A probabilistic approach to the problem of sexual dimorphism in Homo habilis: a comparison of KNM-ER 1470 and KNM-ER 1813

Abstract

Craniofacial traits of two crania from Koobi Fora, Kenya, KNM-ER 1470 and KNM-ER 1813, are compared to determine the probability that they are from the same species, Homo habilis. It is argued that unless Homo habilis was significantly more sexually dimorphic than Gorilla gorilla, it is improbable that the two fossils can both be classified as Homo habilis. The creation of at least one new species is required to account for the morphological and metrical variation of Late Pliocene-Early Pleistocene Homo fossils in eastern Africa.