Devaux Céline, Lande R
Division of Biological Sciences, University of California - San Diego, La Jolla, CA, USA.
J Evol Biol. 2009 Jul;22(7):1460-70. doi: 10.1111/j.1420-9101.2009.01762.x. Epub 2009 May 7.
We model the evolution of allochronic isolation between sympatric animal-pollinated plant species via displacement of their flowering times. The plant species share generalist pollinators and either produce inviable hybrid seeds or do not hybridize at all. Displacement of flowering times between reproductively isolated species reduces competition for pollinators and the formation of inviable hybrid seeds. Under strong pollen limitation, competition for pollinators causes rapid evolution of allochronic isolation both for hybridizing and nonhybridizing species. Under weak pollen limitation, allochronic isolation evolves rapidly for hybridizing species but more slowly for nonhybridizing species. Positive density-dependent pollinator visitation rate at low flower densities facilitates allochronic isolation under weak pollen limitation. Allochronic isolation among sympatric species sharing generalist pollinators could be common under any intensity of pollen limitation if the flowering season is sufficiently long.
我们通过花期的偏移来模拟同域动物传粉植物物种之间异时隔离的演化。这些植物物种共享广食性传粉者，要么产生不育的杂交种子，要么根本不杂交。生殖隔离物种之间花期的偏移减少了对传粉者的竞争以及不育杂交种子的形成。在强花粉限制下，对传粉者的竞争导致杂交和非杂交物种的异时隔离迅速演化。在弱花粉限制下，杂交物种的异时隔离迅速演化，而非杂交物种的演化则较为缓慢。在低花密度下正密度依赖的传粉者访花率在弱花粉限制下促进了异时隔离。如果花期足够长，在任何花粉限制强度下，共享广食性传粉者的同域物种之间的异时隔离都可能很常见。
