首页 | 本学科首页   官方微博 | 高级检索  
   检索      


Sexual isolation between two sibling species with overlapping ranges: Drosophila santomea and Drosophila yakuba
Authors:Coyne Jerry A  Kim Soo Y  Chang Audrey S  Lachaise Daniel  Elwyn Susannah
Institution:Department of Ecology and Evolution, The University of Chicago, 1101 East 57th Street, Chicago, Illinois 60637;Department of Ecology and Evolution, The University of Chicago, 1101 East 57th Street, Chicago, Illinois 60637 E-mail:;Department of Ecology and Evolution, The University of Chicago, 1101 East 57th Street, Chicago, Illinois 60637 E-mail:;Laboratoire Populations, Génétique et Evolution, CNRS, 91198 Gif-sur-Yvette, France;Laboratoire Populations, Génétique et Evolution, CNRS, 91198 Gif-sur-Yvette, France E-mail:;Laboratoire Populations, Génétique et Evolution, CNRS, 91198 Gif-sur-Yvette, France E-mail:
Abstract:Abstract.— .Drosophila yakuba is widespread in Africa, whereas D. santomea, its newly discovered sister species, is endemic to the volcanic island of São Tomé in the Gulf of Guinea. Drosophila santomea probably formed after colonization of the island by a D. yakuba‐like ancestor. The species presently have overlapping ranges on the mountain Pico do São Tome, with some hybridization occurring in this region. Sexual isolation between the species is uniformly high regardless of the source of the populations, and, as in many pairs of Drosophila species, is asymmetrical, so that hybridizations occur much more readily in one direction than the other. Despite the fact that these species meet many of the conditions required for the evolution of reinforcement (the elevation of sexual isolation by natural selection to avoid maladaptive interspecific hybridization), there is no evidence that sexual isolation between the species is highest in the zone of overlap. Sexual isolation is due to evolutionary changes in both female preference for heterospecific males and in the vigor with which males court heterospecific females. Heterospecific matings are also slower to take place than are homospecific matings, constituting another possible form of reproductive isolation. Genetic studies show that, when tested with females of either species, male hybrids having a D. santomea X chromosome mate much less frequently with females of either species than do males having a D. yakuba X chromosome, suggesting that the interaction between the D. santomea X chromosome and the D. yakuba genome causes behavioral sterility. Hybrid F1 females mate readily with males of either species, so that sexual isolation in this sex is completely recessive, a phenomenon seen in other Drosophila species. There has also been significant evolutionary change in the duration of copulation between these species; this difference involves genetic changes in both sexes, with at least two genes responsible in males and at least one in females.
Keywords:Mate discrimination  reinforcement  reproductive isolation  sexual isolation  speciation
本文献已被 PubMed 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号