A novel method has been developed that may prove to be a valuable tool in clarifying the picture. In the March 30, 2004 issue of the Proceedings of the National Academy of Sciences, a form of three-dimensional mathematical analysis is used to quantify bone characteristics of humans and eight species and subspecies of great apes and to arrive at a clear family tree that defines ancestral relationships down to the subspecies level. The analysis relies solely on bone shape but its results agree with genetic analyses.
In the paper, authors Charles A. Lockwood of the Department of Anthropology at University College London (formerly of Arizona State University), William H. Kimbel of the Institute of Human Origins and Department of Anthropology at ASU, and John M. Lynch of ASU's Barrett Honors College apply a methodology, known as geometric morphometric analysis, to shape data from the temporal bones of humans and eight other species, including chimpanzees, gorillas and orangutans. The application of the method was developed under a National Science Foundation grant and the methodology was previously outlined in the December 2002 issue of the Journal of Anatomy.
"In this work we aimed to link modern quantitative methods, which are undergoing something of a revolution, with the analysis of a part of the skull we were interested in for a variety of reasons," said Lockwood.
Kimbel adds, "The temporal bone has long been thought to have taxonomic and phylogenetic significance and seemed like an ideal target. Because of its unique place in the skull, its shape says a lot about a species." The complex shape of the temporal bone is influenced by many
Contact: James Hathaway
Arizona State University