Diet and Habitat for Six American Pleistocene Proboscidean Species Using Carbon and Oxygen Stable Isotopes

Diet and habitat were estimated, based on stable isotopes, for six species of proboscideans inhabiting the Americas during the Pleistocene. In North America, Mammuthus columbi (Elephantidae) was a mixed C3/C4 herbivore inhabiting open areas, while Mammut americanum (Mammutidae) fed exclusively on C3 plants and preferred closed areas. In contrast, members of the family Gomphotheriidae showed a wide range of food preference and habitats. This is the case of Cuvieronius tropicus, a mixed-diet herbivore living in open areas. In South America, another gomphothere — Cuvieronius hyodon — inhabited open areas and had a C3-plant diet similar to others from some Southern plains such as Stegomastodon platensis. On the other hand, S. waringi from tropical South America lived in open areas and had a C3/C4 mixed diet. The fact that gomphotheres had more flexible diet habits could explain why those animals were able to cross the Panamanian Isthmus, while mammoths and mastodons did not.