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Sus arvernensis is a Pliocene species that occupies a key position in the evolution of suids (Suidae, Artiodactyla, Mammalia) in Eurasia, and besides, it is considered important for biochronological correlations and paleoecological inferences. However, our knowledge on S. arvernensis is largely based on fossil remains from southwestern Europe. Here, we present a revision of the Hungarian fossil record of S. arvernensis. Up to now, the species was known from only two localities of Hungary, Gödöllő (central Hungary) and Süttő (northwest Hungary), and the latter occurrence has even been questioned. After the comparison with other relevant samples of S. arvernensis, of the Early Pleistocene S. strozzii, and of the extant wild boar S. scrofa (motivated by previous attributions and the chronology of the localities), the presence of S. arvernensis from Gödöllő and Süttő is confirmed, and more material of the species is described from Beremend (southern Hungary) and Kisláng (western Hungary). Collectively, the results of the revision carried out herein reveal a relatively widespread distribution of S. arvernensis in Hungary, hence providing an important link from the eastern to western European fossil record of the species. The specimens from Gödöllő and Süttő are slightly larger than the other material of S. arvernensis from France and Italy included in the biometric comparison, although the paucity of the material precludes to evaluate whether these differences are significant and to relate them to a chronological and/or geographical context. The occurrence of S. arvernensis in the Hungarian localities considered in this work is a biochronological indication of an age older than at least 2.6 Ma, since the species is not recorded after the Pliocene–Pleistocene transition. This in agreement with the age estimates available so far for some of the localities or provides new insights. At Süttő, in particular, the identification of S. arvernensis reinforces the view that travertine deposition started already in the Pliocene. [ABSTRACT FROM AUTHOR]

Aim: Within the intensively‐studied, well‐documented latitudinal diversity gradient, the deep‐sea biodiversity of the present‐day Norwegian Sea stands out with its notably low diversity, constituting a steep latitudinal diversity gradient in the North Atlantic. The reason behind this has long been a topic of debate and speculation. Most prominently, it is explained by the deep‐sea glacial disturbance hypothesis, which states that harsh environmental glacial conditions negatively impacted Norwegian Sea diversities, which have not yet fully recovered. Our aim is to empirically test this hypothesis. Specific research questions are: (1) Has deep‐sea biodiversity been lower during glacials than during interglacials? (2) Was there any faunal shift at the Mid‐Brunhes Event (MBE) when the mode of glacial–interglacial climatic change was altered? Location: Norwegian Sea, deep sea (1819–2800 m), coring sites MD992277, PS1243, and M23352. Time period: 620.7–1.4 ka (Middle Pleistocene–Late Holocene). Taxa studied: Ostracoda (Crustacea). Methods: We empirically test the deep‐sea glacial disturbance hypothesis by investigating whether diversity in glacial periods is consistently lower than diversity in interglacial periods. Additionally, we apply comparative analyses to determine a potential faunal shift at the MBE, a Pleistocene event describing a fundamental shift in global climate. Results: The deep Norwegian Sea diversity was not lower during glacial periods compared to interglacial periods. Holocene diversity was exceedingly lower than that of the last glacial period. Faunal composition changed substantially between pre‐ and post‐MBE. Main conclusions: These results reject the glacial disturbance hypothesis, since the low glacial diversity is the important precondition here. The present‐day‐style deep Norwegian Sea ecosystem was established by the MBE, more specifically by MBE‐induced changes in global climate, which has led to more dynamic post‐MBE conditions. In a broader context, this implies that the MBE has played an important role in the establishment of the modern polar deep‐sea ecosystem and biodiversity in general. [ABSTRACT FROM AUTHOR]

Simple Summary: The Republic of India is a tropical megadiverse country, encompassing four global biodiversity hot-spots and harboring 1379 butterfly species within its borders. Despite a long history of documenting Indian biodiversity, there are extremely few quantitative studies that have analyzed species-richness patterns within the country. We capitalized on the division of the country into 36 federal states and territories, and compiled and revised per-states butterfly checklists. Then, we analyzed the species-richness patterns, as well as the richness of endemic species and the numbers of species belonging to main biogeographic elements with respect to geography, climate, land covers and socioeconomic conditions of the administrative units. Such common macroecological predictors as area, latitude and land covers diversity did not affect the species richness, whereas the topographic diversity and energy availability had major effects. This is due to the peculiar biogeography of India, i.e., the peninsula narrowing towards the Equator, being isolated from the northern mainland by high mountains, and connected to species-rich eastern regions by only a narrow conduit. In multiple regression models, geographic variables were the strongest predictors of species-richness patterns, followed by climate and land covers. Our approach can be used as an initial step toward understanding distribution patterns in those regions of the world, for which detailed distribution data are not yet available but checklists per administrative units exist. Butterflies are widely used to analyze biogeographical patterns, both at the global and regional scales. Thus far, most of the latter originated from well-surveyed northern regions, while the species-rich tropical areas lag due to a lack of appropriate data. We used checklists of 1379 butterfly species recorded in 36 federal states of the Republic of India (1) to explore the basic macroecological rules, and (2) to relate species richness and the distribution of endemics and geographic elements to geography, climate, land covers and socioeconomic conditions of the states. The area, land covers diversity and latitude did not affect species richness, whereas topographic diversity and the precipitation/temperature ratio (energy availability) were positive predictors. This is due the geographic and climatic idiosyncrasies of the Indian subcontinent, with its highest species richness in the small, densely forested mountainous northeast that receives summer monsoons. The peninsular effect that decreases the richness towards the tip of subcontinent is counterbalanced by the mountainous forested Western Ghats. Afrotropical elements are associated with savannahs, while Palearctic elements are associated with treeless habitats. The bulk of Indian butterfly richness, and the highest conservation priorities, overlap with global biodiversity hotspots, but the mountainous states of the Western Himalayas and the savannah states of peninsular India host distinctive faunas. [ABSTRACT FROM AUTHOR]

The Early Pleistocene site of Quibas, in Sierra de Quibas (Murcia, Spain) was discovered in 1994 and has since then provided abundant material of typical Epivillafranchian taxa. This biochron belongs to the Early-Middle Pleistocene transition (1.2 -- 0.78 Ma), characterised by a change in orbital cyclicity from a 41 kyr cycle to 100 kyr that intensified the climate and culminated in the most important faunal turnover of the Pleistocene regarding large mammals. The Group of Paleoanthropology of the National Museum of Natural Sciences (CSIC, Spain) and the Institut Català de Paleoecologia Humana i Evolució Social (IPHES-CERCA, Spain) carried out four field seasons from 2015 to 2018. Here we present the large herbivorous mammals recovered from the field, including the first citation of two taxa new to the locality: Stephanorhinus cf. etruscus and Bison cf. voigtstedtensis. We also provide the first description of previously mentioned taxa: Dama cf. vallonnetensis and Sus sp. Together with the remaining herbivores, the faunal community shows a strong European affinity with some regionalism. Compared with other Iberian localities, the site of Quibas stands out for the lack of hominin fossils or any evidence supporting their presence in the area, a peculiar scenario given that the Early-Middle Pleistocene transition broadly speaking sees the arrival of humans into Europe. [ABSTRACT FROM AUTHOR]

Several remains of fossil phocids (i.e., true seals) have been consistently reported from the Late Miocene and Pliocene strata from the southwestern coast of South America. These fossils, along with those from fossil otariids (fur seals and sea lions), indicate that a widespread turnover from a phocid-to an otariid-dominated fauna in the Southern Hemisphere transpired during the Late Pliocene or Early Pleistocene. The Neogene fossil record of phocids is primarily dominated by occurrences from southern Peru and northern Chile, with a few isolated findings from central Chile. Until now, no records of fossil seals have been documented from southern Chile, constraining our understanding of the latitudinal variability of the pinniped assemblages and the mechanisms by which their faunal turnover occurred. Here we report the fossil remains of a fossil seal (Monachinae indet.) from the Late Miocene-Pliocene sediments of Guafo Island in the south of Chile. These remains constitute the southernmost occurrence of a fossil seal from the South Pacific Ocean, expanding their geographic range in the southeastern coast of South America more than 1000 km. This finding reveals that phocids inhabited temperate and subantarctic regions in Chilean Patagonia during the late Neogene, suggesting a broader environmental tolerance than previously recognized. [ABSTRACT FROM AUTHOR]

The Suidae from the late Miocene of Alsótelekes (northeastern Hungary, Borsod-Abaúj-Zemplén county) are described and assigned to Propotamochoerus palaeochoerus (Suinae) and cf. Parachleuastochoerus (Tetraconodontinae). The co-occurrence of these two taxa agrees with a reference to the early Vallesian (MN 9), as previously indicated from biochronological correlation of the small mammal fauna, and suggests the presence of woodland environments, with abundance of below-ground resources and direct access to water. This fits well with the diverse wetlands and riparian forests that characterized Lake Pannon ∼10 Ma, as documented in the geographically close site of Rudabánya. The convoluted taxonomy of European Tetraconodontinae is discussed. [ABSTRACT FROM AUTHOR]

All ∼14,000 extant ant species descended from the same common ancestor, which lived ∼140–120 million years ago (Ma). 1,2 While modern ants began to diversify in the Cretaceous, recent fossil evidence has demonstrated that older lineages concomitantly occupied the same ancient ecosystems. 3 These early-diverging ant lineages, or stem ants, left no modern descendants; however, they dominated the fossil record throughout the Cretaceous until their ultimate extinction sometime around the K-Pg boundary. Even as stem ant lineages appear to be diverse and abundant throughout the Cretaceous, the extent of their longevity in the fossil record and circumstances contributing to their extinction remain unknown. 3 Here we report the youngest stem ants, preserved in ∼77 Ma Cretaceous amber from North Carolina, which illustrate unexpected morphological stability and lineage persistence in this enigmatic group, rivaling the longevity of contemporary ants. Through phylogenetic reconstruction and morphometric analyses, we find evidence that total taxic turnover in ants was not accompanied by a fundamental morphological shift, in contrast to other analogous stem extinctions such as theropod dinosaurs. While stem taxa showed broad morphological variation, high-density ant morphospace remained relatively constant through the last 100 million years, detailing a parallel, but temporally staggered, evolutionary history of modern and stem ants. [Display omitted] • Youngest-yet (∼77 Ma) stem ant fossils discovered from North Carolina • Stem ant lineages demonstrate comparable generic longevity to crown ants • General ant body plans have remained relatively constant across 100 Ma of evolution • Taxonomic faunal turnover was prolonged across late Mesozoic Sosiak et al. describe the youngest stem ant fossils discovered from late Cretaceous North Carolina amber. Longevity and morphology of the Mesozoic ant assemblage demonstrates total taxic turnover through the late Cretaceous but general ant body plan stability over 100 million years, suggesting parallel but staggered adaptive radiations. [ABSTRACT FROM AUTHOR]

The evolution of large mammal faunas during the Pleistocene of Europe has been widely investigated using taxonomical and/or ecological-functional categories, with special emphasis on the implications for reconstructing hominin dispersal and ecological role. Here, an ecospace modelling approach is for the first time applied to Pleistocene carnivorans of Europe. Examining ecospace occupancy and disparity through time effectively conveys major aspects of faunal dynamics, while offering new insights into species relationships from a trait-space-explicit perspective. Several replacements occurred within-family and concerned species of similar functional role, but between-family competition was also important, especially for hyaenids. When hominins first dispersed into Europe during the Early Pleistocene, carnivorans of middle size that are deemed either highly social active hunters or primarily scavengers were both lacking, a substantial ecospace vacuum that could have been filled by the newcomers. Hominins then became widespread since the Middle Pleistocene, when a decrease of ecospace density is documented. This suggests that adaptability, mainly behavioural for hominins, ecomorphological for other species, might have been key for survival, especially in the more unstable conditions encountered since the latest Early Pleistocene. The uncertainty in categorising the ecology of extinct species is a limitation shared with previous studies, but reducing this multidimensional problem to one ecospace facilitates addressing the main pattern and future assessment. • Ecospace modelling is for the first time applied to Pleistocene carnivorans of Europe. • New insights into species relationships are provided from a trait-space-explicit perspective. • Within-family replacements of species of similar functional role were common. • Hominins may have initially occupied the vacant space of middle-sized and highly social carnivorans. • A Middle Pleistocene drop in ecospace density indicates the key role of adaptability for survival. [ABSTRACT FROM AUTHOR]

The Miocene-Pliocene (Turolian-Ruscinian) transition represents a fundamental interval in the evolution of Euro-Mediterranean paleocommunities. In fact, the paleoenvironmental changes connected with the end of the Messinian salinity crisis are reflected by a major renewal in mammal faunal assemblages. An important bioevent among terrestrial large mammals is the dispersal of the genus Sus, which replaced all other suid species during the Pliocene. Despite its possible paleoecological and biochronological relevance, correlations based on this bioevent are undermined by the supposed persistence of the late surviving late Miocene Propotamochoerus provincialis. However, a recent revision of the type material of this species revealed an admixture with remains of Sus strozzii, an early Pleistocene (Middle Villafranchian to Epivillafranchian) suid, questioning both the diagnosis and chronological range of P. provincialis. Here we review the late Miocene Suidae sample recovered from the Casino Basin (Tuscany, central Italy), whose taxonomic attribution has been controversial over the nearly 150 years since its discovery. Following a comparison with other Miocene, Pliocene, and Pleistocene Eurasian species, the Casino Suidae are assigned to P. provincialis and the species diagnosis is emended. Moreover, it is recognized that all the late Miocene (Turolian) European Propotamochoerus material belongs to P. provincialis and that there is no compelling evidence of the occurrence of this species beyond the Turolian-Ruscinian transition (MN13-MN14). [ABSTRACT FROM AUTHOR]

The highly productive waters of the Humboldt Current System (HCS) host a particular temperate ecosystem within the tropics, whose history is still largely unknown. The Pisco Formation, deposited during Mio-Pliocene times in the Peruvian continental margin has yielded an outstanding collection of coastal-marine fossils, providing an opportunity to understand the genesis of the HCS ecosystem. We present a comprehensive review, completed with new results, that integrates geological and paleontological data from the last 10 My, especially focusing on the southern East Pisco Basin (Sacaco area). We discuss the depositional settings of the Pisco Formation and integrate new U/Pb radiometric ages into the chronostratigraphic framework of the Sacaco sub-basin. The last preserved Pisco sediments at Sacaco were deposited ~ 4.5 Ma, while the overlying Caracoles Formation accumulated from ~ 2.7 Ma onwards. We identified a Pliocene angular unconformity encompassing 1.7 My between these formations, associated with a regional phase of uplift. Local and regional paleoenvironmental indicators suggest that shallow settings influenced by the offshore upwelling of ventilated and warm waters prevailed until the early Pliocene. We present an extensive synthesis of the late Miocene–Pleistocene vertebrate fossil record, which allows for an ecological characterization of the coastal-marine communities, an assessment of biodiversity trends, and changes in coastal-marine lineages in relation to modern HCS faunas. Our synthesis shows that: (i) typical endemic coastal Pisco vertebrates persisted up to ~ 4.5 Ma, (ii) first modern HCS toothed cetaceans appear at ~ 7–6 Ma, coinciding with a decline in genus diversity, and (iii) a vertebrate community closer to the current HCS was only reached after 2.7 Ma. The genesis of the Peruvian coastal ecosystem seems to be driven by a combination of stepwise transformations of the coastal geomorphology related to local tectonic pulses and by a global cooling trend leading to the modern oceanic circulation system. [ABSTRACT FROM AUTHOR]

Cainotheriids are a family of small artiodactyls, known in the fossil record from the late Eocene to the middle Miocene in Western Europe. Contrary to several European endemic ungulate groups that became extinct at the end of the Eocene or close to the Eocene–Oligocene transition (Grande Coupure), cainotheriids crossed this boundary and diversified during the Oligocene. The evolutionary history of cainotheriids around the Grande Coupure remains poorly documented and only a few works deal with the modalities of their evolution, notably because of the scarcity of available Eocene remains. A new fossiliferous karstic network named Dams was discovered during field prospecting in the Quercy area (Tarn-et-Garonne, France). It notably displays two infillings that yielded a great abundance of cainotheriid remains, namely DAM1 (MP19, late Eocene) and DAM3 (MP22, early Oligocene), bracketing the Eocene–Oligocene transition. A detailed study of cainotheriid mandibular and dental remains from these infillings reveals that only Paroxacron valdense occurs at DAM1, while five species are found in DAM3. The karstic network at Dams seemingly records a local taxonomic diversification of cainotheriids after the Grande Coupure, with Cainotheriinae being particularly successful. Our phylogenetic analysis, including cainotheriids from Dams, constitutes the first formal phylogeny of Cainotheriidae. Our results, based on mandibular and dental characters, allow us to (i) clarify relationships within Cainotheriidae, (ii) erect a new family Robiacinidae, as being the sister taxon to Cainotheriidae among Cainotherioidea, and, more broadly, (iii) discuss the controversial position of Cainotheriidae within Artiodactyla, as being more closely related to Ruminantia than to Tylopoda. [ABSTRACT FROM AUTHOR]

We present new species of an enigmatic family of mammals, which is endemic to Europe, the Paroxyclaenidae: Merialus bruneti sp. nov., Fratrodon tresvauxi gen. et sp. nov., Paraspaniella gunnelli gen. et sp. nov., and Sororodon tresvauxae gen. et sp. nov. The fossils described come from six localities of the Ypresian of the Paris Basin (France): Pourcy (MP7), Mutigny, Avenay, Condé-en-Brie (MP8 + 9), Grauves and Prémontré (MP10). They allow the description of three new genera and four new species belonging to the subfamilies Merialinae and Paroxyclaeninae. Two of these new species represent the earliest occurrence of each subfamily. Fossils from Mutigny, Avenay and Condé-en-Brie indicate that merialines were more abundant than paroxyclaenines during the Ypresian. Surprisingly, merialines disappeared from the fossil record at the end of the Ypresian – the youngest records are close to MP10 – while the paroxyclaenines were present in Europe until the end of the middle Eocene. Based on comparison with the data presently available for European mammals during the Ypresian, we suggest the existence of two periods of faunal turnover that must be more extensively studied in the future in order to be fully characterized: the 'Intra-Ypresian Mammal Turnover' and the 'Ypresian–Lutetian Mammal Turnover'. Finally, because the oldest paroxyclaenids appear morphologically closer to cimolestids such as Procerberus than to pantolestans, it is suggested that similarities between paroxyclaenids and pantolestans could be due to convergence. [ABSTRACT FROM AUTHOR]

The present study depends on qualitative and quantitative analyses for the Late Paleocene-Early Eocene benthonic foraminifera at Darb Gaga area, Baris Oasis, Western Desert, Egypt. The study Late Paleocene-Early Eocene succession consists of two rock units; Esna Formation at base and Thebes Formation (lowermost part) at top. Esna Formation is subdivided into four members stratigraphically arranged as follow: El Hanadi, Dababiya Quarry, Darb Gaga and Abu Had. Dababiya Quarry Member (marker of the P/E boundary) is characterized by the occurrence of glauconitic grains at the base confirming a minor hiatus at the P/E boundary. This hiatus led to the missing of the beds no. 1 & 2 of the five beds (lowermost part) of Dababiya Quarry Member. Four benthonic foraminiferal events are defined during the Late Paleocene-Early Eocene interval. The first one is global event at the Paleocene/Eocene (P/E) boundary, and the remainder events are local and define during the Ypresian (Early Eocene). The first event is characterized by a rapid extinction and abrupt faunal changes for the benthonic foraminiferal assemblages. This event led to the extinction of about 80% of the Paleocene foraminiferal taxa. About 72% of these taxa are temporarily extinct and reappeared soon. This event is characterized by carbonate dissolution which suggesting oxygen deficiency of oceanic bottom waters and food supply changes. Afterwards, a recovery phase of the benthonic foraminifers is directly recorded above this event and probably due to improved depositional environmental conditions. Quantitative analyses of benthonic foraminiferal assemblages at Darb Gaga section, suggest an outer shelf paleoenvironmental setting during the deposition of El Hanadi, Dababiya Quarry and Darb Gaga sediments that changes to inner-middle shelf during the deposition of Abu Had Member and inner shelf of Thebes Formation. This succession is subdivided into four depositional sequences which are bracketed by unconformities and their correlative conformities depending on integrated field investigations, lithofacies and biofacies data. These sequences are controlled by sea-level changes and/or tectonic activities that prevailed during the deposition. [ABSTRACT FROM AUTHOR]

Two of the best known Mesozoic marine reptile assemblages can be found in units deposited in the Jurassic Sub-Boreal Seaway of the UK: the late Middle Jurassic Oxford Clay Formation (OCF) and Late Jurassic Kimmeridge Clay Formation (KCF). They record two very differently structured faunas, but understanding the turnover between them is hampered by a gap in the fossil record that spans much of the Oxfordian, the so-called "Corallian gap". We provide a comprehensive review of specimens from the Corallian Group (CG) of the UK, which includes the first descriptions of several fossils, particularly teeth. We demonstrate that there is a severe reduction in observed marine reptile diversity during the Oxfordian, with several Callovian taxa well known from the OCF not persisting into the Corallian strata, including small-to-mid-sized pliosaurids and longirostrine teleosaurids. We do, however, find evidence that at least one member of each key OCF lineage (plesiosauroids, pliosaurids, ichthyosaurs, and thalattosuchians) survived into the Corallian interval, and that one keystone KCF lineage (the Torvoneustes line of metriorhynchid thalattosuchians) was present during this time, indicating an earlier radiation of this group than previously thought. We suggest that faunal turnover between the OCF and KCF may have been driven by environmental perturbations during the Oxfordian, which selectively removed small bodied pliosaurids and longirostrine teleosaurids from the Jurassic Sub-Boreal Seaway, but less affected metriorhynchids, plesiosauroids, and ophthalmosaurid ichthyosaurs. The preferential removal of taxa from the sub-Boreal realm may have helped facilitate the radiation of lineages that became dominant during the Late Jurassic. [ABSTRACT FROM AUTHOR]

Two of the best known Mesozoic marine reptile assemblages can be found in units deposited in the Jurassic Sub- Boreal Seaway of the UK: the late Middle Jurassic Oxford Clay Formation (OCF) and Late Jurassic Kimmeridge Clay Formation (KCF). They record two very differently structured faunas, but understanding the turnover between them is hampered by a gap in the fossil record that spans much of the Oxfordian, the so-called "Corallian gap". We provide a comprehensive review of specimens from the Corallian Group (CG) of the UK, which includes the first descriptions of several fossils, particularly teeth. We demonstrate that there is a severe reduction in observed marine reptile diversity during the Oxfordian, with several Callovian taxa well known from the OCF not persisting into the Corallian strata, including small-to-mid-sized pliosaurids and longirostrine teleosaurids. We do, however, find evidence that at least one member of each key OCF lineage (plesiosauroids, pliosaurids, ichthyosaurs, and thalattosuchians) survived into the Corallian interval, and that one keystone KCF lineage (the Torvoneustes line of metriorhynchid thalattosuchians) was present during this time, indicating an earlier radiation of this group than previously thought. We suggest that faunal turnover between the OCF and KCF may have been driven by environmental perturbations during the Oxfordian, which selectively removed small bodied pliosaurids and longirostrine teleosaurids from the Jurassic Sub-Boreal Seaway, but less affected metriorhynchids, plesiosauroids, and ophthalmosaurid ichthyosaurs. The preferential removal of taxa from the sub-Boreal realm may have helped facilitate the radiation of lineages that became dominant during the Late Jurassic. [ABSTRACT FROM AUTHOR]

The large mammalian fauna of southern Africa is characterised by strong niche separation into grazer and browser species, with few falling into the intermediate mixed-feeder niche. Moreover, the modern fauna is reduced in species diversity compared to the Pleistocene, following the extinction of several specialized grazers in the late Pleistocene and early Holocene. How did this state develop, and how might it be connected to climatic change during the Holocene? To better understand this development, we obtained extensive carbon and oxygen stable light isotope data from herbivore tooth enamel samples from Wonderwerk Cave, South Africa, spanning about 12,000–500 cal. BP. This is a unique dataset since it is the only site in the southern Kalahari with a robust chronometric record and well-preserved faunal remains for the last 12,000 years without significant gaps. Combining the stable isotopes with pollen and micromammal data from Wonderwerk Cave, we have explored shifts in the proportions of C 3 and C 4 plants and moisture availability. Although climate remained generally semi-arid for much of this period, the results show significant hydrological and vegetation shifts in the sequence, particularly with the strengthening of summer rainfall in the mid-Holocene. The results for the sixteen herbivore species reveal a reinforcement of the grazer-browser niche partitioning through the Holocene and shows how niche specialization follows changes in local vegetation composition. In the light of this reconstruction of the local ecology we discuss grazer extinctions, human adaptations, and the drivers behind climatic changes in the summer rainfall zone of southern Africa. [ABSTRACT FROM AUTHOR]

Late Quaternary small mammal faunas document ecological change and biotic responses to past climates but are especially rare in some geographic regions such as the North American Great Plains. Don’s Gooseberry Pit (DGP), a cave in the southeastern Black Hills of South Dakota, USA, contains a fauna documenting small mammal community composition shifts and environmental change over the last 18,000 yr in this data-depauperate region. Although the stratigraphy of the cave appears to be primary, disparate radiocarbon dates indicate that there is mixing of the fauna throughout. A paleoenvironmental signal consistent with regional reconstructions still emerges from an analysis of the stratigraphically ordered fauna. Dated taxa from DGP record the ecological replacement of Dicrostonyx by Myodes and later Microtus in response to late Quaternary warming. Individually dated specimens of Dicrostonyx richardsoni confirm late survival of this cold-adapted taxon in the Black Hills (17,083 cal yr BP). Our results indicate that a coarse paleoecological signal is present in DGP, and that the Black Hills served as a “high-altitude” refugium for cold-adapted species following the end of the last glacial period. [ABSTRACT FROM PUBLISHER]

Two rugose coral superprovinces connected through the Rheic Ocean occurred during the Mississippian-Lower Pennsylvanian: the Palaeotethyan and the North American. They perhaps continued up to the Moscovian, that is until the collision of Gondwana and Laurussia and the appearance of Pangea gave rise to two realms, the Palaeotethyan and the Cordillera–Arctic Uralian. Restricted communication between the superprovinces in the Tournaisian and up to the middle Viséan inclusively resulted in the partial isolation of the North American superprovince from the mainstream of evolution of the rugose corals—i.e., the Palaeotethyan superprovince. Global warming in the late Viséan and the early Serpukhovian led to the opening of the circum-Laurussia continent circulation and allowed eastward migrations of some North American genera to the Palaeotethyan superprovince, though several genera remained endemic. As a result of the patchy distribution of the Serpukhovian and Bashkirian Rugosa, the large Palaeotethyan superprovince was distinctly differentiated in faunal content within domains by, and their response to, the end of the Mississippian faunal turnover. Refugia (such as North African basins), endemic centers of origin (like Akiyoshi Terrane), expanded centers of origin (like the Donets Basin), and domains with mixed roles (such as South China, Ural–Timan–Novaya Zemlya, and western North America) occurred during the late Serpukhovian–early Bashkirian. This differentiation resulted in the local extension of the Mississippian–Pennsylvanian rugose coral turnover to the Homoceras–Hudsonoceras Geozone, mostly towards the end of the Serpukhovian. That important event is best documented so far in the Donets Basin (Ukraine). • Two superprovinces occurred in late Mississippian to Bashkirian rugose corals realm. • Patchy distribution of Rugosa resulted in their deterioration differentiated in time. • Late Viséan warming led to appearance of circum Laurussia current that increased faunal exchange. • Genera created in North American Superprovince widespread thanks to that current. • Refugia of Mississippian Rugosa, fauna creative centers and areas of mixed role are recognized. [ABSTRACT FROM AUTHOR]

ABSTRACT The Late Jurassic to Early Cretaceous interval represents a time of environmental upheaval and cataclysmic events, combined with disruptions to terrestrial and marine ecosystems. Historically, the Jurassic/ Cretaceous ( J/ K) boundary was classified as one of eight mass extinctions. However, more recent research has largely overturned this view, revealing a much more complex pattern of biotic and abiotic dynamics than has previously been appreciated. Here, we present a synthesis of our current knowledge of Late Jurassic-Early Cretaceous events, focusing particularly on events closest to the J/ K boundary. We find evidence for a combination of short-term catastrophic events, large-scale tectonic processes and environmental perturbations, and major clade interactions that led to a seemingly dramatic faunal and ecological turnover in both the marine and terrestrial realms. This is coupled with a great reduction in global biodiversity which might in part be explained by poor sampling. Very few groups appear to have been entirely resilient to this J/ K boundary 'event', which hints at a 'cascade model' of ecosystem changes driving faunal dynamics. Within terrestrial ecosystems, larger, more-specialised organisms, such as saurischian dinosaurs, appear to have suffered the most. Medium-sized tetanuran theropods declined, and were replaced by larger-bodied groups, and basal eusauropods were replaced by neosauropod faunas. The ascent of paravian theropods is emphasised by escalated competition with contemporary pterosaur groups, culminating in the explosive radiation of birds, although the timing of this is obfuscated by biases in sampling. Smaller, more ecologically diverse terrestrial non-archosaurs, such as lissamphibians and mammaliaforms, were comparatively resilient to extinctions, instead documenting the origination of many extant groups around the J/ K boundary. In the marine realm, extinctions were focused on low-latitude, shallow marine shelf-dwelling faunas, corresponding to a significant eustatic sea-level fall in the latest Jurassic. More mobile and ecologically plastic marine groups, such as ichthyosaurs, survived the boundary relatively unscathed. High rates of extinction and turnover in other macropredaceous marine groups, including plesiosaurs, are accompanied by the origin of most major lineages of extant sharks. Groups which occupied both marine and terrestrial ecosystems, including crocodylomorphs, document a selective extinction in shallow marine forms, whereas turtles appear to have diversified. These patterns suggest that different extinction selectivity and ecological processes were operating between marine and terrestrial ecosystems, which were ultimately important in determining the fates of many key groups, as well as the origins of many major extant lineages. We identify a series of potential abiotic candidates for driving these patterns, including multiple bolide impacts, several episodes of flood basalt eruptions, dramatic climate change, and major disruptions to oceanic systems. The J/ K transition therefore, although not a mass extinction, represents an important transitional period in the co-evolutionary history of life on Earth. [ABSTRACT FROM AUTHOR]

An extraordinary sequence of fossiliferous levels at the locality of Gran Dolina in the Atapuerca Hills (Burgos, Spain) records the Early–Middle Pleistocene transition. These levels are well dated by a variety of methods, including palaeomagnetism, which locates Lower–Middle Pleistocene boundary at the top of level TD7. Level TD6 is the type site of the species Homo antecessor and yielded over 90% of the European Early Pleistocene human record, while other levels have an archaeological record. The present paper deals with the earliest Middle Pleistocene ungulates of TD8, but we plan to describe the faunas, or at least the ungulates, of levels TD4 to TD8 in the context of the faunal changes that took place around the Early–Middle Pleistocene transition. About 600 fossils could be assigned to a taxon and on this basis the following ungulates are described from TD8: horse Equus altidens , rhinoceros Stephanorhinus aff. etruscus , wild boar Sus scrofa , hippopotamus Hippopotamus sp., red deer Cervus elaphus , giant deer Eucladoceros aff. giulii , giant deer Megaceroides solilhacus , fallow deer Dama vallonnetensis , and bison Bison voigtstedtensis . The evolution of these taxa is discussed. The fauna from level TD8 dates to the earliest Middle Pleistocene (stage 19) and differs from later faunas in the retention of a small rhinoceros ( Stephanorhinus aff. etruscus ) and the latest representative of the genus Eucladoceros . It differs from earlier faunas in having the striped hyaena. Together with the fauna from TD7, in which the Brunhes–Matuyama boundary is recorded, TD8 will provide the most precise criterions for correlation of the Early–Middle Pleistocene boundary on the basis of fossils of large mammals. Profound changes in the global climate system started to take place during the late Early Pleistocene, leading to intensive environmental and faunal change and to human dispersal into Europe. These events mark the beginning of a new time and the Early–Middle Pleistocene boundary is taken somewhere in the middle of this drawn out process. It is taken at a palaeomagnetic change, which is convenient, but this does not appear to be close to an important climatic or faunal change. Ten faunal events are recognized in the period from about 1.2 to 0.5 Ma. The event closest to the Early–Middle Pleistocene boundary is one of the minor events and up to now it is recorded in only few localities, principally in TD8. [ABSTRACT FROM AUTHOR]

A new cephalopod collection from the Campanian-Maastrichtian boundary interval of NE Mexico, consisting of 1076 individuals assigned to 29 species and 22 genera is presented. This collection is a mix of ammonoids, one coleoid and one nautilid, which originate from at least three ammonoid biozones: The upper Campanian Exiteloceras jenneyi and Nostoceras (Nostoceras) hyatti zones, and the lower Maastrichtian Pachydiscus (Pachydiscus) neubergicus Zone. The age of the collection is thus middle late Campanian to late early Maastrichtian, and it closes a stratigraphic gap between faunas described formerly from this region. The specimens are nuclei collected from the desert pavement. The abundance of specimens allows for a comparison to other Campanian-Maastrichtian ammonoid records from Mexico, North America and Europe. [ABSTRACT FROM AUTHOR]

Well-exposed fossiliferous Upper Cenomanian–Lower Turonian marine sedimentary rocks are present in west-central Jordan. Ammonites serve as an important faunal marker for this interval and can be used to subdivide the Cenomanian–Turonian transition into two upper Cenomanian biozones ( Neolobites vibrayeanus and Vascoceras cauvini ) and two lower Turonian biozones ( Vascoceras proprium and Choffaticeras segne ). A revised stratigraphic range of the Vascoceras cauvini Zone in the study area is proposed, consisting of the Metoicoceras geslinianum and Neocardioceras juddii zones of the standard zonation. Based on intercontinental biostratigraphic correlation, a minor unconformity appears to be present around the Cenomanian–Turonian boundary, and a part of the lower Turonian is probably missing. In addition, a faunal turnover is recorded in the uppermost Cenomanian, marked by the disappearance of most of the Cenomanian taxa, including Costagyra olisiponensis (Sharpe), Ceratostreon flabellatum (Goldfuss), Ilymatogyra africana (Lamarck), Rhynchostreon suborbiculatum (Lamarck), Harpagodes nodosus (Sowerby), and Heterodiadema libycum (Desor). This bioevent is thought to be an effect of the Oceanic Anoxic Event OAE 2; the dramatic shifts in species richness and diversity spanning the Cenomanian–Turonian boundary in the study area occurred in response to the major paleoclimatic and paleoenvironmental perturbations prevailing at that time. The stratigraphic and paleontological patterns studied in Jordan are very similar to those recorded in Egypt in terms of litho- and biostratigraphy, event stratigraphy, and macroinvertebrate content, suggesting the presence of uniform triggering mechanisms and bio-sedimentary responses in the Upper Cretaceous basins of the Middle East and providing clues for a high-resolution correlation between the two areas. [ABSTRACT FROM AUTHOR]

Intensive sampling for vertebrate microfossils has yielded abundant fish remains in the Maastrichtian units of the Tremp Formation (southern Pyrenees, Catalonia, Spain). Samples were taken from eight new sites representing different palaeoenvironments including coastalwetlands and floodplains, in order to assess the fish diversity and to gain a better understanding of the last dinosaur-dominated ecosystems of northeastern Spain. The results suggest that a diverse ichthyofauna inhabited these transitional to inland fluvial settings throughout the Maastrichtian, comprising both marine and freshwater taxa. Three different chondrichthyans, eight basal neopterygians and at least seven teleostean species were found, the latter being more diverse than in other Maastrichtian localities in Europe. Fossil evidence from the studied late Maastrichtian assemblages suggests that teleosteans were present in all the trophic guilds. In addition, the oldest records for osteoglossids and perciforms in Europe, as well as for cypriniforms worldwide, are reported here. The findings from the southern Pyrenees also reveal ichthyofaunal turnover during the Late Cretaceous, with 'holosteans' being replaced by teleosteans. Moreover, Maastrichtian ichthyofaunas fromthe southern Pyrenees showAsian andNorth American biogeographical affinities. [ABSTRACT FROM AUTHOR]

Twenty-nine forest sites in six sampling areas in the Banat region of Romania, adjacent to Serbia, were sampled to obtain inventories of their snail faunas and to make comparisons between these and previously studied faunas in the mountains from the Sudetes in the north-west to the Southern Transylvanian Carpathians in the south. 65 species were recorded overall, with between 13 and 33 at individual sites. Among the six sampling areas that on Schist rock at high altitude differed markedly from the others, and contained mainly species also found in Carpathian forests further north. The remainder, mainly on limestone, also differed among themselves, but contained more species endemic to the region or regions to the south, together with those found mainly in open rocky habitats further north. Some species and subspecies were restricted to particular areas within the region, and although ecological factors accounted for some of these differences, they did not explain all of them. The faunas were differentiated from those in the Carpathians further north, and showed a greater affinity to those from countries to the south. These patterns indicate a transition between northern regions with locally rich but regionally poor forest faunas and those of the Balkans and Mediterranean with many restricted endemics that survived the climatic fluctuations of the Pleistocene in situ. Such faunas are no richer at site level than those from further north, but differ more among themselves even when environmental conditions are similar. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, ●●, ●●-●●. [ABSTRACT FROM AUTHOR]

We present an updated taxonomy and faunal distribution of the micromammal fossil record from the Aragonian and Lower Vallesian of the Calatayud-Montalbán Basin. The analysed record includes the orders Rodentia, Eulipotyphla, and Lagomorpha. The pattern of species turnover shows seven major faunal events, which are correlated with major climate changes based on marine stable oxygen and carbon isotope records. Episodes δ 18 O Mi-2 and Mi-3 are significantly correlated with major micromammal turnover at the boundaries between the Lower and Middle Aragonian and the Middle and Upper Aragonian, respectively. Our results support the existence of a selective turnover during the Aragonian and Lower Vallesian. [ABSTRACT FROM AUTHOR]

Aim: The Messinian salinity crisis (MSC) was an extraordinary geological event that affected the whole Mediterranean region as well as the global marine circulation between 5.97 and c. 5.33 Ma. One of its most direct effects was the emersion of land masses and the subsequent establishment of land bridges that led to common terrestrial faunal exchanges. However, the details of the onset of these exchanges have been a matter of controversy. New findings from southern Iberia of small mammal remains with African similarities have enabled us to review the Messinian faunal exchanges in the Mediterranean region. Location: Mediterranean region. Methods: Small mammal remains with African similarities from two new southern Iberian sites were studied. The small mammal associations of eight Miocene-Pliocene North African sites were also reviewed. Results: Two taxa with African similarities were identified at the Iberian study sites: Debruijnimys almenarensis and a Ruscinomys-like form (cf. Ruscinomys) with a strong spur in the lingual lobe of the anterocone in the M1, a feature observed in North African Ruscinomys and eastern Mediterranean Byzantinia. The taxonomic status of some North African species and/or genera, such as Castillomys, Occitanomys and Prolagus, should be revised according to the new phylogenetic relationships established in European faunas. Main conclusions: Two hypotheses can be proposed for the origin of the African Ruscinomys: (1) among the Iberian Ruscinomys or (2) from the eastern Mediterranean Byzantinia. Our data, currently from only a few, albeit significant, taxa, tend to support an Iberian origin. The discussion presented in this paper suggests an age near the closure of the last Betic Gateway (c. 6.18 Ma) for the first small mammal exchange between Africa and Europe, as well as a single migratory wave of small mammals, filtered by their ecological preferences from this point until the end of the MSC. [ABSTRACT FROM AUTHOR]

The basal portion of the Permian Rio do Rasto Formation (Serrinha Member), Passa Dois Group, Paraná Basin, Brazil, records an entirely new bivalve fauna intercalated between the underlying Pinzonella neotropica assemblage (uppermost portion of the Teresina Formation) and the overlying Leinzia similis assemblage (Rio do Rasto Formation). Mollusks of these assemblages lived in marginal shallow-water habitats of an immense epeiric sea and were dominated by endemic bivalve species. Taxonomic analysis revealed the presence of Terraia curvata (60.61%), Astartellopsis prosoclina (19.70%), Cowperesia emerita (10.61%), Leinzia curta (4.55%), Terraia bipleura (3.03%) and Beurlenella elongatella (1.52%), which are associated with conchostracans and plant remains. Species composition, abundance, and dominance in this novel assemblage differ notably from the preceding ones, suggesting a substantial evolutionary turnover. Regional-scale environmental changes recognized based on taphonomy, facies analysis, and geochemical data consist of progressive freshening of the marginal habitats of the Paraná Basin and taxic changes that include the following: (a) loss of genera, (b) decrease in bivalve abundance and ecological guilds, (c) disappearance of the dominant bivalve group (Pinzonellinae) and (d) diversification of Terrainae bivalves. The ecological signature also changed notably because only infaunal suspension-feeding bivalves are present, indicating a significant loss of functional diversity at the regional scale. Likely stressor factors (among others) are tied to freshening events, suggesting profound changes in (a) salinity, (b) primary productivity and (c) a lack of coarse, stable substrates coupled with high bioturbation rates. Hence, our regional example could offer valuable clues to benthic (bivalve) community responses in a habitat subjected to (a) rapid climate changes and (b) freshening events in shallow-water settings. Finally, the stratigraphic range of the dominant species ( T. curvata ) appears to be restricted to the basal portion of the Rio do Rasto Formation. Based on the presence of this species and of C. emerita , the novel assemblage is tentatively correlated with that of the Permian Gai-As Formation in the Huab region of Namibia, thus supporting previous assumptions of a seaway connecting both basins during the Guadalupian Epoch. [ABSTRACT FROM AUTHOR]

This study deals with the herpetofaunal fossil and subfossil remains from the Cadet 2 site (Marie-Galante, Guadeloupean Archipelago). This study provides new data concerning the herpetofaunal community since the Late Pleistocene by revealing the early local occurrence of some taxa ( Eleutherodactylus sp., cf. Sphaerodactylus sp., Ameiva sp., cf. Capitellum mariagalantae , Anolis cf. ferreus , cf. Antillotyphlops sp., cf. Alsophis sp. and Colubroidea sp. 1) and possible Pleistocene extinctions ( Boa sp. and Colubroidea sp. 2). Moreover, the first metric data for fossil Marie-Galante anoles show clear size stability throughout time. As regards the evolution of the island herpetofaunal biodiversity, our work points to the long-term stability of the fauna before human colonization and subsequently to the marked impact of human-caused environmental disturbances during colonial but also Pre-Columbian periods. [ABSTRACT FROM AUTHOR]

This paper describes and characterises the co-occurrence of ammonite and benthic foraminiferal assemblages across the São Gião outcrop (Central Portugal), a reference section for the Lower-Middle Jurassic boundary in the Lusitanian Basin. The upper Toarcian-lower Aalenian marls and marly-limestones in this section provide a precise and detailed ammonite-based biostratigraphic zonation, with a mixed assemblage of northwest European and Mediterranean faunal elements, associated with benthic foraminifera assemblages with northern hemisphere affinities, both correlatable with the Aalenian GSSP at the Fuentelsaz section (Iberian Cordillera, Spain). A total of 447 well-preserved ammonite specimens and 13.116 foraminifera have been studied; no evidence was detected of any taphonomic processes that could have changed the original assemblages. From a biostratigraphic point of view, the ammonite record has enabled four biostratigraphic units to be recognised (the Mactra and Aalensis subzones of the Aalensis Biozone in the upper Toarcian, and the Opalinum and Comptum subzones of the Opalinum Biozone in the lower Aalenian). With regard to the benthic foraminifera, the taxa identified have enabled the Astacolus dorbignyi Zone and 11 bioevents to be identified, most of which representing local biostratigraphic proxies. However, the increase in the relative abundance of Lenticulina exgaleata Dieni from the upper part of the Opalinum Subzone to the lower part of the Comptum Subzone has a regional value. The constant and continuous ammonite record of northwest European taxa, together with typical Mediterranean taxa – namely Grammoceratinae – throughout the section, the high relative abundance of Miliolina representatives – generally interpreted as foraminifers typical of shallow waters – and the absence of foraminiferal forms typical of cool waters, do not support the inference of cool seawater temperatures attributed to the Early Aalenian, or the global character of the “Comptum cooling event”, at least with reference to the Lusitanian Basin. [ABSTRACT FROM AUTHOR]

Around 88 large vertebrate taxa disappeared from Sahul sometime during the Pleistocene, with the majority of losses (54 taxa) clearly taking place within the last 400,000 years. The largest was the 2.8-ton browsing Diprotodon optatum, whereas the ~100- to 130-kg marsupial lion, Thylacoleo carnifex, the world's most specialized mammalian carnivore, and Varanus priscus, the largest lizard known, were formidable predators. Explanations for these extinctions have centered on climatic change or human activities. Here, we review the evidence and arguments for both. Human involvement in the disappearance of some species remains possible but unproven. Mounting evidence points to the loss of most species before the peopling of Sahul (circa 50–45 ka) and a significant role for climate change in the disappearance of the continent's megafauna. [ABSTRACT FROM AUTHOR]

Abstract: We use newly compiled data on global occurrences of Cretaceous lepidosaurs, mammals and crocodylomorphs, and existing data on dinosaurs, to investigate faunal turnover and fossil record heterogeneity. Statistically significant relationships between many clade-specific fossil record sampling proxies within major continental areas (e.g. European mammal-bearing formations) suggest that temporal patterns of fossil record sampling intensity of the most abundant tetrapod clades are similar to each other, with a few exceptions that might reflect clade-specific facies preferences or differences in worker effort (especially in poorly-sampled regions such as Gondwana). However, the absence of strong statistical relationships between tetrapod sampling proxies from different continental areas suggests that there is no unified ‘global’ sampling signal for terrestrial tetrapods. The Cretaceous witnessed substantial faunal turnover and the rise of many ‘advanced’ clades that today dominate terrestrial faunas. Despite strong spatiotemporal heterogeneity in sampling of the Cretaceous tetrapod record, it is clear that this transition occurred in a spatiotemporally staggered fashion. Thus, it cannot be attributed to a temporally localised early Late Cretaceous (Cenomanian–Turonian) extinction event. Many advanced clades, including eutherian mammals, iguanian and gekkotan squamates, and the main cryptodiran turtle crown clades first appeared, or first attained high fossil diversities, in Asia. However, relatively poor sampling and dating of ‘middle’ Cretaceous terrestrial deposits means that hypotheses of Asian, rather than Laurasian, diversifications remain tentative. Differences between Gondwanan and Laurasian faunas became progressively greater during the Cretaceous, and although many Gondwanan clades survived the end-Cretaceous extinction event, these only survive to the present as relictual populations with narrow geographic ranges (e.g. monotremes and rhynchocephalians). [Copyright &y& Elsevier]

Abstract: The middle Pleistocene fossil mammal assemblage from Lainyamok in the southern Kenya rift has previously been considered the oldest (330–392ka) African mammal community consisting entirely of extant species, with the dominant bovid tentatively attributed to the southern African blesbok (Damaliscus cf. dorcas). We show that the blesbok-like fossils from Lainyamok belong to an extinct species, described here as Damaliscus hypsodon sp. nov. The D. hypsodon hypodigm includes the previously unnamed small alcelaphine material known from late Pleistocene sites elsewhere in Kenya and Tanzania. Its dental anatomy, together with an ecomorphological analysis of its postcrania, indicates that D. hypsodon grazed in open and arid grassland environments. Although Lainyamok is no longer represented entirely by extant species, the absence of species common earlier in the middle Pleistocene of East Africa suggests substantial faunal turnover between 500 and 400ka. Damaliscus hypsodon persisted in East Africa until the end of the Pleistocene and its extinction can be attributed to a loss of arid grassland environments at the onset of the Holocene. The fossil evidence from southern Kenya suggests that the development of the taxonomically modern large mammal community was a long-term process characterized by the extinction of grazing specialists, with marked turnover occurring between ~500 and 400ka and near the end of the Pleistocene. [Copyright &y& Elsevier]

Abstract: Despite a century of paleontological work in Neogene sequences of northwestern Argentina there is still much to learn about the biotic diversity in this area during Pliocene times. We report a rich microvertebrate assemblage recovered from Late Pliocene deposits of Uquía Formation, Jujuy Province, northernmost Argentina. Taxa represented in the studied sample include members of Bufonidae (Amphibia: Anura), Iguanoidea (Reptilia: Squamata), Passeriformes (Aves), Argyrolagidae, Didelphidae, Caviidae, Ctenomyidae, Octodontidae, and Cricetidae (Mammalia). Taphonomic attributes indicate that the bone concentration was produced by owls. The remains were disposed highly concentrated suggesting that the assemblage would have been generated in a short lapse, indicating a low time-averaging, retaining the main ecological signals of the past living community. The studied assemblage is noteworthy because it encompasses at least five new genera of cricetid rodents, illustrating the oldest record in northwestern Argentina for this diverse family of mammals. In spite of clear taxonomic differences at specific and generic levels, the structure of the assemblage is ecologically comparable to modern small mammal communities in terms of body mass distribution, trophic structure and abundance, with a dominance of cricetids over marsupials and caviomorph rodents. Striking differences in taxonomic composition between the Uquian assemblage and the coeval record from central Argentina indicate biogeographical distinctions since the Late Pliocene. The new Uquian cricetids show that the early divergence times for phyllotine genera proposed by several authors cannot be supported. The dominance of phyllotines in the assemblage as well as the record of Microcavia and an octodontid allow inferring arid or semiarid paleoenvironment conditions, in a more or less open habitat. The studied assemblage reflects a noteworthy faunal turnover, which implies the establishment of cricetid rodents as the dominant group in the small mammal communities. This faunal change can be associated to increasing aridity during Late Pliocene worldwide. [Copyright &y& Elsevier]

Abstract: Quantitative radiolarian assemblage analysis has been conducted on middle and upper Eocene sediments (Zones RP16 to RP18) from Ocean Drilling Program Site 1052 in order to establish the radiolarian magnetobiochronology and determine the nature of the faunal turnover across the middle/late Eocene boundary in the western North Atlantic Ocean. We recognize and calibrate forty-five radiolarian bioevents to the magneto- and cyclo-stratigraphy from Site 1052 to enhance the biochronologic resolution for the middle and late Eocene. Our data is compared to sites in the equatorial Pacific (Leg 199) to access the diachrony of biostratigraphic events. Eleven bioevents are good biostratigraphic markers for tropical/subtropical locations (south of 30°N). The primary markers (lowest occurrences of Cryptocarpium azyx and Calocyclas bandyca) which are tropical zonal boundary markers for Zones RP17 and RP18 provide robust biohorizons for correlation and age determination from the low to middle latitudes and between the Atlantic and Pacific Oceans. Some other radiolarian bioevents are highly diachronous (<1million years) between oceanic basins. A significant faunal turnover of radiolarians is recognized within Chron C17n.3n (37.7Ma) where 13 radiolarian species disappear rapidly in less than 100kyr and 4 new species originate. The radiolarian faunal turnover coincides with a major extinction in planktonic foraminifera. We name the turnover phase, the Middle/Late Eocene Turnover (MLET). Assemblage analysis reveals the MLET to be associated with a decrease in low-mid latitude taxa and increase in cosmopolitan taxa and radiolarian accumulation rates. The MLET might be related to increased biological productivity rather than to surface-water cooling. [Copyright &y& Elsevier]

Abstract: The Hippopotaminae rapidly expanded in African habitats by the end of the Miocene. It was previously suggested that this sudden spread, termed the hippopotamine event (HE), was linked to the contemporaneous expansion of grasses with a C4 photosynthetic pathway. C4 plants have been recognised as a major component of late Miocene hippopotamine diets. Conversely, hippopotamids from the earliest Pliocene of Langebaanweg, South Africa, displayed an exclusive C3 diet. Testing the link between the C4 expansion and the HE required documenting the phylogenetic position and the exact diet of these Langebaanweg hippopotamids. Their first anatomical description demonstrates that they were early hippopotamines with a morphology strongly recalling that of the species marking the HE. The analysis of their dental microwear signal indicates that they had a diet dominated by grasses. This illustrates that enamel δ13C values documenting C3 signals alone are inconclusive regarding feeding modes (browsing vs. grazing). It also offers further support to the predominant feeding of early hippopotamines on herbaceous communities, whether dominated by C4 or C3 grasses. Despite a debate on C4 expansion significance, current literature indicates that this signal most likely testifies for late Miocene major changes in Afrotropical vegetation, possibly a dissociation of grassy biome evolution from that of forested biomes notably related to drier conditions and increased grazing pressure. We suggest that these floristic changes triggered the HE in the Afrotropical realm and impacted the subsequent evolution of the family, including at higher latitudes. [Copyright &y& Elsevier]

Two intervals of faunal turnover are revealed by the study of radiolarians from the Early to Middle Miocene sequence of Andaman-Nicobar belonging to Stichocorys wolffii-Calocycletta costata-Dorcadospyris alata zones. These faunal changes are reflected in the values of species diversity, change in abundance of taxa, origination and extinction events and change in radiolarian assemblages. One such faunal change is identified in the latest Early Miocene. The time of this faunal change is marked by the extinction of species like Carpocanopsis cingulata and appearance of Calocycletta costata, Giraffospyris toxaria, Acrocubus octopylus and Liriospyris parkerae, an increasing trend in percentage of cold water species and a decreasing trend in species diversity upwards. The interval coincides with the time of initiation of cooling of sea surface water. Another, and the most prominent faunal turnover of radiolarians is recognized in the Middle Miocene Dorcadospyris alata Zone at about 14.8-12.7 Ma and is characterized by almost complete disappearance of an earlier dominant assemblage and an increase in abundance of an assemblage that was practically absent in the older sequence. The time of this turnover can be correlated with the time of Middle Miocene cooling identified in the examined sequence. [ABSTRACT FROM AUTHOR]

Megalosaurus bucklandii (Dinosauria: Theropoda), the oldest named dinosaur taxon, from the Bathonian (Middle Jurassic) of England, is a valid taxon diagnosed by a unique character combination of the lectotype dentary. Abundant referred material is described and several autapomorphies are identified: ventral surfaces of first and third to fifth sacral centra evenly rounded, ventral surface of second sacral centrum bearing longitudinal, angular ridge; dorsally directed flange around midheight on the scapular blade; an array of posterodorsally inclined grooves on the lateral surface of the median iliac ridge; anteroposteriorly thick ischial apron with an almost flat medial surface; and complementary groove and ridge structures on the articular surfaces between metatarsals II and III. A new phylogenetic analysis focuses on basal tetanurans and includes 41 taxa, six of which have never been included in a cladistic analysis, and 213 characters, 29 of which are new. This is the first phylogenetic analysis to focus on basal tetanuran relationships, and it reveals several new results. Megalosauroidea (= Spinosauroidea) includes two clades, basal to the traditional content of Megalosauridae + Spinosauridae. These comprise Xuanhanosaurus, Marshosaurus, Condorraptor + Piatnitzkysaurus and Chuandongocoelurus + Monolophosaurus. Almost all large-bodied Middle Jurassic theropods are megalosauroids, but Poekilopleuron is an allosauroid. Megalosauroids show geographical differentiation among clades, indicating the development of endemic theropod faunas across Pangaea during the Middle Jurassic. Notably, megalosaurids are not known from outside of Europe during this epoch. Megalosauroids are less diverse and abundant during the Late Jurassic, when most theropods are neotetanurans and allosauroids dominate the large-bodied predator niche. This indicates faunal turnover between the Middle and Late Jurassic. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158, 882–935. [ABSTRACT FROM AUTHOR]

Abstract: The discovery of a rich fauna from the late Miocene Cerro Azul Formation in Caleufú, central Argentina, is reported. This fauna includes vertebrate Holarctic immigrants, among which are the oldest South American records of mammals of the families Cricetidae (Rodentia) and Mustelidae (Carnivora). Stratigraphic, biochronological and taphonomic evidence indicates that the faunal assemblage from Caleufú is confidently synchronous and represents the late Huayquerian (Zone of Xenodontomys elongatus; late Miocene). Thus, this fauna supports hypotheses of the arrival of cricetids and mustelids prior to the Pliocene completion of the Panamanian isthmus. However, the new records do not permit inferences to be made about precise moments of entry of these groups into South America. Representation of the GABI in the fossil record is here interpreted as a major event integrated by a nested pattern of events, including geographically more restricted turnovers (implying particular taphonomic and geographic biases) and associated environmental changes. In such a hierarchical context, the record of Caleufú represents a local turnover different from those occurring with arrivals of these taxa, or their ancestors, into the continent. In accordance with biochronological data, the turnover recorded in Caleufú could be coeval with the global-scale glacial event detected for the late Miocene (ca. 5.7–5.8 Ma). In southern South America, this arid and cold pulse would have triggered the distribution drift to central Argentina of fauna previously restricted to western peri-Andean areas. Local turnovers such as the one reported here, and associated physical changes, have to be analyzed in detail as individual events in order to interpret the chronology, dynamics and paleoenvironmental context of hierarchically greater episodes such as the GABI. [Copyright &y& Elsevier]

Geohistorical records reveal the long-term impacts of climate change on ecosystem structure. A 5-myr record of mammalian faunas from floodplain ecosystems of South Asia shows substantial change in species richness and ecological structure in relation to vegetation change as documented by stable isotopes of C and O from paleosols. Between 8.5 and 6.0 Ma, C4 savannah replaced C3 forest and woodland. Isotopic historical trends for 27 mammalian herbivore species, in combination with ecomorphological data from teeth, show three patterns of response. Most forest frugivores and browsers maintained their dietary habits and disappeared. Other herbivores altered their dietary habits to include increasing amounts of C4 plants and persisted for >1 myr during the vegetation transition. The few lineages that persisted through the vegetation transition show isotopic enrichment of δ13C values overtime. These results are evidence for long-term climatic forcing of vegetation structure and mammalian ecological diversity at the subcontinental scale. [ABSTRACT FROM AUTHOR]

Abstract: The Punung Fauna is a key component in the biostratigraphic sequence of Java. It represents the most significant faunal turnover on the island in the last 1.5 million years, when Stegodon and other archaic mammal species characteristic of earlier Faunal stages were replaced by a fully modern fauna that included rainforest-dependent species such as Pongo pygmaeus (orangutan). Here, we report the first numerical ages for the Punung Fauna obtained by luminescence and uranium-series dating of the fossil-bearing deposits and associated flowstones. The Punung Fauna contained in the dated breccia is of early Last Interglacial age (between 128±15 and 118±3 ka). This result has implications for the age of the preceding Ngandong Fauna, including Homo erectus remains found in the Ngandong Terrace, and for the timing of Homo sapiens arrival in Southeast Asia, in view of claims for a modern human tooth associated with the Punung breccia. [Copyright &y& Elsevier]

Abstract: Continuous Eocene through Oligocene sedimentary sedimentary sections were obtained at Holes 1218A, 1219A, and 1220A drilled during Leg 199 of the Ocean Drilling Program in the central equatorial Pacific. Quantitative analysis of radiolarian assemblages between the upper Eocene through lower Oligocene sedimentary successions revealed that major faunal changes of radiolarians occurred in the late Eocene (35.5–35.7 Ma; Subchron C16n1), around the Eocene/Oligocene boundary (33.7–33.8 Ma; upper Subchron C13r) and in the early Oligocene (30.9–31.3 Ma; uppermost Subchron C12r). The faunal change in the late Eocene is characterized by a stepwise decrease of tropical Eocene species and an increase in cosmopolitan, probably cool-water-tolerant, radiolarians; however, without a significant change in species diversity and radiolarian accumulation rates. The stratigraphic level of this late Eocene turnover came after the late Eocene impact event, and may have been more related to global cooling and associated oceanographic changes than to asteroid impact. The turnover around the Eocene/Oligocene boundary, corresponding to the Oi-1 event, is the most critical during the Eocene–Oligocene transition. Many biotic events such as a sudden drop of species diversity, an increase in the cosmopolitan radiolarian group, a large number of species turnovers, and a drop in radiolarian accumulation rates occurred at or just above this level. Together these indicators suggest a major restructuring of radiolarian assemblages from the high diversity Eocene fauna to a low diversity Oligocene one. The third turnover event within early Oligocene is represented by a replacement of dominant species with a sudden decrease in radiolarian accumulation rates. However, this Oligocene turnover is not consistent with other major δ 18O isotope events, such as Oi-1b and Oi-2. [Copyright &y& Elsevier]

Abstract: The global warming trend of the latest Oligocene was interrupted by several cooling events associated with Antarctic glaciations. These cooling events affected surface water productivity and plankton assemblages. Well-preserved radiolarians were obtained from upper Oligocene to lower Miocene sediments at Ocean Drilling Program (ODP) Leg 199 Sites 1218 and 1219 in the equatorial Pacific, and 110 radiolarian species were identified. Four episodes of significant radiolarian faunal changes were identified: middle late Oligocene (27.5 to 27.3 Ma), latest Oligocene (24.4 Ma), earliest Miocene (23.3 Ma), and middle early Miocene (21.6 Ma). These four episodes approximately coincide with increases and decreases of biogenic silica accumulation rates and increases in δ 18O values coded as “Oi” and “Mi” events. These data indicate that Antarctic glaciations were associated with change of siliceous sedimentation patterns and faunal changes in the equatorial Pacific. Radiolarian fauna was divided into three assemblages based on variations in radiolarian productivity, species richness and the composition of dominant species: a late Oligocene assemblage (27.6 to 24.4 Ma), a transitional assemblage (24.4 to 23.3 Ma) and an early Miocene assemblage (23.3 to 21.2 Ma). The late Oligocene assemblage is characterized by relatively high productivity, low species richness and four dominant species of Tholospyris anthophora, Stichocorys subligata, Lophocyrtis nomas and Lithelius spp. The transitional assemblage represents relatively low values of productivity and species richness, and consists of three dominant species of T. anthophora, S. subligata and L. nomas. The characteristics of the early Miocene assemblage are relatively low productivity, but high species richness. The two dominant species present in this assemblage are T. anthophora and Cyrtocapsella tetrapera. The most significant faunal turnover of radiolarians is marked at the boundary between the transitional/early Miocene assemblages. We also reviewed changes in other microfossil assemblages in the low latitudes during the late Oligocene through early Miocene. The microfossil assemblages of major groups show sequential changes near the Oligocene/Miocene (O/M) boundary (23.8 Ma). Many extinction events and some first occurrences of calcareous nannofossils and many occurrences of radiolarians are found from about 24.8 to 23.3 Ma, and first occurrences of planktic foraminifers and diatoms followed from 23.2 through 22 Ma. Hence, the O/M boundary is identified as a significant level for microfossil evolutions. [Copyright &y& Elsevier]

In this study, we report multiple S-isotopic data (δ34S and Δ33S) of sedimentary pyrite in Early to Late Ordovician sections from South China. The results reveal two distinct groups of negative Δ33S anomalies during the Dapingian and Sandbian to Early Katian stages, which coincide with two faunal turnover events. The negative Δ33S values reflect the mixing of sulfides with strongly negative δ34S and positive Δ33S, and sulfide with strongly positive δ34S and positive Δ33S. This mixing scenario may have resulted from the impinging of deep anoxic waters onto the continental shelves possibly facilitated by sea-level rise. The temporal co-occurrence of negative Δ33S anomalies with intervals of faunal turnover in brachiopod assemblages of South China suggests that the encroachment of anoxic waters may have driven the diversity crises. Our results provide evidence for a dynamic mechanism linking the recurrent upwelling of deep anoxic waters and faunal turnovers during the Early to Late Ordovician. • First multiple S-isotope study of the Ordovician sedimentary rocks from China. • Negative Δ33S values coincide with faunal turnover events. • Upwelling of deep anoxic waters may have driven the diversity crises. • Constrain the dynamics of marine redox variation during the Ordovician. [ABSTRACT FROM AUTHOR]