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Summary: The Equidae have a long evolutionary history that has interested palaeontologists for a long time. Their morphology-based taxonomy, however, is a matter of controversy. Since most equid species are now extinct, the phylogenetic tree based on genetic data can be established only imperfectly via deduction of present day genomes and little is known about the past genetic diversity of these species. Recent studies of ancient DNA preserved in fossil bones have led to a simplification of the phylogenetic tree and the classification system. The situation is still particularly unclear for the wild asses whose geographical distribution in the Pleistocene and the early Holocene stretched from Northern Africa to Eurasia before they became endangered or extinct. Therefore, we performed a phylogeographic study of bone remains of wild asses covering their former geographic range over the past 100,000 years based on the analysis of ancient mitochondrial DNA. Here, we will not show but rather discuss our results calling the morphology-based classification into question and indicating that morphological criteria alone can be an unreliable index in inferring various equid species. Indeed, the diversity of mitochondrial lineages in populations with similar morphology along with genetic signatures shared between morphologically distinct animals reveal a significant morphological plasticity among Equus species. The classification of palaeontological species based on morphological and genetic criteria will be discussed. [ABSTRACT FROM AUTHOR]

Northwestern Africa is today characterized by high geographical, climatic and ecological diversity; it is recognized as a hotspot of biodiversity and a major area for both human and faunal evolution. Studies of North African fossil microvertebrates have increased considerably in recent years, but they no longer just provide palaeontological descriptions of the species found in the assemblages. They also aim at better understanding the evolution of faunal communities in relation to Quaternary climate changes and at reconstructing the palaeoenvironmental background of prehistoric human occupations, in well-established taphonomic and chronological contexts. These studies are also increasingly adopting an integrative approach by combining archaeology, palaeontology, (palaeo)genetics, taphonomy, palaeoecology and systematics, and using new methods such as geometric morphometrics and isotopic analyses on both fossil and modern specimens. This paper aims to present a history of the studies on Quaternary terrestrial microvertebrates from northwestern Africa, and show how recent multidisciplinary studies have provided new perspectives and evidence on the respective influences of climate change and increasing human pressure on their evolution. • This paper brings an updated state-of-the-art on Quaternary North African microvertebrate studies. • We highlight the interest of combining data from different disciplines (integrative approach). • We especially explore the role of environmental and anthropogenic changes on the microvertebrate biodiversity in Morocco. [ABSTRACT FROM AUTHOR]