Dissertation Research: A Quantitative Assessment of Frontal Bone Morphological Variation in Middle Pleistocene Homo Using Fourier Analysis

我们属在中更新世的演化是一个争议点。一些人认为地理上分散的、形态上不同的种群是单一物种的成员。其他人则将种群间的形态差异解释为物种水平的显著差异。额骨是在试图在这两种模式之间做出决定时提供重要数据的元素，因为它提供了关于头骨两个区域的变化的数据：脑颅和内脏头盖骨。此外，额部的特征被用来区分直立人和智人。这项研究将利用形态计量学方法--椭圆傅里叶函数分析--对中更新世“古老的”人类标本(包括尼安德特人)的额骨形态进行量化。将收集和量化额骨的冠状面、正中矢状面和矢状面旁的边界轮廓数据。为了建立与早更新世和晚更新世相邻的额骨的时间趋势，将对额骨进行量化。与化石一致的9个种群中的20个现代人的地理变异也将被确定。对这些假设的分析将阐明额骨的特征是如何作为性格复合体相互关联的，以及这些性格如何反映潜在的变异来源，如性别和大小。这项研究将有助于对中更新世人类进化做出更有见地的推断。

The evolution of our genus during the Middle Pleistocene is a point of contention. Some view geographically dispersed, morphologically differentiated populations as members of a single species. Others interpret morphological variation among groups as signifying species level differences. The frontal bone is an element that can provide significant data in attempting to decide between these two models as it provides data regarding alterations in two regions of the skull: the neurocranium and the splanchnocranium. Additionally, traits of the frontal are used to distinguish Homo erectus and Homo sapiens. This research will utilize a morphometric procedure, Elliptical Fourier Function Analysis to quantify the morphology of the frontal bone in a sample of 'archaic" Homo specimens (including Neanderthals) dated to the Middle Pleistocene. Boundary outline data of coronal, mid-sagittal and parasagittal slices of the frontal bone will be collected and quantified. To establish temporal trends neighboring Early and Late Pleistocene frontal bones will be quantified. Geographic variation will also be ascertained in twenty modern humans from each of nine populations coincident with the fossils. Analysis of the hypotheses will clarify how features of the frontal bone are interrelated as character complexes and how these characters reflect potential sources of variation such as gender and size. This research will contribute to more informed inferences about hominid evolution in the Middle Pleistocene.