nut; the sepals are enlarged with slightly constricted bases and obtuse apexes with venation consisting of a strong midvein and pinnate brochidodromous secondary veins, mixed percurrent tertiary veins, and irregular reticulate quaternary veins. Following comparison with numerous extant genera of angiosperms with propeller-like winged fruits, we conclude that this set of characters is diagnostic for the extant genus Dicella. Conclusions. It is interesting to note that, at present, Dicella does not naturally occur in India and is currently restricted to South America. We hypothesize that its disappearance from the present-day vegetation of eastern India may be related to the gradual intensification of rainfall seasonality since the Pliocene. Our discovery provides valuable insights into the biogeographic history of this genus. [ABSTRACT FROM AUTHOR]

Fruits of the caryophyllalean family Montiaceae are recognized from the latest Cretaceous Deccan Intertrappean beds of central India. Although initially interpreted as the sporocarp of an aquatic fern, Kuprianovites Nambudiri & Thomas was subsequently demonstrated to belong to the group Centrospermeae. The name Kuprianovites deccanensis Nambudiri & Thomas takes priority over subsequent synonyms, Centrospermocarpon chitaleyae Sheikh & Kubalkar, Deccanocarpon arnoldii Paradkar, and Portulacaceocarpon bhuterensis Borkar, Nagrale, Meshram, Korpenwar, & DD Ramteke. We studied anatomically preserved specimens using successive acetate peels and micro–computed tomography scanning. The fruits are thin-walled trivalved globose capsules bearing 30 or more seeds in free-central placentation. The seeds are ellipsoidal and bear strongly curved embryos. Although formerly assigned to the Portulacaceae as that family was traditionally circumscribed, the fossil is excluded from the Portulaca clade (i.e., Portulaceaceae s.s.) and conforms instead to the Montiaceae by its valvate, rather than circumscissile, capsules and valves with undifferentiated cell layers. [ABSTRACT FROM AUTHOR]

To develop a phytolith (biogenic silica) reference and to understand the eco-climatic indicative values of some grass silica short cells (GSSCs) occurring in the bamboos (Bambusoideae grasses), one of the chief floral components of eastern and north-eastern parts of India, we studied 44 modern bambusoid grasses and 26 surface soils from different eco-climatic zones covering both the plains and mountainous regions. Of the diverse phytoliths retrieved from the bamboos, Saddle tall and Saddle collapsed were the most abundant types (except in Yushania maling) and these types were also common in surface soil phytolith assemblages of the eastern and north-eastern parts of India. To assess the environmental sensitivity of most consistent morphotypes, we categorized two commonly occurring GSSC morphotypes namely S addle tall into three groups based on their length and S addle collapsed into two groups based on their length to width ratio respectively. Pearson's correlation analysis, principal component analysis (PCA), and redundancy analysis (RDA) were used to understand if these morphotypes could distinguish different eco-climatic conditions. Variability of S addle tall and S addle collapsed types (both morphometric and abundance) in bamboos growing in these parts of India is a function of mean precipitation of the wettest quarter (MPWeQ) and mean temperature of the driest quarter (MTDQ). The present results served as a baseline for reevaluating the interpretations of a Late-Holocene fossil phytolith record from the eastern Himalaya further validating the potential of S addle tall and S addle collapsed types in reconstructing past climate variability in a wide geographical region. [ABSTRACT FROM AUTHOR]

A remarkable new genus and species of cyclostome bryozoans is described from the Sea of Okhotsk off the Kamchatka Peninsula, Russia. Kamchatkapora ozhgibesovigen. et sp. n. has large, multilayered colonies, each layer constructed of numerous subcolonies joined at their outer edges. This colony-form was previously unknown in extant cyclostomes, although common in the geological past, especially during the Cretaceous period. The term 'stratocormidial' is here introduced for such colonies, and their taxonomy and geological history are reviewed. Six fossil stratocormidial cyclostome genera (Blumenbachium, Cellulipora, Centronea, Multifascigera, Reptomulticava and Semimulticavea) are illustrated and briefly characterised. [ABSTRACT FROM AUTHOR]

The superfamily Stromboidea is a clade of morphologically distinctive gastropods which include the iconic Strombidae, or 'true conchs'. In this study, we present the most taxonomically extensive phylogeny of the superfamily to date, using fossil calibrations to produce a chronogram and extant geographical distributions to reconstruct ancestral ranges. From these results, we confirm the monophyly of all stromboidean families; however, six genera are not monophyletic using current generic assignments (Strombidae: Lentigo, Canarium, Dolomena, Doxander; Xenophoridae: Onustus, Xenophora). Within Strombidae, analyses resolve an Indo‐West Pacific (IWP) clade sister to an East Pacific/Atlantic clade, together sister to a second, larger IWP clade. Our results also indicate two pulses of strombid diversification within the Miocene, and a Tethyan/IWP origin for Strombidae—both supported by the fossil record. However, conflicts between divergence time estimates and the fossil record warrant further exploration. Species delimitation analyses using the COI barcoding gene support several taxonomic changes. We synonymise Euprotomus aurora with Euprotomus bulla, Strombus alatus with Strombus pugilis, Dolomena abbotti with Dolomena labiosa, and Dolomena operosa with Dolomena vittata. We identified cryptic species complexes within Terebellum terebellum, Lambis lambis, "Canarium" wilsonorum, Dolomena turturella and Maculastrombus mutabilis. We reinstate Rimellopsis laurenti as a species (previously synonymised with R. powisii) and recognise Harpago chiragra rugosus and Lambis truncata sowerbyi valid at the rank of species. Finally, we establish several new combinations to render Lentigo, Dolomena, and Canarium monophyletic: Lentigo thersites, Dolomena robusta, Dolomena epidromis, Dolomena turturella, Dolomena taeniata, Dolomena vanikorensis, D. vittata, "Canarium" wilsonorum, Hawaiistrombus scalariformis, Maculastrombus mutabilis, Maculastrombus microurceus. [ABSTRACT FROM AUTHOR]

Neogastropoda is a large order of predominantly marine gastropod molluscs, typically predatory or parasitic on other animals. It includes over 16,000 species representing a large post‐Cretaceous radiation, but the internal phylogenetic relationships of contained taxa are far from resolved, with inconsistent results from nuclear genes, mitogenomes, and morphology. One major issue in reconstructing the molecular phylogeny is the lack of high‐quality sequences for early‐diverging families and superfamilies such as Volutidae (Volutoidea). Here, we examine the superfamily‐level phylogenetic relationships in Neogastropoda, aided by newly sequenced draft genome and mitogenome of the volutid snail Fulgoraria chinoi from the deep sea off Japan. The genome of F. chinoi is relatively large at 1.54 Gb but exhibits low genome heterozygosity; over 54% of this genome constitutes of repeat contents, and we find evidence for active insertion of transposable elements, particularly LINEs and SINEs. A total of 50,792 protein‐coding genes (PCGs) were predicted from the nuclear genome, and a circular mitogenome was also assembled and annotated. Our phylogenetic analyses using mitogenomes recovered each neogastropod superfamily as monophyletic, though also revealed inconsistent phylogenetic signals within superfamilies. Phylogenetic reconstructions using the PCGs resulted in a robust tree from different models and data matrices, recovering Volutoidea as the earliest diverging superfamily (among those for which comparable data is available) within a monophyletic Neogastropoda. Dated phylogenetic analysis revealed an early Cretaceous radiation of Neogastropoda, congruent with the fossil record. Our study provides a robust internal evolutionary framework for the speciose but genomically undersampled Neogastropoda, and expands the available genomic resources for this order. Genomic data for key missing lineages such as Mitroidea, Olivoidea, and Cancellariidae are much sought in the future for a full understanding of Neogastropoda evolution. [ABSTRACT FROM AUTHOR]

Summary: Accurate divergence times are essential for interpreting and understanding the context in which lineages have evolved. Over the past several decades, debates have surrounded the discrepancies between the inferred molecular ages of crown angiosperms, often estimated from the Late Jurassic into the Permian, and the fossil record, placing angiosperms in the Early Cretaceous. That crown angiosperms could have emerged as early as the Permian or even the Triassic would have major implications for the paleoecological context of the origin of one of the most consequential clades in the tree of life. Here, we argue, and demonstrate through simulations, that the older ages inferred from molecular data and relaxed‐clock models are misled by lineage‐specific rate heterogeneity resulting from life history changes that occurred several times throughout the evolution of vascular plants. To overcome persistent discrepancies in age estimates, more biologically informed and realistic models should be developed, and our results should be considered in the context of their biological implications before we accept inferences that are a major departure from our strongest evidence. [ABSTRACT FROM AUTHOR]

We describe a small collection of Late Ordovician gastropods Holopea? sp. Hormotoma sp. Poleumita? sp. Gyronema rupestre; cephalopod Discoceras sp. unidentified Nautiloids, and rare Tentaculites sp. from the Takche Formation (Ordovician-Silurian) exposed in the Tidong Valley (Kinnaur) of the Tethyan Himalaya. This is the first report of mollusc fossils from the Ordovician-Silurian successions of the Tidong Valley, Kinnaur. The reported Late Ordovician gastropods are also known from Baltica, suggesting a probable oceanic link between these remote regions. Tentaculites from the Takche Formation does not resemble any Baltic or North American tentaculitoids and show greater resemblance to the tentaculitoids from the other Gondwanan regions. [ABSTRACT FROM AUTHOR]

Summary The primary vascular system of plants (the stele) has attracted interest from paleobotanists, developmental biologists, systematists, and physiologists for nearly two centuries. Ferns, with their diverse stelar morphology, deep evolutionary history, and prominent fossil record, have been a major focus in studies of the stele. To explain the diversity of stelar morphology, past adaptive hypotheses have invoked biomechanics, hydraulics, and drought tolerance as key selection pressures in the evolution of stelar complexity; but, these hypotheses often isolate the stele from a whole‐plant developmental context, ignoring potential covariation between vascular patterning and shoot morphology. Furthermore, incongruence between expected patterns and observed data challenge adaptive hypotheses, precluding a comprehensive explanation of stelar evolution. While ontogeny has been previously recognized as a factor in stelar diversification, it has not been fully integrated into a comprehensive framework. Here we synthesize 150‐years of research on stelar morphology, incorporating developmental, physiological, and phylogenetic data to present the ontogenetic hypothesis of stelar evolution. This hypothesis posits that stelar morphology is an integrated feature of whole‐plant ontogeny, not a trait shaped by direct selection for adaptive patterns. This shift in perspective provides an updated framework for understanding the determinants of stelar morphology and focusses future efforts to ask more incisive questions about the evolution and function of primary vascular architecture. [ABSTRACT FROM AUTHOR]

Premise Methods Results Conclusions The ecological conditions that constrain plants to an environmental niche are assumed to be constant through time. While the fossil record has been used previously to test for niche conservatism of woody flowering plants, additional studies are needed in other plant groups especially since they can provide insight with paleoclimatic reconstructions, high biodiversity in modern terrestrial ecosystems, and significant contributions to agriculture.We tested climatic niche conservatism across time by characterizing the climatic niches of living herbaceous ginger plants (Zingiberaceae) and woody dawn redwood (Metasequoia) against paleoniches reconstructed based on fossil distribution data and paleoclimatic models.Despite few fossil Zingiberaceae occurrences in the latitudinal tropics, unlike living Zingiberaceae, extinct Zingiberaceae likely experienced paratropical conditions in the higher latitudes, especially in the Cretaceous and Paleogene. The living and fossil distributions of Metasequoia largely remain in the upper latitudes of the northern hemisphere. The Zingiberaceae shifted from an initial subtropical climatic paleoniche in the Cretaceous, toward a temperate regime in the late Cenozoic; Metasequoia occupied a more consistent climatic niche over the same time intervals.Because of the inconsistent climatic niches of Zingiberaceae over geologic time, we are less confident of using them for taxonomic‐based paleoclimatic reconstruction methods like nearest living relative, which assume a consistent climatic niche between extant and extinct relatives; we argue that the consistent climatic niche of Metasequoia is more appropriate for these reconstructions. Niche conservatism cannot be assumed between extant and extinct plants and should be tested further in groups used for paleoclimatic reconstructions. [ABSTRACT FROM AUTHOR]

ABSTRACT Drilling predation on echinoids (sea urchins) has been known to occur in marine ecosystems since the Jurassic Period; however, it has rarely been studied in existing species. Tests of the irregular sea urchin Brissus unicolor (Leske, 1778), which frequently occurs in shallow substrates of the Canary Islands, mostly show very evident perforations through their skeletons. The aim of this study was to describe the characteristics of these perforations in order to determine their possible origins as well as document their size, site selectivity, and frequency of occurrence among different sample sites. Of the 104 tests of B. unicolor that were collected from 15 locations off the island of Tenerife (Canary Islands, Spain), 94% showed a least one perforation. These boreholes exhibit a circular morphology, penetrating the sea urchin tests perpendicularly and entirely. Notably, they display a unique acid signature, diverging from those documented in the fossil record and other relevant studies. Our analysis showed size and site selectivity by the predator as the perforations were mainly located on the oral side of the test. The perforations are attributed to drilling predation. The characteristics of these boreholes on B. unicolor match published records of predation marks suggesting that they are produced by the predatory gastropod family Cassidae, with Semicassis undulata (Gmelin, 1791) considered to be the most probable predator. [ABSTRACT FROM AUTHOR]

Deciduous dentition of extinct mammals has traditionally received little attention based on its poor representation in the fossil record. However, several aspects related to this tooth locus could have important evolutionary significance (time of replacement, retention throughout life, and morphology). In this work, we described a new specimen from late Oligocene levels of Cabeza Blanca (Chubut Province, Argentina). This fossil corresponds to a maxillary fragment with a deciduous premolar (DP4) assigned herein to Cephalomys arcidens based on morphological characteristics, size, and comparisons with other late Oligocene-Early Miocene caviomorphs. It can be identified as a DP4 due to its mesiodistally longer than wide diameter, shallow flexi, complex tooth morphology, and its position in the maxillary fragment. This is the first description of the DP4 of a Cephalomyidae and the last unknown dental locus of Cephalomys arcidens. Now, C. arcidens is one of the better-known late Oligocene caviomorphs since it is recognised through the complete dentition, crania, and mandibles. In addition, this new information would be used to evaluate the importance of deciduous dentition in resolving phylogenetic relationships in the enigmatic cephalomyids in particular and in Caviomorpha in general. [ABSTRACT FROM AUTHOR]

Many of the developmental innovations that underpin the diversity of plant form alive today, such as those facilitating apical growth, branching, leaves, roots, wood and seeds, all evolved over 360 million years ago. Fossils, as our only direct record of plant form in the past, are thus essential for interpreting the origin and evolution of these innovations. The focus of this Spotlight is to showcase the rich plant fossil record open for developmental interpretation and to cement the role that fossils play at a time when increases in genome sequencing and new model species make tackling major questions in the area of plant evolution and development tractable for the first time. [ABSTRACT FROM AUTHOR]

Higher alcohol synthesis through the Fischer–Tropsch (F–T) process was considered a promising route for the efficient utilization of fossil resources could be achieved. The CuCo catalysts were proven to be efficient candidates and attracted much interest. Great efforts have been made to investigate the active sites and mechanisms of CuCo catalysts. However, the industrialized application of CuCo catalysts in this process was still hindered. The poor stability of this catalyst was one of the main reasons. This short review summarized the recent development of active sites on the CuCo catalysts for higher alcohol synthesis, including CuCo alloy particles, CuCo core–shell particles, and unsaturated particles. The complex active sites and their continual changes during the reaction led to the poor stability of the catalysts. The effect of active sites on catalytic performance was discussed. Furthermore, the key factors in fabricating stable CuCo catalysts were proposed. Finally, reasonable proposals were proposed for designing efficient and stable CuCo catalysts in higher alcohol synthesis. [ABSTRACT FROM AUTHOR]

The production of materials based on fossil resources is yielding more sustainable and ecologically beneficial methods. Vegetable oils (VO) are one example of base materials whose derivatives rival the properties of their petro‐based counterparts. Gaps exist however and one way to fill them is by employing sol–gel processes to synthesize organic–inorganic hybrid materials, often derived from silane/siloxane compounds. Creating Si─O─Si inorganic networks in the organic VO matrix permits the attainment of necessary strength, among other property enhancements. Consequently, many efforts have been directed to optimally achieve organic–inorganic hybrid materials with VOs. However, compatibilization is challenging, and desirable conditions for matching the inorganic filler in the organic matrix remain a key stumbling block toward wider application. Therefore, this review aims to detail recent progress on these new hybrids, focusing on the main strategies to polymerize and functionalize the raw VO, followed by routes highlighting the addition of the inorganic fillers to obtain desirable composites. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous Ganzhou Basin of Jiangxi Province, South China is among one of the richest egg fossil sites in the world and yields abundant exquisite egg clutches and embryonic eggs, especially in oviraptorosaurs. Hadrosaurian, troodontid, and potential dromaeosaurid egg fossils were also reported, though they were rare. All these reported eggs vary in morphology but have relatively large sizes. Here, we report a partial egg clutch with six complete small eggs from the Upper Cretaceous Tangbian Formation of Ganzhou City, Southeast China. The microstructure of the eggshell indicates that it can be assigned to Ovaloolithidae. Hence, we established a new ootaxon, Minioolithus ganzhouensis oogen. et oosp. nov. based on a unique combination of characters, including a small egg size, irregular egg arrangement, worm-like and nodular ornamentation, and a gradual boundary between two structural layers. The egg morphology and eggshell microstructure support it to be the smallest known non-avian theropod egg up to date. This discovery increases the diversity of dinosaur eggs in the Late Cretaceous and is significant for our understanding of the evolution of theropods in the Late Cretaceous. [ABSTRACT FROM AUTHOR]

Three types of plant-insect interactions are identified on seeds from the lower Permian (Asselian) Shanxi and lower Shihhotse formations of the Taiyuan district, North China. This enhances the relatively meagre fossil record of seed predation in global late Paleozoic floras, adding the earliest record of granivory from Cathaysia. The dispersed seeds cannot be attributed with confidence to any particular plant group, but associated fossil leaves belong to a broad spectrum of plants, including Medullosales, Cycadales, Noeggerathiales, Gigantopteridales, Cordaitales, and Voltziales. Among 85 analysed seeds, six showed evidence of predation, referable to three damage types: DT074 and two new damage types that will be added to the forthcoming version of the fossil damage guide (DT274, DT430). These damage features indicate novel strategies of seed exploitation in the earliest Permian of China. The causal agents of the seed herbivory are difficult to resolve with certainty, but possible culprits include representatives of Palaeodictyopteroidea, although we cannot exclude other groups, such as Dictyoptera, Odonatoptera, Archaeorthoptera, Hemipteroidea or early holometabolan insects. The presence of damage features, together with a range of probable defensive structures (hairs, spines, apical horns, and thick integuments), suggests that an active arms race involving insects and plant reproductive structures was already well established by the early Permian. [ABSTRACT FROM AUTHOR]

Enantiornithines were the most diverse group of birds during the Cretaceous, comprising over half of all known species from this period. The fossil record and subsequently our knowledge of this clade is heavily skewed by the wealth of material from Lower Cretaceous deposits in China. In contrast, specimens from Upper Cretaceous deposits are rare and typically fragmentary, yet critical for understanding the extinction of this clade across the K-Pg boundary. The most complete North American Late Cretaceous enantiornithine is Mirarce eatoni, a member of the diverse clade Avisauridae. Except for Mirarce, avisaurids are known only from isolated hindlimb elements from North and South America. Here we describe three new enantiornithines from the Maastrichtian Hell Creek Formation, two of which represent new avisaurid taxa. These materials represent a substantial increase in the known diversity of Enantiornithes in the latest Cretaceous. Re-examination of material referred to Avisauridae through phylogenetic analysis provides strong support for a more exclusive Avisauridae consisting of six taxa. Exploration of the functional morphology of the avisaurid tarsometatarsus indicates potential strong constriction and raptorial attributes. The lower aspect ratio of the tarsometatarsus facilitates a more biomechanically efficient lever system which in extant birds of prey equates to lifting proportionally heavier prey items. In addition, the proportional size and distal position of the m. tibialis cranialis tubercle of the tarsometatarsus is similar to the morphology seen in extant birds of prey. Together with the deeply-grooved metatarsal trochlea facilitating robust and likely powerful pedal digits, morphologies of the hindlimb suggest avisaurids as Late Cretaceous birds of prey. [ABSTRACT FROM AUTHOR]

The history of Panthera throughout Asia is dependent on a very scant fossil record. Dominating Asia in the Holocene, Pleistocene Panthera fossils have often been attributed to Panthera tigris. However, newer finds suggest that there was more than just P. tigris in Pleistocene Asia. Rather, species previously thought to be only from western Eurasia have been uncovered in South and East Asia, including Panthera spelaea and Panthera gombaszogensis. Therefore, re-evaluation of the fossil Panthera from Pleistocene Sunda is indicated. A partial mandible from Kedung Brubus (MIS 20–15) shows characteristics distinct from both contemporary Pleistocene P. tigris and Holocene Sunda populations. Rather, this specimen shows strong affinities with the Eurasian P. gombaszogensis. The Kedung Brubus mandible therefore provides the first evidence for the presence of P. gombaszogensis in Middle Pleistocene Sunda, becoming extinct some time after the arrival of P. tigris. [ABSTRACT FROM AUTHOR]

New post-cranial remains from the early Late Miocene have been discovered in the lowermost part of the Irrawaddy Formation, Tebingan area, central Myanmar. Three genera and one indeterminate taxon were identified: Rhinoceros sp. Rhinoceros cf. R. sondaicus, Dicerorhinus sp., Brachypotherium perimense, and Rhinocerotidae indet. The evolutionary history of the Rhinocerotidae is still poorly known in Southeast Asia. Few Rhinoceros species, Rhinoceros sp. ‘B’. fatehjangense, and B. perimense, has already been identified in the Tebingan area by dental remains. The present discovery of the post-cranial remains of Rhinoceros cf. R. sondaicus and Dicerorhinus sp. that complements previous studies based on dental remains. The early Late Miocene Tebingan record is the oldest fossil record of Dicerorhinus in Southeast Asia, indicating a continental origin of the genus. Furthermore, the possible presence of R. sondaicus in the Tebingan area suggests that it may have appeared in Southeast Asia as early as the early Late Miocene. [ABSTRACT FROM AUTHOR]