JaySo83 [creativecommons license] via Wikimedia Commons
The formation of new species is typically driven by environmental adaptation. But a recent investigation of neighboring populations of threespine stickleback fish (Gasterosteus aculeatus) has now shown, for the first time, that creation of a new sex chromosome can contribute to speciation.
Lab Anim. (NY) 38, 341 (2009).
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