Russian scientists have determined the phylogenetic position of Ammodila, a species that is one of the last few unsolved mysteries in the fauna of African rodents. The species was described by the British zoologist Edward D'Winton in 1898 as a member of the Gerbillinae subfamily, but due to the lack of modern material suitable for molecular genetic analysis, its phylogenetic position on the evolutionary tree of gerbils has remained unknown up to the present day.
Joint work of scientists from the A.N. Severtsov Institute of Ecology and Evolution RAS (Moscow) and the Zoological Museum of Moscow State University (Moscow), performed by sequencing the sequences of mitochondrial and nuclear genes from a specimen caught in Ethiopia, showed that Ammodilus is a taxon sister to all living members of the Gerbillinae subfamily.
Using paleontological data to date the phylogenetic tree, it was possible to establish that the separation of the evolutionary line of Ammodila from other groups of gerbils occurred at the border of the middle and late Miocene, about 11.7 million years ago. Despite such an ancient age of isolation, Ammodilus is by no means a “living fossil”, since it has a number of rather progressive morphological features. To describe the phenomenon in which the evolutionary line, throughout its history, does not experience further branching, the term "Ancient loner" was proposed.
The results obtained support the assumption of an African origin of the subfamily, although the question of whether these were the vast territories of the Horn of Africa, or whether the areas lying in northern Africa should be considered the cradle of the gerbils, remains open.
The results of the study were supported by grants from the Russian Foundation for Basic Research and the Russian Science Foundation and published in the journal Zoologica Scripta.
Kostin, D. S., Martynov, A. A., Lebedev, V. S., Zemlemerova, E. D., Gromov, A. R., & Lavrenchenko, L. A. (2022). Position of the ammodile and the origin of Gerbillinae (Rodentia): Out of the Horn of Africa? Zoologica Scripta, 51(5), 522-532.
Ministry of Education and Science: ""Ancient loner": scientists have established when ammodilus separated from other groups of gerbils"
RAS: ""Ancient loner": when ammodilus separated from other groups of gerbils"
Scientific Russia: "Scientists have established when ammodilus separated from other groups of gerbils"
Ministry of Education and Science: ""Ancient loner": scientists have found a rodent whose evolutionary line has not been divided for 11.7 million years"