No evidence for parallel evolution of cursorial limb adaptations among Neogene South American native ungulates (SANUs).

ABSTRACT: During the Neogene, many North American ungulates evolved longer limbs. Presumably, this allowed them to move more efficiently or quickly in open habitats, which became more common during this interval. Evidence suggests that open habitats appeared even earlier in South America, but no study to date has investigated whether the ungulate-like mammals of South America (South American native ungulates or SANUs) evolved similar limb adaptations. We analyzed limb elongation in the two predominant SANU groups, notoungulates and litopterns, by compiling genus-level occurrences from the late Oligocene to the Pleistocene and calculating metatarsal/femur ratio (Mt:F). None of the groups or subgroups we analyzed show a pronounced increase in Mt:F across this interval, with the possible exception of p

SUBMITTER: Croft DA 

PROVIDER: S-EPMC8370646 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature