Normal Variations in Fossils and Recent Human Groups

Abstract

What is normality in terms of variation seen in fossil remains or the large skeletal samples excavated from sites of the last 10,000 years? There tends to be an assumption that we know what the boundaries of normality are, and thus “abnormality” presents no problems in terms of its differentiation. But this seems to be a matter for some debate, and intrapopulation studies on biological variation in skeletal and dental remains are by no means common. In particular, variation revealed by radiographic study is so far poorly reported in the literature. Moreover, it is probably true to say that variation in fossil humans has been especially neglected, and this applies to revealing and confirming pathology as well as establishing normal variation. A few examples will establish the ways in which x-rays could have assisted in extending our paleontological knowledge. Take for instance the East African skulls KNM-ER 406, KNM-ER 1470, and KNM-ER 1813 (Leakey et al. 1978), x-rays and computed tomography (CT) scans would have provided important extra information about cranial thickness, size and shape of frontal, maxillary, and mastoid sinuses, and perhaps even information on the basicranial angle and size and shape of the sella turcica. In the same way, xrays were needed to fully appreciate the morphology and degree of breakage and distortion of the Arago XXI skull (de Lumley 1981).