Dissertation Research: Pattern of Sexual Dimorphism in Limb Joint Surfaces of Catarrhine Primates

灵长类化石样本分析中最基本的问题之一是确定它们包含多少物种。含有不同大小、形状相似(但不完全相同)的个体的样本经常在古人类学家之间引发争论，即样本是由两个相关物种(一个大，一个小)组成，还是由单一物种的两个性别(大雄性，小雌性)组成。从理论上讲，当两性在大小上有显著差异时(如狒狒和大猩猩)，他们的四肢关节也可能在形状上略有不同。这是因为，体型较大的男性会遇到比女性更大的关节应力水平，从而导致关节表面积的差异。利用视频成像和计算机分析的最新进展，这项研究将检查一些最近的东半球灵长类动物，包括猴子和猿类，肢体关节表面与性别有关的形状差异。这项研究将准确揭示男性和女性骨骼的差异，并确定性别相关形状差异的模式是否在不同物种之间相似，或者取决于动物如何走动等因素。这种对现代灵长类内性别差异的研究将为评估当前的化石组合提供关键的背景。

One of the most fundamental issues in the analysis of primate fossil samples is the determination of how many species they contain. Samples that contain differently-sized individuals of similar (but not identical) shape often incite debate among paleoanthropologists as to whether the sample is made up of two related species (one large, one small), or two sexes of a single species (large males, small females.) Theoretically, when two sexes differ significantly in size (as in baboons and gorillas), their limb joints may also differ slightly in shape. This is due to the fact that larger males will encounter relatively greater joint stress levels than females, thereby inducing differences in the surface area of the joints. Using video imaging and recent advances in computer analysis, this study will examine sex-related shape differences in the limb joint surfaces of a number of recent Old World primates, including monkeys and apes. This research will reveal exactly how the bones of males and females differ, as well as determine whether or not patterns of sex-related shape differences are similar across species, or depend upon factors such as how the animals move around. This examination of sex-based differences within modern primate taxa will provide a crucial background with which to evaluate current fossil assemblages.