Department of Plant Biology, University of Minnesota, St. Paul, MN, 55108, USA.
Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, MN, 55108, USA.
Ecol Lett. 2015 Jul;18(7):706-13. doi: 10.1111/ele.12449. Epub 2015 May 18.
Species' geographic ranges vary enormously, and even closest relatives may differ in range size by several orders of magnitude. With data from hundreds of species spanning 20 genera in 15 families, we show that plant species that autonomously reproduce via self-pollination consistently have larger geographic ranges than their close relatives that generally require two parents for reproduction. Further analyses strongly implicate autonomous self-fertilisation in causing this relationship, as it is not driven by traits such as polyploidy or annual life history whose evolution is sometimes correlated with selfing. Furthermore, we find that selfers occur at higher maximum latitudes and that disparity in range size between selfers and outcrossers increases with time since their evolutionary divergence. Together, these results show that autonomous reproduction--a critical biological trait that eliminates mate limitation and thus potentially increases the probability of establishment--increases range size.
物种的地理分布范围差异巨大，即使是最亲近的亲属，其分布范围大小也可能相差几个数量级。我们利用来自 15 个科的 20 个属的数百个物种的数据表明，通过自花授粉自主繁殖的植物物种的地理分布范围普遍大于其近亲，后者通常需要两个亲本才能繁殖。进一步的分析强烈表明，自主自交导致了这种关系，因为它不是由多倍体或一年生生活史等特征驱动的，这些特征的进化有时与自交有关。此外，我们发现自交种出现在更高的最大纬度，并且自交种和异交种之间的分布范围大小差异随着它们进化分歧的时间而增加。总之，这些结果表明，自主繁殖——一种消除配偶限制的关键生物学特征，从而可能增加建立的可能性——会增加分布范围。
