化石人类脑演化研究概况

脑演化是人类演化的一个重要组成部分，其研究可以为人类起源、演化、人群关系及语言、智力等方面提供重要的信息。脑演化的主要证据是通过研究颅内模（endocast）及颅骨的形态得到的。颅内模是从颅骨内表面得到的脑的外部形态。有时颅骨的内腔充满泥沙，并且为钙质所结固，可以自然形成颅内模。也可以人工制作颅内模。颅内模和颅骨的内表面能够提供人类脑髓及神经进化方面的直接证据。对化石人类脑演化的研究主要包括以下几个方面的内容：测量或估计脑量的大小及其和身体大小之间的关系；研究脑量随时间的变化过程；通过对早期人类颅内模表面沟回形态特征的研究，探索脑功能区在早期人类和猿类的区别及在演化上的变化；左右大脑不对称性与一侧优势关系，探讨语言的起源和惯用手的脑功能基础等；脑膜中动脉系统、静脉窦系统及与血液循环相关的排泄孔的变化，探讨大脑各部分比例的变化和功能的日益复杂对供血需求的影响；通过对人类脑演化的研究，探讨人类进化的原因。本文通过对以上几个方面及其中国化石脑演化研究的介绍，对化石人类脑演化的研究概况作综合论述和简单回顾。

THE STUDY OF FOSSIL HOMINID BRAINS

The direct evidence of the fossil hominid brains evolution comes from the study of skulls and endocranial casts (endocasts). Endocasts of fossil hominids have been a focus of attention and controversy in paleoanthropology for as long as there has been a record of fossil hominids.There have several foci of this attention.The first concerns the evolution of cranial capacity and their relationship to body size. A second area of fossil hominid brains involves the sulcal patterns on endoasts. A third focus of attention concerns right-left asymmetries in the fossil hominid brains. A forth focus concerns the pattern of blood flow to and from the brain.Endocast preserves numernous details of both the meningeal and venous sinus system. Finally, much of the literature has been devoted to speculation the factors that account for the expension of the primitive hominid brain. With the review of fossil hominid brains, the main aim is to get some information in light of the study of the Chinese fossil hominids.