Widespread loss of mammalian lineage and dietary diversity in the early Oligocene of Afro-Arabia

de Vries, D; Heritage, S; Borths, MR; Sallam, HM; Seiffert, ER

Abstract

Diverse lines of geological and geochemical evidence indicate that the Eocene-Oligocene transition (EOT) marked the onset of a global cooling phase, rapid growth of the Antarctic ice sheet, and a worldwide drop in sea level. Paleontologists have established that shifts in mammalian community structure in Europe and Asia were broadly coincident with these events, but the potential impact of early Oligocene climate change on the mammalian communities of Afro-Arabia has long been unclear. Here we employ dated phylogenies of multiple endemic Afro-Arabian mammal clades (anomaluroid and hystricognath rodents, anthropoid and strepsirrhine primates, and carnivorous hyaenodonts) to investigate lineage diversification and loss since the early Eocene. These analyses provide evidence for widespread mammalian extinction in the early Oligocene of Afro-Arabia, with almost two-thirds of peak late Eocene diversity lost in these clades by ~30 Ma. Using homology-free dental topographic metrics, we further demonstrate that the loss of Afro-Arabian rodent and primate lineages was associated with a major reduction in molar occlusal topographic disparity, suggesting a correlated loss of dietary diversity. These results raise new questions about the relative importance of global versus local influences in shaping the evolutionary trajectories of Afro-Arabia‘s endemic mammals during the Oligocene.

• Journal Article Type: Article
• Acceptance Date: Sep 21, 2021
• Online Publication Date: Oct 7, 2021
• Publication Date: Oct 7, 2021
• Deposit Date: Sep 24, 2021
• Publicly Available Date: Oct 7, 2021
• Journal: Communications Biology
• Print ISSN: 2399-3642
• Electronic ISSN: 2399-3642
• Publisher: Nature Research
• Volume: 4
• Issue: 1
• Pages: 1172
• DOI: https://doi.org/10.1038/s42003-021-02707-9
• Publisher URL: https://doi.org/10.1038/s42003-021-02707-9
• Related Public URLs: https://www.nature.com/commsbio
• Additional Information: Funders : Natural Environment Research Council (NERC);U.S. National Science Foundation;Institute of Museum and Library Services;The Leakey Foundation; Grant Number: NE/T000341/1; Grant Number: BCS-0416164,BCS-0819186,BCS-1231288,BSC-1824745,DBI-1458192,DBI-1612062,DBI-2023087; Grant Number: MA-245704-OMS-20