论文部分内容阅读
地球上曾存在过的40亿动植物种,绝大多数都绝灭了.绝灭往往是呈群集绝灭形式.关于生物群集绝灭的原因,可归纳为两大类:一类是强调生物所处环境的剧烈变化(球外事件和球内事件),另一类侧重于生物自身的演变更替.本文着重评述8种当前最流行的假说及其争议,如自然种群竞争、火山爆发、古地磁极性反转、板块运动、小行星或彗星撞击等假说作者认为,群集绝灭的原因十分复杂.往往是多种因素联合作用的结果,不能仅强调一种因素.对群集绝灭应运用综合研究方法.既要研究生物自身的兴衰更替,又要研究其所处环境的变化(球内和球外的),这样才能弄清绝灭的根本原因.
The vast majority of the 4 billion species of flora and fauna that once existed on earth are extinct, and extinction is often extinct in the form of a cluster. The reasons for the extinction of biomes can be summarized into two broad categories: The other is about the evolution of the creatures themselves.This article reviews 8 of the most popular hypotheses and their controversies such as natural population competition, volcanic eruptions, ancient The hypothesis of reversal of geomagnetic polarity, plate movement, asteroid or comet impact suggests that the reason for the extinction of the cluster is very complicated, often as a result of the combined effect of many factors and can not be emphasized only by one factor. Comprehensive research methods, both to study the biological changes of their own rise and fall, but also to study the changes in their environment (inside and outside the ball), so as to find out the root cause of extinction.