Thinking outside the box: a lemur's take on hominin craniodental evolution.

Abstract

Cerling et al. (1) and Lee-Thorp (2) presented formidable evidence against nut consumption by the so-called “Nutcracker Man,” robust australopith Paranthropus boisei. Unusually high δ13C isotope values bear testimony, instead, to a diet rich in C4 resources (e.g., grasses, sedges). Such isotope values are rivaled, among anthropoid primates, only by those of the extinct gelada baboon, Theropithecus oswaldi. There is, however, another primate with similar carbon isotope values, a fossil lemur from Madagascar, Hadropithecus stenognathus (Fig. 1). When, in 1970, Jolly advanced his gelada analog for P. boisei, he erected a similar model for Hadropithecus (3). Indeed, the craniodental convergences of H. stenognathus to P. boisei (4, 5) are stronger than those of gelada baboons.