Nikaido et al. 2003

Nikaido M, Nishihara H, Hukumoto Y, Okada N. 2003. Ancient SINEs from African endemic mammals. Molecular Biology and Evolution 20: 522-527.

These authors discovered a family of Short Interspersed Nuclear Elements (SINEs) restricted to the genomes of Afrotherian mammals. Afrotheria is clade of mammals that originated in Africa during the 60 million years or so it was isolated from the other continents, from approximately 100 to 40 mya, and includes elephants, hyraxes, aardvarks and other mammals. The monophyly of the afrotherian clade is a recent hypothesis, which these authors sought to test by a molecular phylogenetic analysis.

SINEs are not expected to experience horizontal transmission, in contrast to some other retrotransposons, and endemic SINE families have been found in other mammal clades. For example, the Alu family of SINEs are only found in primates.

The main result of this study was the discovery of this family of SINEs and its restriction to animals included in the Afrotheria clade by previous authors based on other data. This result supports the monophyly hypothesis for Afrotheria, and thus helps to connect phylogeny with plate tectonics.