生物进化过程中人类脑容量的演变

Abstract

在生物进化的过程中，动物的神经系统从低级到高级，不断地由简单到复杂进行过渡，到脊椎动物最终形成了高级、复杂的大脑。而脑容量的演变是随着动物神经系统的进化而逐渐发展的，动物从低等到高等，脑容量逐渐增大。人类脑容量的演变趋势总体呈现为“两头缓慢，中间迅速”的“S”型曲线式发展；从“能人”时期开始，人类的脑容量迅速扩张；而经“智人”后，人类脑容量的发展渐趋平缓；脑容量的扩增在一定程度上可能促进了人类智力和认知能力的提升。脑容量的变化受到了包括基因和行为等多种因素的共同调节；就人类而言，诸如工具的制造和使用，劳动的日益增加，语言文字的形成，食性由素食向肉食转变等等，这些都对脑容量的进化起到了至关重要的推动作用。 In the process of biological evolution, the animal’s nervous system has experienced a process from simple to complex, the advanced, sophisticated brain eventually formed until to the appearance of the vertebrate. And with the evolution of the animal’s nervous system, the brain volume increases gradually. As to the human beings, the overall development trend of brain volume evolution ap-pears as a “S” curve type; from the “Homo habilis” period, the brain volume starts expansion rapidly; and after the period of “Homo sapiens”, the development of human brain volume becomes stable; the distensible brain volume may cause the improvement of human’s intelligence and cognitive abilities. Brain volume is regulated by many factors, including gene and behavior; In humans, the things such as the manufacture and the use of tools, the increasing of labor, the formation of language, changing of feeding from vegetarian to carnivorous all play a crucial role in promoting the brain volume evolution.