Palaeoproteomics resolves sloth relationships

PRESSLEE, SAMANTHA; SLATER, GRAHAM J.; PUJOS, FRANÇOIS; FORASIEPI, ANALÍA M.; FISCHER, ROMAN; MOLLOY, KELLY; MACKIE, MEAGHAN; OLSEN, JESPER V.; KRAMARZ, ALEJANDRO; TAGLIORETTI, MATÍAS; SCAGLIA, FERNANDO; LEZCANO, MAXIMILIANO; LANATA, JOSÉ LUIS; SOUTHON, JOHN; FERANEC, ROBERT; BLOCH, JONATHAN; HAJDUK, ADAM; MARTIN, FABIANA M.; SALAS GISMONDI, RODOLFO; REGUERO, MARCELO; DE MUIZON, CHRISTIAN; GREENWOOD, ALEX; CHAIT, BRIAN T.; PENKMAN, KIRSTY; COLLINS, MATTHEW; MACPHEE, ROSS D. E.

Nature Ecology & Evolution

Nature Publishing Group

Lugar: London; Año: 2019

The living tree sloths Choloepus and Bradypus arethe only remaining members of Folivora, a major xenarthran radiation that  occupied a wide range of habitats in manyparts of the western hemisphere during the Cenozoic, including both continentsand  the West Indies. Ancient DNAevidence has played only a minor role in folivoran systematics, as most slothslived in places not  conducive to genomicpreservation. Here we utilize collagen sequence information, both separatelyand in combination with  publishedmitochondrial DNA evidence, to assess the relationships of tree sloths andtheir extinct relatives. Results from phylogenetic analysis of these datasetsdiffer substantially from morphology-based concepts: Choloepus groups withMylodontidae,  not Megalonychidae; Bradypusand Megalonyx pair together as megatherioids, while monophyletic Antilleansloths may be  sister to all otherfolivorans. Divergence estimates are consistent with fossil evidence formid-Cenozoic presence of sloths in  theWest Indies and an early Miocene radiation in South America.