The genomic basis of convergent evolution in modern sloths (Xenarthra, Mammalia)

ended

At the end of the Pleistocene mass extinctions of the mega-fauna occurred worldwide, in particular in the Americas. Following the last glacial period, mammoths, mastodonts, giant sloths and other large mammals succumbed until extinction (about 10,000 years ago). While some Orders within Mammalia lost a couple of species, the sloths (Folivora, Xenarthra) clade has virtually lost all its diversity, gaining a status of a nearly-extinct suborder. Only two out of the close to 100 genera estimated to have existed survived to the mass extinctions to this date, named Bradypus and Choloepus. In contrast to their giant relatives, the modern sloths are medium-sized animals that developed a very specialized feature: obligatory arboreal suspensory behaviour. Their surprisingly high number of superficial similarities were acquired in parallel – since both genera are completely unrelated, and probably diverged ~30 Mya – and represent an amazing example of convergent evolution. In the current Genomics era, we are finally at a point in which full genomes can be assembled for non-model organisms at reasonable costs, bringing unprecedented opportunities for new studies on elementary questions on evolution. Here we propose to study the genomic signs of convergent evolution leading to obligatory suspensory locomotion and low metabolic rate on a comparative genomic analysis including 4 whole genome sloth sequences, three of which will be sequenced and assembled within this study. The Experienced Researcher masters all the bioinformatics expertise to complete the genomes. The host institution offers all the infrastructure and hypothesis thinking to successfully finalize the project. Jointly this team can push the boundaries of biological knowledge beyond, which will help the applicant to mature in order to lead a research group in the future. The applicant will also be trained in project management, supervision, teaching, and presentation of scientific results.