Papers by Stéphane Ducrocq
Neues Jahrbuch für Geologie und Paläontologie - Monatshefte
Neues Jahrbuch für Geologie und Paläontologie - Monatshefte
Neues Jahrbuch für Geologie und Paläontologie - Monatshefte
Neues Jahrbuch für Geologie und Paläontologie - Monatshefte
Paläontologische Zeitschrift, 2016
Journal of anatomy, 2015
Anthracotheres are a fossil family of 'Suiformes' from the Old World, North and Central A... more Anthracotheres are a fossil family of 'Suiformes' from the Old World, North and Central America. They are known from the middle Eocene to the late Pliocene, and are suggested to be the stem group of Hippopotamidae. Yet, their soft anatomy remains poorly known. In this study we describe the virtual endocast of the late Oligocene anthracothere Microbunodon minimum, reconstructed using microtomography, as well as the natural endocast of Merycopotamus medioximus from the late Miocene. These are the first anthracothere endocasts ever described. Particular attention is given to the relative proportions of the brain, the neocortex, the cerebellum and the olfactory bulbs. The…
Comptes Rendus de l'Académie des Sciences - Series IIA - Earth and Planetary Science, 2001
New discoveries of fossil primates from the Asian Palaeogene have led to reconsider the phylogene... more New discoveries of fossil primates from the Asian Palaeogene have led to reconsider the phylogenetical relationships between anthropoid primates from Asia and Africa. The data support a Tarsiidae-Anthropoidea relationship, a sister-group relationship between amphipithecids and propliopithecids, and a weak support for oligopithecid monophyly. Two biogeographical scenarios are proposed from the new phylogenies and are discussed. 2001 Académie des sciences / Éditions scientifiques et médicales Elsevier SAS Primates / Anthropoidea / phylogeny / Asia / Africa Résumé-Les primates paléogènes d'Afrique et d'Asie : nouvelles données phylogénétiques. Les découvertes paléontologiques récentes du Paléogène d'Asie ont conduit à reconsidérer les relations phylogénétiques entre les anthropoïdes d'Asie et d'Afrique. Les données supportent l'hypothèse de relations phylogénétiques étroites entre anthropoïdes et Tarsiidae. Les Amphipithecidae constituent un groupe frère des Propliopithecidae, et la famille des Oligopithecidae est peu solide. Deux scénarios biogéographiques sont déduits des phylogénies proposées et discutés. 2001 Académie des sciences / Éditions scientifiques et médicales Elsevier SAS Primates / Anthropoidea / phylogénie / Asie / Afrique
Journal of Vertebrate Paleontology, 2015
ABSTRACT
Anatomical record (Hoboken, N.J. : 2007), 2013
Previous studies showed that in modern humans the basicranium is formed of two modules: the midli... more Previous studies showed that in modern humans the basicranium is formed of two modules: the midline cranial base and the lateral basicranium which are integrated with the face in very different ways. The study of the relationship between these structures is of prime interest in the context of hominids craniofacial evolutionary history. In this study, we aim to test if the relationship between the midline cranial base and the face on one hand and the lateral basicranium and the face on the other hand are qualitatively and quantitatively different in modern humans and chimpanzees: two phylogenetically close but morphologically different hominids. This work is performed using three-dimensional (3D) landmarks to take into account the face and basicranium 3D shape. Modern humans and chimpanzees both exhibit a significant relationship between lateral basicranium and face, and a nonsignificant relationship between midline cranial base and face. However, the patterns of integration are diff...
Nature Communications, 2015
According to molecular data, hippopotamuses and cetaceans form a clade excluding other extant cet... more According to molecular data, hippopotamuses and cetaceans form a clade excluding other extant cetartiodactyls. Despite a wealth of spectacular specimens documenting cetacean evolution, this relationship remains poorly substantiated by the fossil record. Indeed, the evolutionary path leading from the hippo-cetacean ancestor to Hippopotamidae is plagued by missing fossil data and phylogenetic uncertainties. Only an origination within the extinct anthracotheres is compatible with molecular results, substantial filling of phyletic gaps and recent discoveries of early Miocene hippopotamids. Yet, the anthracothere stock that gave rise to Hippopotamidae has not been identified. Consequently, recent phylogenetic accounts do not properly integrate the anthracotheriid hypothesis, and relate Hippopotamidae to a stretched ghost lineage and/or close to Suina. Here we describe a new anthracothere from Lokone (Kenya) that unambiguously roots the Hippopotamidae into a well-identified group of bothriodontines, the first large mammals to invade Africa. The hippos are deeply anchored into the African Paleogene.
Comptes Rendus de l'Académie des Sciences - Series IIA - Earth and Planetary Science, 1997
Dental remains of the earliest known helohyid artiodactyl are described from the Late Eocene of K... more Dental remains of the earliest known helohyid artiodactyl are described from the Late Eocene of Krabi in South Thailand. This new form, Progenitobyus thailandicus ng. n.sp., is distinct from Go&o&us, a specialized genus from the Middle Eocene of Mongolia, and it displays strong affinities with the primitive anthracotheriid Siamotherium kmbiense from Krabi. Both Thai species certainly testify to an ancestor+iescendant relationship, but an even earlier differentiation of Helohyidae and Anthracotheriidae should be searched for in the Middle Eocene or even earlier.
Journal of Southeast Asian Earth Sciences, 1995
The paleontological study of the mammalian fossils of Tertiary fossiliferous localities from Thai... more The paleontological study of the mammalian fossils of Tertiary fossiliferous localities from Thailand, has led to the description of numerous new taxa, the modification of several extant paleobiogeographical patterns and identification of accurate dates for the Tertiary continental basins. The Krabi Basin yielded 27 distinct mammal species, most of them representing new forms, and an Upper Eocene age is now well established for this southern locality. The use of the Krabi assemblage as a reference fauna also led to the reassessment of the ages of several other Asian localities and suggests that the Thai assemblage lived in a forest under a tropical climate. All localities from northern Thailand occur in a time span ranging from 16 to 14 Ma. The use of the cenogram method, allowed the paleoenvironment of the Neogene Thai localities to be compared with contemporaneous fauna1 communities from the Pakistan Siwaliks and China. The middle Miocene environment in South Asia seems to have been quite open, with a likely monsoonal climate. Finally, the ages of different fossiliferous localities from Thailand are correlated with the geodynamic events following the India-Asia collision.
Comptes Rendus de l'Académie des Sciences - Series IIA - Earth and Planetary Science, 2000
A new genus and species of Anthracobunidae, Hsanotherium parvum, is described from the Middle Eoc... more A new genus and species of Anthracobunidae, Hsanotherium parvum, is described from the Middle Eocene Pondaung Formation in Myanmar. This form is the smallest and the most primitive known in the family, and it suggests that the Eocene South-Asian radiation of Anthracobunidae occurred in a diachronous way on the Indian Subcontinent and eastward. © 2000 Académie des sciences / Éditions scientifiques et médicales Elsevier SAS Mammals / Anthracobunidae / Middle Eocene / Pondaung / Myanmar Résumé-Première découverte d'un Anthracobunidae (Mammalia, ?Tethytheria) dans l'Éocène de la formation de Pondaung, Myanmar. Un nouvel Anthracobunidae, Hsanotherium parvum gen. et sp. nov. de l'Eocène moyen de la Formation de Pondaung au Myanmar est décrit. Cette forme birmane est la plus petite et la plus primitive connue, et suggère que la radiation éocène des Anthracobunidae en Asie du Sud s'est déroulée de manière diachrone sur le sous-continent indien et plus à l'est. © 2000 Académie des sciences / Éditions scientifiques et médicales Elsevier SAS Mammifères / Anthracobunidae / Eocène moyen / Pondaung / Myanmar Version abrégée L'Asie du Sud se caractérise par sa richesse en restes de mammifères primitifs d'âge Éocène inférieur et moyen, témoignant d'un centre d'origine de plusieurs groupes actuels. Les investigations récentes dans la localité de Yarshe Kyitchaung au Myanmar [10, 11, 17] (figure 1) ont livré des restes dentaires pouvant être attribués à un nouvel Anthracobunidae. Cette famille, connue jusqu'à présent uniquement dans l'Éocène d'Inde et du Pakistan [13, 25], a vu son statut controversé [9, 22, 27], mais il est communément admis qu'elle se place au sein des Téthythères [9]. Ordre Tethytheria Mc Kenna, 1975 Famille Anthracobunidae Wells et Gingerich, 1983 Genre Hsanotherium gen. nov. Derivatio nominis. De hsan, mot birman signifiant étrange, et du grec, θgqi'om, animal sauvage. Espèce Type. Hsanotherium parvum sp.nov. Diagnose. Celle de l'espèce. Hsanotherium parvum gen. et sp. nov. Derivatio nominis. En référence à la très petite taille des spécimens.
Zoologica Scripta, 2001
... except the more primitive leptomerycids, hypertragulids and tragulids, there is a weak anteri... more ... except the more primitive leptomerycids, hypertragulids and tragulids, there is a weak anterior cingulid in both Eocene North American ruminants and in ... Thus, the lower dentition of Krabimeryx is close to that of Lophiomeryx, but in the upper molars it significantly differs from that ...
Science, 2001
In the absence of a comprehensive fossil record, the origin and early evolution of Malagasy lemur... more In the absence of a comprehensive fossil record, the origin and early evolution of Malagasy lemurs have been subject to much uncertainty. We report here the discovery of a strepsirrhine fossil with strong cheirogaleid lemur affinities, Bugtilemur mathesoni gen. et sp. nov., from early Oligocene deposits of the Bugti Hills (Balochistan, Pakistan). Bugtilemur represents the earliest record of Lemuriformes, which hence appear to have already diversified outside of Madagascar at least 30 million years ago. This fossil clearly enhances the critical role of the Indian subcontinent in the early diversification of lemurs and constrains paleobiogeographic models of strepsirrhine lemur evolution.
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Papers by Stéphane Ducrocq