The North American «Hipparion Datum and implications for the Neogene of the Old World

A large sample of skulls and associated dentitions of Cormohipparion sphenodus (Cope, 1889). new combination, is described from Miocene deposits of Nebraska, Colorado, New Mexico, and California. This species is morphologically more advanced than the most primitive species of the genus, C. goorisiMacFadden & Skinner, 1981, and more primitive than a third and more advanced species of this genus. C. occidentale (Leidy, 1856). In several characters such as configuration of the preobrital fossa, size, hypsodonty, shape of protocone, and complexity of enamel plication, C. sphenodus is morphologically similar, and potentially related to, some Old World Vallesian «Hipparion. In addition, based on radiometric calibration of stratigraphic sequences in Nebraska and California, C. sphenodus spans an interval of time from about 13.6 to 11 Ma. Inasmuch as the Old World «Hipparion Datum is calibrated at about 12 Ma, we conclude that C. sphenodus exhibits the morphological and chronological prerequisites to have been directly ancestral to some of these Old World forms.The hipparion horses apparently were a polyphyletic assemblage of several genera, and their biogeographic and biochronologic history is more complex than classically thought. Several dispersal events involving these horses may have occurred between the New and Old Worlds during the late Miocene.     

Additions a la faune de sélaciens fossilesdu Maroc: 1: Sur la présence des genres Heptranchias,Alopias etOdontorhytis dans l'Yprésien des Ouled Abdoun

Recent researches in the phosphat-bearing basins ofMorocco have allowed to collect new selachian forms. In this paper, three Ypresian genera from Ouled Abdoun basin, new for Morocco, are described: Heptranchias howellii (Reed, 1946), Alopias denticulatus nov. sp. and Odontorhytis pappenheimiBöhm, 1926. The re-discovery of the genus Odontorhytis allows to state precisely its morphological dental features and to affirm that it is well a selachian and not a teleostean, as it was thought. The stratigraphic distribution of some species is stated precisely.     

On the ecological scenario of the first hominin dispersal out of Africa

The archaeopaleontological site of Dmanisi in Georgia, dated to ～1.8 Ma, provides evidence on the first hominin dispersal out of Africa, while the sites of Barranco León and Fuente Nueva-3 in Spain, dated to ～1.4 Ma, record the earliest hominin settlements in Europe. However, a number of issues related to the dispersal route, the climatic conditions and the ecological scenario of this dispersal event are subject to debate. In a recent paper in L’anthropologie, Agustí and Lordkipanidze (2019) proposed an alternative scenario for the arrival of hominins in the Caucasus, which they conceived as a forest refugium area during the Early Pleistocene, and discarded that their dispersal coincided with that of other members of the Ethiopian and Asian faunas, like the sabertooth Megantereon whitei or the giant hyena Pachycrocuta brevirostris. Our review of these issues suggests that: (i) the elongated sabers and reduced postcanine teeth of African M. whitei limited the ability of this predator to process the prey carcass, which resulted in scavengeable resources for the Dmanisi hominins; (ii) the mass estimate in excess of 100 kg obtained for the trochlear perimeter of the distal humerus of the hyena from Dmanisi shows that it can be confidently ascribed to the genus Pachycrocuta; (iii) the postcranial anatomy of the Dmanisi hominins was not advantageous for scavenging tree-stored prey; (iv) the laterally flattened upper canines of M. whitei could not withstand the loads that would result from climbing a prey carcass into a tree; (v) paleobotanical analyses suggest a temperate grassland ecosystem in Dmanisi, not dominant forest conditions, with enhanced aridity in the level of hominin occupation; (vi) similarly, the low frequency of arboreal pollen in the Levantine Corridor at ～1.8 Ma points to more arid conditions than today in this area; (vii) many archaeopaleontological sites of the Rift Valley and its extension towards the Red Sea, the Levant and the Caucasus show evidence of tectonic, volcanic and/or hydrothermal events; and (viii) the delay of 400 ka in the arrival of hominins in Western Europe did not result from a lower availability of scavengeable resources.     

Les néandertaliens de la Caverna delle Fate (Finale Ligure,Italie). II – Les dents

The neandertalian remains discovered in the Caverna delle Fate, Finale Ligure (Italy) gave up a majority of dental material: 10 isolated teeth and six teeth upon arcade or included in the adult mandible Fate 3 and in the child mandible 8–10 years old, Fate 2. Until now, this assemblage is the most numerous of neandertalian teeth excavated in Italy, with archeostratigraphic and paleoenvironmental accurate context. No decidual tooth, lost naturally, has been recognized. The dental material is well preserved, not much altered by wear. The morphometric data confirm the possibility of presence of a gracile neandertalian population living along the mediterranean septentrional European shore. These populations were present since the MIS 5.1, between 80,000 and 70,000 years. This gracility can be explained by the geographic impact and not by the evolutive stage.     

Microevolution of outer and inner structures of upper molars in Late Pleistocene and Early Holocene humans

In this study, we investigate outer and inner variations of upper second molars (UM2) for Late Pleistocene and Early Holocene modern humans, at a key-period in our evolutionary history associated with major sociocultural, economic and environmental changes. Non-metric traits have been recorded on 89 UM2 of 66 Upper Paleolithic, Mesolithic and Neolithic individuals, and 40 UM2 have been microscanned to assess variations in enamel thickness (ET) distribution and enamel–dentine junction (EDJ) shape. Major changes are found between Mesolithic and Neolithic periods: a decrease of the metacone expression combined with an increase of the hypocone development; an increase of the heterogeneity of ET distribution between lingual and buccal cusps; and an increase of the development of the dentine horn tips corresponding to the hypocone and, to a lesser extent, to the metacone. These morphological modifications could be linked to the masticatory functional changes associated with the transition to agriculture.     

A new genus (Chardinomys) of murid rodent (Mammalia,Rodentia) from the neogene of China,and comments on its biogeography

Three murid specimens from the late Neogene ofChina are described, one as the new taxon Chardinomys, which is most closely related to Orientalomys. The Orientalomys-Chardinomys complex was widely distributed over the Palearctic region during the late Neogene. Cf. Rattus occurring with the Orientalomys-Chardinomys complex in China suggests South Asian influence in the eastern Palearctic during the late Neogene.     

A new crocodylomorph tooth assemblage from the Tataouine Basin and comments on the stratigraphic context of the Douiret Formation

A new crocodylomorph tooth assemblage from the Lower Member of the Douiret Formation (uppermost Jurassic–lowermost Cretaceous) in southeastern Tunisia is described. These teeth have been grouped into five morphotypes based on their diagnostic morphological features. The sample includes teeth, which have not been reported until now, such as non-Machimosaurini teleosauroid teeth, and labiolingually compressed tooth crowns with cutting edges devoid of serrations. Certain minor morphometric differences have been interpreted as ontogenetic or being possibly related to the position of the teeth in the jaws. Three trophic entities have subsequently been defined on the basis of the morphological characteristics of the teeth, and a possible niche partitioning between at least three crocodylomorph taxa is highlighted for the first time in the Tataouine Basin. On the other hand, the stratigraphic context of the Douiret Formation is thoroughly discussed in order to show how stratigraphic uncertainties could significantly impact previous attempts at reconstructing the macroevolutionary history of Crocodylomorpha. The latter should be treated with caution when the stratigraphic context of the fossil bearing formation remains a subject of debate.     

Dicerorhinus miguelcrus afonti nov. sp., une nouvelle espèce de rhinocéros (Mammalia,Perissodactyla) du gisement pliocène supérieur de Layna (Soria,Espagne) et de la formation pliocène de Perpignan (Pyrénées-Orientales,France)

More than 90 remains of rhinoceroses bones and teeth have been recovered from the Layna Pliocene deposit. They correspond to a middle sized animal with stout bones and is quite different from both the large sized Pliocène D. megarhinus, the lower Villafranchian D. jeanvireti and the slim small Villafranchian D. etruscus. Its a new species belonging to the Dicerorhinus genus: D. miguelcrusafonti nov. sp. This species is also found in the Perpignan Pliocene formation, together with D. megarhinus.