Speciation in nature: the threespine stickleback model systems

• Published in: Trends in Ecology & Evolution Vol. 17; no. 10; pp. 480 - 488
• Main Authors: McKinnon, Jeffrey S., Rundle, Howard D.
• Format: Book Review Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.10.2002; Elsevier
• Subjects: Agnatha. Pisces; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Autoecology; Biological and medical sciences; Biological evolution; divergent selection; ecological speciation; founder effect; Fundamental and applied biological sciences. Psychology; Gasterosteus; Gasterosteus aculeatus; Genetics of eukaryotes. Biological and molecular evolution; reproductive isolation; stickleback; Vertebrata; divergent selection; ecological speciation; Gasterosteus; founder effect; Genetics; Evolution; reproductive isolation; Ecology; stickleback; Vertebrata; Reproductive isolation; Sexual selection; Pisces; Models; Gasterosteus aculeatus; Speciation; Natural selection
• ISSN: 0169-5347; 1872-8383
• DOI: 10.1016/S0169-5347(02)02579-X

The threespine stickleback Gasterosteus aculeatus species complex is an important natural model for speciation research because it includes several replicated sets of coexisting, divergent forms that are also experimentally tractable. Recent research has begun to emphasize lesser known divergences within the complex in addition to the well-studied limnetic–benthic pairs, as well as exploring a broader range of speciation mechanisms. With the goals of making general inferences about speciation in nature and bringing this body of research to a wider audience, we have surveyed studies from the entire species complex. We find that stickleback speciation is often rapid, that the geographical context of speciation is variable and often complex, and that many, diverse traits have often diverged early in the speciation process. We find no unambiguous evidence of founder-effect speciation, but much evidence that divergent natural and sexual selection have been central to the evolution of reproductive isolation in this species complex. To better understand how speciation commonly occurs in nature, we review studies of the threespine stickleback, focusing on the geography, rate, and mechanisms of stickleback speciation