Carnivoran paleoguilds of Africa: implications for hominid food procurement strategies.

Tool-using hominids, as carnivorous animals, would have been part of the various carnivore guilds present in Plio-Pleistocene Africa. Hominid dietary strategies must be understood within the larger context of carnivore behavior and ecology, as carnivorans could have affected the abilities of hominids to procure meat and/or marrow. The functional anatomy of extant and fossil carnivorans was examined to infer behaviors in fossil carnivorans that would have impacted on hominid dietary strategies in terms of carcass availability. Comparisons of guild structure were carried out to examine changes in carnivoran interactions and their implications for hominid behavior. Plio-Pleistocene carnivorans engaged in a wider range of behaviors than modern carnivorans. The sabertoothed felids Dinofelis and Megantereon probably did not provide much larger carcasses than modern species. Another sabertooth, Homotherium generated larger carcasses, but may have disarticulated and transported these carcasses. Fossil representatives of modern taxa may not have been equivalent ecologically within the carnivoran guild. Overall, hominids in eastern Africa probably had a greater range of scavenging opportunities than did those of southern Africa during the Plio-Pleistocene. Local and continent-wide extinction events in large-bodied carnivoran guilds from 1 to 2 Ma had a substantial effect on carcass availability and the risk to hominid scavengers. These structural changes in the carnivore guild may have provided an opportunity for hominids to widen their niche with respect to dietary behavior.