Department of Biology, University of North Carolina, , Chapel Hill, NC 27517, USA.
Philos Trans R Soc Lond B Biol Sci. 2010 Feb 27;365(1540):577-91. doi: 10.1098/rstb.2009.0244.
A major goal of evolutionary biology is to identify the causes of diversification and to ascertain why some evolutionary lineages are especially diverse. Evolutionary biologists have long speculated that polyphenism--where a single genome produces alternative phenotypes in response to different environmental stimuli--facilitates speciation, especially when these alternative phenotypes differ in resource or habitat use, i.e. resource polyphenism. Here, we present a series of replicated sister-group comparisons showing that fishes and amphibian clades in which resource polyphenism has evolved are more species rich, and have broader geographical ranges, than closely related clades lacking resource polyphenism. Resource polyphenism may promote diversification by facilitating each of the different stages of the speciation process (isolation, divergence, reproductive isolation) and/or by reducing a lineage's risk of extinction. Generally, resource polyphenism may play a key role in fostering diversity, and species in which resource polyphenism has evolved may be predisposed to diversify.
进化生物学的一个主要目标是确定多样化的原因，并确定为什么某些进化谱系特别多样化。进化生物学家长期以来一直推测，多态性——即单个基因组对不同环境刺激产生替代表型——促进了物种形成，特别是当这些替代表型在资源或栖息地利用上存在差异时，即资源多态性。在这里，我们提出了一系列重复的姊妹群比较，表明在鱼类和两栖类进化出资源多态性的类群中，物种丰富度更高，地理分布范围更广，而与缺乏资源多态性的密切相关的类群相比。资源多态性可能通过促进物种形成过程（隔离、分化、生殖隔离）的各个不同阶段，以及/或者通过降低谱系灭绝的风险，从而促进多样化。一般来说，资源多态性可能在促进多样性方面发挥关键作用，而进化出资源多态性的物种可能更容易多样化。
