The inner craniodental anatomy of the Papio specimen U.W. 88-886 from the Early Pleistocene site of Malapa, Gauteng, South Africa

Cercopithecoids represent an essential component of the Plio-Pleistocene faunal assemblage. However, despite the abundance of the cercopithecoid fossil remains in African Plio-Pleistocene deposits, the chronological and geographic contexts from which the modern baboons (i.e. Papio hamadryas ssp.) emerged are still debated. The recently discovered Papio (hamadryas) angusticeps specimen (U.W. 88-886) from the Australopithecus sediba-bearing site of Malapa, Gauteng, South Africa, may represent the first modern baboon occurrence in the fossil record. Given the implication of U.W. 88-886 for the understanding of the papionin evolutionary history and the potential of internal craniodental structures for exploring evolutionary trends in fossil monkey taxa, we use X-ray microtomography to investigate the inner craniodental anatomy of this critical specimen. Our goal is to provide additional evidence to examine the origins of modern baboons. In particular,we explore (i) the tissue proportions and the dentine topographic distribution in dental roots and (ii) the endocranial organization. Consistent with the previous description and metrical analyses of its external cranial morphology, U.W. 88-886 shares internal craniodental anatomy similarities with Plio-Pleistocene and modern Papio, supporting its attribution to Papio (hamadryas) angusticeps. Interestingly, average dentine thickness and distribution in U.W. 88-886 fit more closely to the extinct Papio condition, while the sulcal pattern and relative dentine thickness are more like the extant Papio states. Besides providing additional evidence for characterizing South African fossil papionins, our study sheds new light on the polarity of inner craniodental features in the papionin lineage.Palaeontological Scientific Trust (PAST) Occitanie Region and the French Ministry of Higher Education and ResearchJNC201

Evolution of the melanistic colour in the Alpine salamander Salamandra atra as revealed by a new subspecies from the Venetian Prealps

Bonato L, Steinfartz S. Evolution of the melanistic colour in the Alpine salamander Salamandra atra as revealed by a new subspecies from the Venetian Prealps. Italian Journal of Zoology. 2005;72(3):253-260.In order to reconstruct the evolution of the body colour within the Salamandra atra group, a phylogenetic analysis of the mitochondrial DNA D-loop sequence was performed on seven populations of this group, including all three chromatically different forms and all known nominal subspecies. Also included were four outgroup species. Three major mitochondrial lineages were found within S. atra: G) the invariably yellow-patched S. a. aurorae lineage from the Altopiano dei Sette Comuni (Venetian Prealps); (ii) a genetically distinct lineage represented by a population from the Pasubio massif (Venetian Prealps), in which the yellow patches were either limited or completely lacking; (iii) a lineage comprising all fully melanistic populations from the Alps to the Dinarides, which were assigned to S. a. atra and also included the nominal S. a. prenjensis. Different phylogenetical reconstruction methods and statistical tests supported the hypothesis that the lineage of S. a. aurorae was the sister group to both remaining lineages of S. atra. Within these latter lineages, S. a. pasubiensis emerged as the sister group to all populations of the S. a. atra lineage. This phylogenetic reconstruction suggests that the yellow-patched colour is the ancestral condition in S. atra and the evolutionary transition to fully melanistic colour occurred probably through an intermediate reduction in the extension of the patches. Therefore, the fully melanistic colour of S. lanzai, which is probably not strictly related to S. atra, has an independent origin. The population from the Pasubio massif is here described as Salamandra atra pasubiensis n. subsp

Non invasive conservation genetics of the critically endangered golden-crowned sifaka (Propithecus tattersalli) : high diversity and significant genetic differentiation over a small range

International audienc

Gregarious behaviour in a salamander: attraction to conspecific chemical cues in burrow choice

International audienceGregarious behaviour (i.e. living in groups in contrast to a solitary life) is commonly observed in mammals, but rarely documented in amphibians. Environmental features and/or animal mutual attractions can promote the formation of aggregations that may both reduce the risks of dehydration and predation and increase mate access and fitness. Luschan's salamander (Mertensiella luschani) lives in permanently arid Mediterranean environments; individuals shelter in cracks and crevices and leave only during favourable periods. In this study we examined the role of chemical tracks, in self and conspecific recognition (i.e. gregarious/solitary behaviour), on the social structure of this species. Our results show that juveniles and adults of both sexes use chemical scents deposited on substrate to relocate their shelter. In contrast to numerous other salamander species, Luschan's salamanders also use social information, conveyed by conspecific scents, to identify a safe shelter. Furthermore, this scent marking does not play a role in sexual attraction but allows sex discrimination. This species exhibits gregarious behaviour (i.e. conspecific attraction) as a possible adaptation to dry environments. We discuss both ultimate and proximate factors in the evolution from a solitary to a gregarious life