The study of speciation processes occurring at the Pliocene-Pleistocene boundary in individual groups of mammals in the Horn of Africa allows us to reconstruct the picture of the evolution of biological diversity in poorly studied parts of the world. The study Phylogeny, biogeography, and integrative taxonomic revision of the Afro-Arabian rodent genus Ochromyscus (Muridae: Murinae: Praomyini) published in the Zoological journal of the Linnean Society examined in detail rodents of the genus Ochromyscus inhabiting the Horn of Africa, as well as the southeastern part of the Arabian Peninsula. Scientists from the Laboratory of Mammalian Microevolution of the A.N. Severtsov Institute of Ecology and Evolution (IEE RAS, Moscow) took part in the work – Ph.D. Kostin D.S. and Doctor of Biological Sciences Lavrenchenko L.A.
Using both genetic and morphological data, three species were identified within the genus: two in East Africa (O. brockmani and O. niveiventris) and one in South Arabia (O. yemeni). Despite their morphological similarities, it was shown that the separation of all three species from a common ancestor occurred by the middle of the Pliocene (3.5 million years ago). At the same time, the separation of species inhabiting East Africa occurred earlier, and the colonization of the Arabian Peninsula apparently occurred later, due to the presence of a relatively recent continental bridge, or the past presence of the genus along the eastern coast of the Red Sea and subsequent spread through the Sinai Peninsula. Subsequently, the disappearance of the land bridge between Africa and the Arabian Peninsula led to the isolation of the Arabian population into a separate species - O. yemeni.
The work was supported by a grant from the Russian Science Foundation.
The work was published in the journal Zoological Journal: Yonas Meheretu, Ondřej Mikula, Daniel Frynta, Petra Frýdlová, Getachew Mulualem, Leonid A Lavrenchenko, Danila S Kostin, Hassan Sh Abdirahman Elmi, Radim Šumbera, Josef Bryja Phylogeny, biogeography, and integrative taxonomic revision of the Afro-Arabian rodent genus Ochromyscus (Muridae: Murinae: Praomyini), Zoological Journal of the Linnean Society, Volume 202, Issue 1, September 2024.