Implications of KNM-WT 17000 for the Evolution of “Robust” Australopithecus

In previous contributions we have stressed the need for new East African hominid fossils in the 2.0-3.0 Myr time range to test competing phylogenetic hypotheses (Johanson and White, 1979; White et al., 1981; Kimbelet al., 1984, 1986). The recent recovery of an Australopithecus cranium from 2.5 ± 0.07 Myr sediments at Lomekwi, west of Lake Turkana, Kenya, provides a basis for this test (Walker et al., 1986). The cranium, KNM-WT 17000, already has stimulated considerable discussion (Bower, 1986, 1987; Delson, 1986; Falk, 1986; Johanson and White, 1986; Lewin, 1986; Shipman, 1986). The occasion of a workshop devoted to the evolution of “robust�? 1 early hominids affords an appropriate opportunity to assess the taxonomic and phylogenetic implications of KNM-WT 17000.