One approach to understand the importance of reproductive barriers to the speciation process is to study the break- down of barriers between formerly distinct species. One reproductive barrier, sexual isolation, reduc...One approach to understand the importance of reproductive barriers to the speciation process is to study the break- down of barriers between formerly distinct species. One reproductive barrier, sexual isolation, reduces gene flow between species through differences in mate preferences and mating signals and is likely important for species formation and maintenance. We measure sexual isolation in two limnetic-benthic threespine stickleback species pairs （Gasterosteus spp.）. One species pair main- tains strong reproductive isolation while the other species pair has recently collapsed into a hybrid swarm. We compare the strength of sexual isolation in the hybridizing pair to the currently isolated pair. We provide the first evidence that sexual isolation has been lost in the hybridizing pair and show furthermore that preferences females have for conspecific mates and the traits they use to distinguish conspecific and heterospecific males contribute to this loss. This work highlights the fragility of reproductive isolation between young species pairs and considers the role of sexual isolation in speciation [Current Zoology 59 （5）： 591-603, 2013].展开更多
基金Acknowledgements We thank C. Long and M. Rounds for help with data collection. Thanks to Tom Getty, Genevieve Kozak, Michael Jennions, several anonymous reviewers, and the Boughman lab for helping to improve this manuscript. Research was conducted under permits from the Ministry of the Environment, BC and approval from University of Wis- consin-Madison Institutional Animal Care and Use Committee. This work was supported by the Emlen Fund from the Zoolo- gy Department of the University of Wisconsin, Madison to ACRL and the National Science Foundation to JWB.
文摘One approach to understand the importance of reproductive barriers to the speciation process is to study the break- down of barriers between formerly distinct species. One reproductive barrier, sexual isolation, reduces gene flow between species through differences in mate preferences and mating signals and is likely important for species formation and maintenance. We measure sexual isolation in two limnetic-benthic threespine stickleback species pairs （Gasterosteus spp.）. One species pair main- tains strong reproductive isolation while the other species pair has recently collapsed into a hybrid swarm. We compare the strength of sexual isolation in the hybridizing pair to the currently isolated pair. We provide the first evidence that sexual isolation has been lost in the hybridizing pair and show furthermore that preferences females have for conspecific mates and the traits they use to distinguish conspecific and heterospecific males contribute to this loss. This work highlights the fragility of reproductive isolation between young species pairs and considers the role of sexual isolation in speciation [Current Zoology 59 （5）： 591-603, 2013].
