Dissertation Research: Dental Variation in Hominoids: Its Implications for Fossil Species Recognition

这个项目将研究四组现存的类人猿的牙齿变异：大猩猩、黑猩猩、猩猩和长臂猿。新的图像分析技术将用于精确测量这些类人猿牙齿表面的形态特征。将研究来自各个博物馆的大量标本，以便对所有地理种群进行采样。本研究的重要意义在于：(1)对化石物种的鉴别具有重要意义。牙齿特征一直被用来区分化石物种，但由于样本量有限，物种区分特征的变化性质和模式无法研究。本研究将提供一个详尽的类人猿变异模式的比较数据库，以比较类人猿化石物种中相似特征的变异。它将有助于理解人类在自然界中的地位。对牙齿变异程度和模式的研究将有助于理解类人猿群内和群间的关系。这是一组与人类关系最密切的灵长类动物，它将有助于理解人类的系统和进化关系。(3)有助于了解古人类的保护状况。一些类人猿的物种和亚种在它们的自然栖息地面临灭绝的威胁，国际社会为拯救它们付出了很多努力。本文提出的牙齿变异研究将有助于理解不同类人猿种群、亚种和种之间的分类和相互关系。这对于形成关于类人猿保护需要的明智意见至关重要。

This project will study dental variation in four groups of living hominoids: gorillas, chimpanzees, orang-utans, and gibbons. Novel image-analysis techniques will be used to accurately measure morphological features on the dental surface of these apes. A large number of specimens from various museums will be studied, so as to sample all geographical populations. This study is important for several reasons: (1) It will have implications for fossil species discrimination. Dental characters are consistently used to differentiate fossil species, but because of limited sample sizes, the nature and patterns of variation in species differentiating characters cannot be studied. The present study will provide an exhaustive comparative database of patterns of variation in living hominoids against which variation in similar characters in fossil hominoid species can be compared. (2) It will help in understanding the place of humans in nature. A study of the degree and pattern of dental variation will help in understanding the within- and between-grouprelationships of the hominoids. This being the group of primates most closely related to humans, it will help in understanding of the systematic and evolutionary relationships of humans. (3) It will help in understanding the conservation status of the hominoids. Several species and subspecies of hominoids are threatened with extinction in their natural habitat, and much international effort is expended in trying to save them. The study of dental variation as proposed here will help in understanding the taxonomy and interrelationships of the various populations, subspecies and species of hominoids. This is critical for forming informed opinions on the need for conservation in the hominoids.