TAXONOMIC AFFINITY OF THE EARLY HOMO-CRANIUM FROM SWARTKRANS, SOUTH-AFRICA

A quantitative analysis that employs randomization methods and distanc e statistics has been undertaken in an attempt to clarify the taxonomi c affinities of the partial Home cranium (SK 847) from Member 1 of the Swartkrans Formation. Although SK 847 has been argued to represent ea rly H. erectus, exact randomization tests reveal that the magnitude of differences between it and two crania that have been attributed to th at taxon (KNM-ER 3733 and KNM-WT 15000) is highly unlikely to be encou ntered in a modern human sample drawn from eastern and southern Africa . Some of the variables that differentiate SK 847 from the two early H . erectus crania (e.g., nasal breadth, frontal breadth, mastoid proces s size) have been considered to be relevant characters in the definiti on of that taxon. Just as the significant differences between SK 847 a nd the two early H. erectus crania make attribution of the Swartkrans specimen to that taxon unlikely, the linkage of SK 847 to KNM-ER 1813, and especially Stw 53, suggests that the Swartkrans cranium may have its closest affinity with H. habilis sensu late. Differences from KNM- ER 1813, however, hint that the South African fossils may represent a species of early Home that has not been sampled in the Plio-Pleistocen e of eastern Africa. The similarity of SK 847 and Stw 53 may support f aunal evidence which suggests that Sterkfontein Member 5 and Swartkran s Member 1 are of similar geochronological age. (C) 1993 Wiley-Liss, I nc.