Centre for Macroevolution and Macroecology, Evolution, Ecology and Genetics, Research School of Biology, Australian National University, Canberra.
Philos Trans R Soc Lond B Biol Sci. 2011 Sep 12;366(1577):2503-13. doi: 10.1098/rstb.2011.0014.
DNA sequences evolve at different rates in different species. This rate variation has been most closely examined in mammals, revealing a large number of characteristics that can shape the rate of molecular evolution. Many of these traits are part of the mammalian life-history continuum: species with small body size, rapid generation turnover, high fecundity and short lifespans tend to have faster rates of molecular evolution. In addition, rate of molecular evolution in mammals might be influenced by behaviour (such as mating system), ecological factors (such as range restriction) and evolutionary history (such as diversification rate). I discuss the evidence for these patterns of rate variation, and the possible explanations of these correlations. I also consider the impact of these systematic patterns of rate variation on the reliability of the molecular date estimates that have been used to suggest a Cretaceous radiation of modern mammals, before the final extinction of the dinosaurs.
DNA 序列在不同物种中的进化速度不同。这种速率变化在哺乳动物中得到了最密切的研究，揭示了大量能够影响分子进化速度的特征。这些特征中有许多是哺乳动物生活史连续体的一部分：体型小、世代更替快、繁殖力高、寿命短的物种往往具有更快的分子进化速度。此外，哺乳动物的分子进化速度可能受到行为（如交配系统）、生态因素（如范围限制）和进化历史（如多样化率）的影响。我讨论了这些速率变化模式的证据，以及这些相关性的可能解释。我还考虑了这些系统的速率变化模式对分子日期估计可靠性的影响，这些估计曾被用来暗示现代哺乳动物在恐龙最终灭绝之前的白垩纪辐射。
