Feeding ecology of the gomphotheres (Proboscidea, Gomphotheriidae) in North and South America

PRADO, J. L.; PEREZ-CRESPO, A.; ARROYO-CABRALES, J.; ALBERDI, M. T.

Taichung, Taiwan

Conferencia; VII International Conference of Mammoths and Their Relatives; 2017

Gomphotheriidae was a family within the Order Proboscidea that migrated during the late Eocene from Africa into Asia, Europe, and North America, and during the Great American Biotic Interchange, they move into South America. During this process, the family diversified into a large number of genera and species, with a wide range of feeding patterns. In the Americas, the genera Gomphotherium and Amebelodon from the Early Miocene, were animals that ate C3 plants, while the Late Miocene Gomphotherium mainly had C4 plants in its diet. During the Pliocene, the genus Rynchotherium was a generalist animal, with some individuals either specializing as C3 or C4 plant eaters, or having a C3/C4 mixed diet. During the Pleistocene, the genera Cuvieronius and Stegomastodon, which distributed in both North and South America, had a largely varied diet, with North American Cuvieronius with the largest variation having both the C3 or C4 plant specialists or the C3/C4 mixed diets, while South American Cuvieronius was mostly C3-plant eaters or C3/C4 mixed eaters. . The other genus, Stegomastodon had individuals exclusively eating C3 or C4 plants, as well as animals having a C3/C4 mixed diet; for North America, this genus was mostly a C3/C4 mixed eater. All of the above points out that gomphotheres were capable to adapt to climate change, like the origin of C4 plants during the Late Miocene, maintaining plasticity in their feeding habits, which could be the cause of their survival into the Late Pleistocene in the America. In general, the gomphothere specimens from South American middle Pleistocene exhibit feeding strategies similar to those of modern elephants: they lived in diverse habitats, were opportunists, and therefore were capable of living on nearly any dietary mixture, In contrast, late Pleistocene populations showed more selective dietary adaptations, which suggests that gomphoteres were driven to extinction because they were specialized feeders, adapted to a kind of plants that disappeared during the Holocene.