Abstract

The Afar Triangle in easternmost Africa is one of biogeographically important regions, whose recent biota is virtually unknown. Here we evaluated the level of evolutionary uniqueness of biodiversity of this region in a wide regional and continental biogeographical context, using rodents as a model group. By combining our recent collections with historical records, and based on genetic data and phylogenetic approaches, we specifcally tested whether and to what extent the geographical isolation of the Afar Depression is refected in allopatric diversifcation of arid-adapted mammals. We documented the presence of 16 rodent species (four are reported for the frst time in Ethiopia and one rediscovered there after more than 100 years) and eight additional species are likely present based on literature data. Comparative phylogeographic analysis suggests that the Afar Triangle can be considered as a part of a larger Somalian biogeographical region, but its fauna is genetically distinct, including the presence of narrow Afar endemics. To a lesser extent, there are taxa with evolutionary afnities to the eastern Sahara–Sahelian region and to the southern Arabian Peninsula. Compared to the Ethiopian Highlands, the rodent fauna of Afar is relatively poor. However, similarly to highlands, the evolutionary distinctiveness of mammals in the Afar Triangle is very high and it can be considered a unique centre of endemism. Our frst comprehensive summary of Afar rodents signifcantly flls the gap in the knowledge of the mammalian fauna of arid regions in Ethiopia and the Horn of Africa in general and highlights the signifcance of the region for nature conservation.

Keywords

Arid region; DNA barcoding; Gerbils; Phylogeography; Somali-Masai savanna

Published in

Biodiversity and Conservation
2022, Volume: 31, number: 2, pages: 629-650

UKÄ Subject classification

Ecology


Publication identifier

DOI: https://doi.org/10.1007/s10531-022-02354-4

Permanent link to this page (URI)

https://res.slu.se/id/publ/120472