Feeding ecology of the gomphotheres (Proboscidea, Gomphotheriidae) of America

Based on data from analyses on previously-reported carbon stable isotope data from dental enamel and dentine from tusks reported in the literature, diets were inferred for the gomphothere genera Amebelodon, Cuvieronius, Gomphotherium, Rhynchotherium, Serbelodon, and Stegomastodon (Proboscidea, Gomphotheriidae) that inhabited the Americas during the Cenozoic. Amebelodon, Gomphotherium, and Serbelodon specimens of the Barstovian and Clarendonian faunal stages fed on C3 plants; while the same Hemphillian genera consumed a mixed C3/C4 diet. Hemphillian Rhynchotherium were mixed-diet feeders while Blancan specimens of the same genus fed on C3 plants. Stegomastodon from the same Blancan period consumed a mixed C3/C4 diet, similar to Rancholabrean animals, although Lujanian specimens ate C3 plants. As for the genus Cuvieronius, Irvingtonian, Rancholabrean, and Lujanian specimens consumed a mixed C3/C4 diet. These results suggested that American gomphotheres displayed generalist feeding habits, allowing them to inhabit different environments in extensive areas of the continents, and survive to the end of the Pleistocene. •δ13C values of Cenozoic American gomphotheres are presented.•The early Miocene North American gomphotheres were specialists in C3 plant consumption.•Late Miocene to Pleistocene North American gomphotheres and Pleistocene South American gomphotheres were generalists in their diet.•This plasticity in gomphothere diet allowed them to live across the Americaswhile mammoth and American mastodon only reached to Costa Rica.