The findings could potentially put to rest the decades-long debate between proponents of the regional continuity model of human origins, which maintains that Neanderthals are a subspecies of Homo sapiens which contributed significantly to the evolution of modern Europeans, and the single-origin model, which views Neanderthals as a separate, distinct species. The research will be published in the Proceedings of the National Academy of Sciences.
The scientists, led by Katerina Harvati of New York University, used a new technique known as geometric morphometrics to measure the degree of variation between and amongst living primate species, represented by over 1000 specimens. The scientists measured 15 standard craniofacial landmarks on each of the skulls and used 3-D analysis to superimpose each one in order to measure their shape differences, irrespective of size. Random samples were chosen from each species and the differences between them were calculated 10,000 times, in order to simulate the sampling effects of the fossil record. . The data used included Neanderthal fossils , Upper Paleolithic European modern human fossils, and recent human populations, as well as data from living African apes and Old World Monkeys.
"Our motivation was to devise a quantitative method to determine what degree of difference justified classifying specimens as different species," said Harvati. "The only way we could effectively do this was to examine the skeletal morphology of living species today and come up with models. From these data, we were able to determine how muc
Contact: Shonna Keogan
New York University