Body mass estimation in Early Miocene native South American ungulates: a predictive equation based on 3D landmarks

摘要: South American native ungulates include extinct taxa that evolved within the geographical context given by isolation of America during most Cenozoic. The (orders Notoungulata, Litopterna and Astrapotheria) Santa Cruz Formation (late Early Miocene) are particularly interesting for paleobiological studies due to their diversity, richness quality preservation specimens. body mass estimation species is one basic biological attributes reconstructions. common way estimate from fossils using linear regression. Here, we used geometric morphometric techniques in order mass. We regressions based on centroid size 3D craniomandibular landmark configurations, including extant (their ecological relatives). Cases were weighted maximize taxonomic evenness. A broad range was recorded. highest predictive power obtained with those functions derived diversity. corresponds masses below 100 kg. Among typotheres (Hegetotheriidae + Interatheriidae) vary 1 less than 10 kg, while smaller toxodontid reached 100 kg larger 500 kg. Litoptern proterotheriid 10 50 kg, macraucheniids surpass astrapotheres (Astrapotheria) (or even surpassed) 1000 kg, being only megamammal Santacrucian ungulate assemblage.