分子进化速率

许多研究证明，分子进化速率不是恒定的。

Many studies indicated that the rate of evolution is not stable .

基于生物的遗传距离所建立的分子进化速率，可用于进一步推测不同生物类群在进化历史上的分歧时间。

Based on genetic distances , molecular evolution rates established by the hypothesis of molecular clock can be used to deduce the origin or divergence time of different organism taxa .

众所周知，物种分化年代的估计对分子钟（进化速率恒定）假定很敏感。

Estimation of species divergence times is well known to be sensitive to violation of the molecular clock assumption ( rate constancy over time ) .

线粒体DNA是核外遗传物质，由于其分子结构简单、进化速率快等特点常被用来进行遗传多样性分析和系统发育研究。

( mtDNA ) is extra-nuclear genetic material , it is usually used in genetic diversity analysis and phylogeny study because of its brief molecule structure and rapid evolutionary rate .