Multi regional continuity the fossil evidence
Multi-regional continuity: the fossil evidenceMulti-Regional Continuity: The Fossil Evidence
With regards to the multi-regional continuity model of human evolution, there is without a doubt a preponderance of fossil data that supports the diverse origins of Homo sapiens in different regions of the globe. Skulls displaying a wide variety of mixed modern and archaic features have been found in every corner of the world. The mere existence of these fossils is evidence enough to prove that human evolution was far less cut-and-dried a process than the advocates of the replacement model of human evolution would like to suggest, and, in fact, rather astonishingly complex.
It is useful before discussing the individual fossil specimens to to preface with what exactly is meant by the terms “modern” and “archaic” in reference to skull morphology. “Modern” features in skull morphology as the word is used here include thin cranial walls, small supraorbital ridges, small teeth, small eye sockets, broad, flat foreheads, large cranial volume (above 1200 cc.), low prognathism in the area of the lower face, and a high, vaulted shape in the area of the cranium. “Archaic” features in skull morphology include thick cranial walls, heavy supraorbital ridges, large teeth, large eye sockets, sloping foreheads, low cranial volume (below 1200 cc.), high prognathism in the area of the lower face, and a small, football-shaped cranium. The presence of various mixtures of these modern and archaic traits forms the basis for identifying a fossil as transitional modern/archaic in accordance with the multi-regional continuity model of human evolution.
As an example of transitional fossils found outside of Africa and in accordance with the multi-regional model of human evolution, the remains found in the Ngangdong beds of the Solo River in Indonesia are an excellent beginning. Dating from roughly 250,000 years ago, the skulls of the thirteen individual recovered lack faces, but the crania are markedly archaic, football-shaped and flattened in general contour (Poirier 1987: 222). Other archaic features include heavy supraorbital ridges and thick cranial walls (222). Their archaic features put the Solo remains in the classification of Homo erectus, but the skulls display at least one distinctive modern trait: they have, as a group, a much larger cranial volume than average Homo erectus specimens, as high as 1,300 cc. (222). The occurence of this modern cranial capacity with other archaic traits in specimens consistent with a limited geographical setting suggests a local transition from primitive to more modern traits, as would be expected from the multi-regional continuity model of human evolution.
Crossing over the distance of two continents, the next fossil was recovered from a gravel pit in Swanscombe, England, and is believed to date from 250,000 years ago. The Swanscombe skull consists of an occipital bone and left and right parietals, all well-preserved (1987: 223-224). The cranial volume has been estimated at 1,275 to 1,325 cc., putting it well within the range of modern populations. There are...
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