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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.

The molluscan fauna inhabiting the algal turfs of mesolittoral rocky outcrops, dominated by the coralline alga Ellisolandia elongata, has been quantitatively analysed in a Marine Protected Area of Málaga, southern Spain (W Mediterranean). A total of 2520 mollusc specimens belonging to 46 species were identified. This taxocenosis was compared to that previously studied from the infralittoral level, where the alga Halopteris scoparia was prevailing and 4084 specimens belonging to 66 species of Mollusca were found. The species Pisinna glabrata, Skeneopsis planorbis, Nodulus spiralis and Tricolia miniata dominated the mesolittoral stage. The occurrence of congeneric species pairs (Tricolia miniata/Tricolia pullus, Nodulus spiralis/Nodulus contortus) which achieve high abundance in one of the levels and are scarce or absent in the other was striking. Therefore, the coralline algal turf in the lower part of the intertidal zone is not just an extension of the “Photophilous Algae” community but a benthic community of its own., Funding for open access charge was provided by Universidad de Granada/CBUA.

The Early Pleistocene was a critical time period in the evolution of eastern African mammal faunas, but fossil assemblages sampling this interval are poorly known from Ethiopia’s Afar Depression. Field work by the Hadar Research Project in the Busidima Formation exposures (~2.7–0.8 Ma) of Hadar in the lower Awash Valley, resulted in the recovery of an earlyHomomaxilla (A.L. 666-1) with associated stone tools and fauna from the Maka’amitalu basin in the 1990s. These assemblages are dated to ~2.35 Ma by the Bouroukie Tuff 3 (BKT-3). Continued work by the Hadar Research Project over the last two decades has greatly expanded the faunal collection. Here, we provide a comprehensive account of the Maka’amitalu large mammals (Artiodactyla, Carnivora, Perissodactyla, Primates, and Proboscidea) and discuss their paleoecological and biochronological significance. The size of the Maka’amitalu assemblage is small compared to those from the Hadar Formation (3.45–2.95 Ma) and Ledi-Geraru (2.8–2.6 Ma) but includes at least 20 taxa. Bovids, suids, andTheropithecusare common in terms of both species richness and abundance, whereas carnivorans, equids, and megaherbivores are rare. While the taxonomic composition of the Maka’amitalu fauna indicates significant species turnover from the Hadar Formation and Ledi-Geraru deposits, turnover seems to have occurred at a constant rate through time as taxonomic dissimilarity between adjacent fossil assemblages is strongly predicted by their age difference. A similar pattern characterizes functional ecological turnover, with only subtle changes in dietary proportions, body size proportions, and bovid abundances across the composite lower Awash sequence. Biochronological comparisons with other sites in eastern Africa suggest that the taxa recovered from the Maka’amitalu are broadly consistent with the reported age of the BKT-3 tuff. Considering the age of BKT-3 and biochronology, a range of 2.4–1.9 Ma is most likely for the faunal assemblage.

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 Palaeoanthropology 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., This work was supported by Ministerio de Ciencia e Innovación, Spain, Grant/Award Numbers: CGL2016-75109-P and CGL2016-80000-P; AGAUR, Gencat, Project number: SGR2017-859; the Palarq Foundation, Spain; the Comunidad Autónoma de la Región de Murcia, Spain, Grant Number: ARQ115/2018 (Subvención para la Investigación e Intervención en el Patrimonio Arqueológico y Paleontológico de la Región de Murcia); and CERCA Programme/Generalitat de Catalunya. The Institut Català de Paleoecologia Humana i Evolució Social (IPHES-CERCA) has received financial support from the Spanish Ministry of Science and Innovation through the ‘María de Maeztu’ program for Units of Excellence (CEX2019-000945-M). DF was supported by a JAE Intro grant (JAEINT_20_0_01073) of the Consejo Superior de Investigaciones Científicas, co-financed by the Museo Nacional de Ciencias Naturales. PP was beneficiary of a postdoctoral fellowship from the ‘María de Maeztu’ program., With funding from the Spanish government through the "Severo Ochoa Center of Excellence" accreditation CEX2019-000945-M.

In fluctuating lake ecosystems, the severity of anthropogenic disturbance is often difficult to assess because the magnitude of natural dynamics rivals or surpasses that of ecosystem alteration due to human impact. Consequently, it is also difficult to evaluate the resilience of these ecosystems' plant and animal communities to that impact. Unfortunately, lake ecosystem response to natural cycles of lake-level and salinity fluctuation at multi-annual time scales is poorly understood, due to complex relationships between hydrological dynamics and the local availability or distribution of ecological niches. We present a 1650-yr-long paleoecological record from Lake Naivasha in Kenya (East Africa) which traces community assembly and turnover in two prominent groups of benthic invertebrates (chironomids and ostracods) in response to a climate-driven sequence of 10 major lake-level fluctuations. Over this time period, lake depth (inferred from sedimentology) fluctuated between similar to 3 and >35 m, and salinity (inferred from fossil diatom assemblages) varied between similar to 100 and similar to 23,500 mu S/cm. Prior to similar to 780 yr ago, the unique community response to salinity was stronger than to lake depth. Around that time the lake transitioned to a more open hydrology, relatively stable freshwater conditions and greater prevalence of macrophyte-associated benthic habitat, so that community response to variations in lake depth (and surface area) became stronger. Notably, major community restructuring in the course of this transition was not synchronous between the two groups, because it depended on the proliferation of key freshwater species in each group. Our results imply that (1) climate-sensitive lake ecosystems are more likely controlled by salinity change if both its amplitude and frequency are large enough to induce ecological species sorting; (2) community response to such salinity changes may be predictable, and likely to show coherence across different groups of aquatic biota; and (3) the timing of major community restructuring strongly depends on the ecology of key species, and whether the species sorting is driven by salinity change itself or indirectly by the salinity-dependent availability of ecological niches.

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 genusSus, 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 MiocenePropotamochoerus provincialis. However, a recent revision of the type material of this species revealed an admixture with remains ofSus strozzii, an early Pleistocene (Middle Villafranchian to Epivillafranchian) suid, questioning both the diagnosis and chronological range ofP. 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 toP. provincialisand the species diagnosis is emended. Moreover, it is recognized that all the late Miocene (Turolian) EuropeanPropotamochoerusmaterial belongs toP. provincialisand that there is no compelling evidence of the occurrence of this species beyond the Turolian-Ruscinian transition (MN13-MN14).

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.

International audience; Bulk sampling of an indurated glauconic sandstone horizon from Djebel el Kébar, Central Tunisia, yielded a moderately diversified assemblage of elasmobranchs (sharks and rays), dating from the late Middle Eocene (mid Bartonian). Here, 10 new taxa (nine new species and three new genera) are described among a total diversity of 33 species. These new taxa highlight the rise of mid-large predator lineages of modern nearshore seas and fill a substantial gap in the sporadic fossil record of the late Middle Eocene. Comparisons of this assemblage with other Middle-Late Eocene faunas from the Tethys seaway indicate that this Tunisian fauna shares more similarities with Late Eocene than with early Middle Eocene assemblages. This suggests that the major shift observed in tropical elasmobranch communities from the Late Eocene, with for instance the appearance of large Carcharhinids replacing Lamniforms, began during the late Middle Eocene. Such a biotic shift could be linked to the warm conditions recorded ca. 41 Ma, known as the Middle Eocene Climatic Optimum (MECO), which was characterized by a short temperature increase of all marine waters.

Even though a handful of long-lived reptilian clades dominated Mesozoic marine ecosystems, several biotic turnovers drastically changed the taxonomic composition of these communities. A seemingly slow paced, within-geological period turnover took place across the Early–Middle Jurassic transition. This turnover saw the demise of early neoichthyosaurians, rhomaleosaurid plesiosaurians and early plesiosauroids in favour of ophthalmosaurid ichthyosaurians and cryptoclidid and pliosaurid plesiosaurians, clades that will dominate the Late Jurassic and, for two of them, the entire Early Cretaceous as well. The fossil record of this turnover is however extremely poor and this change of dominance appears to be spread across the entire middle Toarcian–Bathonian interval. We describe a series of ichthyosaurian and plesiosaurian specimens from successive geological formations in Luxembourg and Belgium that detail the evolution of marine reptile assemblages across the Early–Middle Jurassic transition within a single area, the Belgo–Luxembourgian sub-basin. These fossils reveal the continuing dominance of large rhomaleosaurid plesiosaurians, microcleidid plesiosaurians andTemnodontosaurus-like ichthyosaurians up to the latest Toarcian, indicating that the structuration of the upper tier of Western Europe marine ecosystems remained essentially constant up to the very end of the Early Jurassic. These fossils also suddenly record ophthalmosaurid ichthyosaurians and cryptoclidid plesiosaurians by the early Bajocian. These results from a geographically-restricted area provide a clearer picture of the shape of the marine reptile turnover occurring at the early–Middle Jurassic transition. This event appears restricted to the sole Aalenian stage, reducing the uncertainty of its duration, at least for ichthyosaurians and plesiosaurians, to 4 instead of 14 million years.

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.

Made available in DSpace on 2018-11-26T16:18:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-12-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The basal portion of the Permian Rio do Rasto Formation (Serrinha Member), Passa Dois Group, Parana 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 Parana 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 Gal-As Formation in the Huab region of Namibia, thus supporting previous assumptions of a seaway connecting both basins during the Guadalupian Epoch. (C) 2015 Elsevier Ltd. All rights reserved. Univ Estadual Paulista, Inst Biociencias, Dept Zool, BR-18618970 Botucatu, SP, Brazil Univ Sao Paulo, Programa Posgrad Geoquim & Geotecton, Inst Geociencias, BR-05508080 Sao Paulo, SP, Brazil Univ Sao Paulo, Dept Geol Sedimentar & Ambiental, Inst Geociencias, BR-05508080 Sao Paulo, SP, Brazil Univ Estadual Paulista, Dept Geol Aplicada, Inst Geociencias & Ciencias Exatas, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Dept Zool, BR-18618970 Botucatu, SP, Brazil Univ Estadual Paulista, Dept Geol Aplicada, Inst Geociencias & Ciencias Exatas, BR-13506900 Rio Claro, SP, Brazil FAPESP: 2011/01975-0 CNPq: 500694/92-3 CNPq: 151853/2008-8

Available online 26 November 2015, 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., This research received support from project CGL2012-38434-C03, CGL2012-38358 and CGL-BOS-2012-34717 of the MinECo and the SYNTHESYS Project http://www.synthesys.info/ which is financed by European Community Research Infrastructure Action under the FP7 “Capacities” Program (Synthesys AT-TAF-3663) and from Generalitat de Catalunya2014 SGR 900.

This paper describes and characterises the co-occurrence of ammonite and benthic foraminiferal assemblages across the Sao Giao 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.

The study deals with environmental changes during the Paleocene–Eocene Thermal Maximum (PETM) and its background conditions in Spitsbergen through analysis of benthic foraminiferal assemblages (FA) in a section drilled in the Paleogene Central Basin. The impact of this extreme global warming occurs here in prodelta shelf mudstones composing the lower part of the Gilsonryggen Member (Frysjaodden Formation). The start of the PETM perturbation is marked by a faunal turnover, in which the medium-diversity circumpolar Reticulophragmium assemblage was replaced by a low-diversity Trochammina fauna. During the hyperthermal period, benthic foraminiferal diversity decreased severely, while the dominance of small-sized taxa with epifaunal morphology strongly increased. This low-diversity fauna occurs in sediments with a reduced thorium/uranium ratio (proxy for oxygenation) and kaolinite enrichment (proxy for high humidity). The faunal changes were thus caused by the combined effects of hypoxic and hyposaline conditions in a stratified water column, due to extreme warming with its accompanying intensified hydrologic cycle. The PETM acme coincides with the maximum flooding surface (MFS) of the Gilsonryggen depositional sequence, composed of the Gilsonryggen Member and the overlying Battfjellet and Aspelintoppen formations. The transgressive phase of the sequence was initiated by local tectonics, while the eustatic sea-level rise of the PETM was superimposed on this transgression.To access the supplementary material for this article, please see supplementary files under Article Tools online.

Pterosaurs, a Mesozoic group of flying archosaurs, have become a focal point for debates pertaining to the impact of sampling biases on our reading of the fossil record, as well as the utility of sampling proxies in palaeodiversity reconstructions. The completeness of the pterosaur fossil specimens themselves potentially provides additional information that is not captured in existing sampling proxies, and might shed new light on the group’s evolutionary history. Here we assess the quality of the pterosaur fossil record via a character completeness metric based on the number of phylogenetic characters that can be scored for all known skeletons of 172 valid species, with averaged completeness values calculated for each geological stage. The fossil record of pterosaurs is observed to be strongly influenced by the occurrence and distribution of Lagerstätten. Peaks in completeness correlate with Lagerstätten deposits, and a recovered correlation between completeness and observed diversity is rendered non-significant when Lagerstätten species are excluded. Intervals previously regarded as potential extinction events are shown to lack Lagerstätten and exhibit low completeness values: as such, the apparent low diversity in these intervals might be at least partly the result of poor fossil record quality. A positive correlation between temporal patterns in completeness of Cretaceous pterosaurs and birds further demonstrates the prominent role that Lagerstätten deposits have on the preservation of smaller bodied organisms, contrasting with a lack of correlation with the completeness of large-bodied sauropodomorphs. However, we unexpectedly find a strong correlation between sauropodomorph and pterosaur completeness within the Triassic–Jurassic, but not the Cretaceous, potentially relating to a shared shift in environmental preference and thus preservation style through time. This study highlights the importance of understanding the relationship between various taphonomic controls when correcting for sampling bias, and provides additional evidence for the prominent role of sampling on observed patterns in pterosaur macroevolution.

Background The Belly River Group of southern Alberta is one of the best-sampled Late Cretaceous terrestrial faunal assemblages in the world. This system provides a high-resolution biostratigraphic record of terrestrial vertebrate diversity and faunal turnover, and it has considerable potential to be a model system for testing hypotheses of dinosaur palaeoecological dynamics, including important aspects of palaeoecommunity structure, trophic interactions, and responses to environmental change. Vertebrate fossil microsites (assemblages of small bones and teeth concentrated together over a relatively short time and thought to be representative of community composition) offer an unparalleled dataset to better test these hypotheses by ameliorating problems of sample size, geography, and chronostratigraphic control that hamper other palaeoecological analyses. Here, we assembled a comprehensive relative abundance dataset of microsites sampled from the entire Belly River Group and performed a series of analyses to test the influence of environmental factors on site and taxon clustering, and assess the stability of faunal assemblages both temporally and spatially. We also test the long-held idea that populations of large dinosaur taxa were particularly sensitive to small-scale environmental gradients, such as the paralic (coastal) to alluvial (inland) regimes present within the time-equivalent depositional basin of the upper Oldman and lower Dinosaur Park Formations. Results Palaeoenvironment (i.e. reconstructed environmental conditions, related to relative amount of alluvial, fluvial, and coastal influence in associated sedimentary strata) was found to be strongly associated with clustering of sites by relative-abundance faunal assemblages, particularly in relation to changes in faunal assemblage composition and marine-terrestrial environmental transitions. Palaeogeography/palaeolandscape were moderately associated to site relative abundance assemblage clustering, with depositional setting and time (i.e. vertical position within stratigraphic unit) more weakly associated. Interestingly, while vertebrate relative abundance assemblages as a whole were strongly correlated with these marine-terrestrial transitions, the dinosaur fauna does not appear to be particularly sensitive to them. Conclusions This analysis confirms that depositional setting (i.e. the sediment type/sorting and associated characteristics) has little effect on faunal assemblage composition, in contrast to the effect of changes in the broader palaeoenvironment (e.g. upper vs. lower coastal plain, etc.), with marine-terrestrial transitions driving temporal faunal dynamics within the Belly River Group. The similarity of the dinosaur faunal assemblages between the time-equivalent portions of the Dinosaur Park Formation and Oldman Formation suggests that either these palaeoenvironments are more similar than characterized in the literature, or that the dinosaurs are less sensitive to variation in palaeoenvironment than has often been suggested. A lack of sensitivity to subtle environmental gradients casts doubt on these forces acting as a driver of putative endemism of dinosaur populations in the Late Cretaceous of North America. Electronic supplementary material The online version of this article (doi:10.1186/s12898-016-0106-8) contains supplementary material, which is available to authorized users.

[EN] 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 δ18O 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., [FR] Ce travail actualise la taxonomie et la distribution faunique du registre fossile des petits mammifères du bassin de Calatayud-Montalbán de l’Aragonien au Vallésien inférieur. Les ordres Rodentia, Eulipothyphla et Lagomorpha sont inclus dans l’étude. Le modèle de renouvellement faunique est analysé et expliqué en relation avec les changements climatiques globaux. Sept événements fauniques principaux ont été reconnus et corrélés aux changements climatiques majeurs, grâce aux enregistrements isotopiques marins (oxygène et carbone). Les événements δ18O Mi-2 et Mi-3 sont significativement corrélés aux renouvellements fauniques qui touchent les micromammifères, respectivement aux limites de l’Aragonien inférieur/moyen et moyen/terminal. La présente analyse corrobore l’existence d’un renouvellement faunique sélectif au cours de l’Aragonien et du Vallésien inférieur., The Spanish MICINN/MINECO projects CGL2004-02094/BTE, CGL2007- 65208, CGL2008-04200/BTE; CGL2011-28877 support this study.

International audience; 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 C.(4) photosynthetic pathway. C(4) 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 C(3) diet. Testing the link between the C(4) 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 delta(I3)C values documenting C(3) 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 C(4) or C(3) grasses. Despite a debate on C(4) 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.

A new ammonite biozonal scheme is proposed for the Upper Barremian of southeastern France. It takes into account faunal changes, sequence stratigraphy and historical data. Four new biohorizons are proposed. At present, three (formerly six) are accepted for the Upper Barremian: the Vandenheckei, Sartousiana and Giraudi biozones. The first contains three subzones, the Uhligi (current status discussed), the Sayni and the Barremense subzones, and two new biohorizons, the Marchandi and Breistrofferi biohorizons (top of the Barremense Subzone). The Sartousiana Biozone now includes the Limentinus, Provincialis and Feraudianus subzones. This last one lost its status of biozone because of paleontologic and stratigraphic arguments. Six biohorizons are recognized in the Sartousiana Biozone: the Limentinus, Provincialis, Casanovai, Feraudianus, Magnini and Autrani biohorizons. The Giraudi Biozone includes the Giraudi, Sarasini and Waagenoides subzones and the Giraudi, Emerici and Puzosianum biohorizons.

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.

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.

International audience; 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 maria-galantae, 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.; Nous étudions ici le matériel herpétofaunistique provenant du site de Cadet 2, situé surl’île de Marie-Galante, dans l’archipel de la Guadeloupe. L’analyse de ces restes apporte desdonnées inédites concernant le peuplement herpétologique de l’île depuis le Pléistocènesupérieur. Elle met en évidence la présence ancienne de certains taxons sur l’île (Eleuthero-dactylus sp., cf. Sphaerodactylus sp., Ameiva sp., cf. Capitellum mariagalantae, Anolis cf. ferreus,cf. Antillotyphlops sp., cf. Alsophis sp. et Colubroidea sp. 1). Elle montre aussi de possiblesextinctions datant du Pléistocène (Boa sp. et Colubroidea sp. 2). Nos premiers résultats obtenus sur les faibles variations de la taille des anolis fossiles de Marie-Galante démontrentla grande stabilité des peuplements au cours du temps. Ce travail met en avant la stabilitéde l’herpétofaune de l’île durant les périodes précédant l’arrivée de l’homme, puis les mod-ifications considérables qui suivent son installation pendant les périodes précolombiennes,puis modernes.

The study deals with environmental changes during the Paleocene-Eocene Thermal Maximum (PETM) and its background conditions in Spitsbergen through analysis of benthic foraminiferal assemblages (FA) in a section drilled in the Paleogene Central Basin. The impact of this extreme global warming occurs here in prodelta shelf mudstones composing the lower part of the Gilsonryggen Member (Frysjaodden Formation). The start of the PETM perturbation is marked by a faunal turnover, in which the medium-diversity circumpolar Reticulophragmium assemblage was replaced by a low-diversity Trochammina fauna. During the hyperthermal period, benthic foraminiferal diversity decreased severely, while the dominance of small-sized taxa with epifaunal morphology strongly increased. This low-diversity fauna occurs in sediments with a reduced thorium/uranium ratio (proxy for oxygenation) and kaolinite enrichment (proxy for high humidity). The faunal changes were thus caused by the combined effects of hypoxic and hyposaline conditions in a stratified water column, due to extreme warming with its accompanying intensified hydrologic cycle. The PETM acme coincides with the maximum flooding surface (MFS) of the Gilsonryggen depositional sequence, composed of the Gilsonryggen Member and the overlying Battfjellet and Aspelintoppen formations. The transgressive phase of the sequence was initiated by local tectonics, while the eustatic sea-level rise of the PETM was superimposed on this transgression. Keywords: PETM; foraminifera; faunal turnover; diversity decrease; sequence stratigraphy (Published: 25 July 2013) To access the supplementary material for this article, please see Supplementary files in the column to the right (under Article Tools) Citation: Polar Research 2013, 32 , 19737, http://dx.doi.org/10.3402/polar.v32i0.19737

The Namurungule Formation yields a large amount of mammals of a formerly unknown and diversified vertebrate assemblage of the late Miocene. The Namurungule Formation has been dated as approximately 7 to 10 Ma. This age agrees with the mammalian assemblage of the Namurungule Formation. Sedimentological evidence of this formation supports that the Namurungule Formation was deposited in lacustrine and/or fluvial environments. Numerous equid and bovid remains were found form the Namurungule Formation. These taxa indicate the open woodland to savanna environments. Assemblage of the Namurungule Fauna indicates a close similarity to those of North Africa, Southwest and Central Europe, and some similarity to Sub-Paratethys, Siwaliks and East Asia faunas. The Namurungule Fauna was the richest among late Miocene (Turolian) Sub-Saharan faunas. From an analysis of Neogene East Africa faunas, it became clear that mammalian faunal assemblage drastically has changed from woodland fauna to openland fauna during Astaracian to Turolian. The Namurungule Fauna is the forerunner of the modern Sub-Saharan (Ethiopian) faunas in savanna and woodland environments.