Evolution of polymorphism
Female brown anoles occur in three distinct dorsal-pattern morphs (L-R): Bar, Diamond-Bar, and Diamond.
How does natural selection create and maintain discrete phenotypic variation?
Evolution by natural selection cannot occur without phenotypic and genetic variation, yet selection depletes this very stock of variation. How does variation persist despite chronic selection? Polymorphism offers insight into this question because phenotypic variation can be partitioned into discrete “morphs”, often corresponding to simple genetic differences at one or several loci. On the Great Bahamas Bank, female brown anoles exhibit one of three distinct dorsal patterns: Diamond (D), Bar (B), and intermediate Diamond-Bar (DB) morphs. Ryan Calsbeek, Lauren Bonvini and I have begun to study this sex-limited polymorphism to elucidate its genetic basis and determine whether it is maintained by natural selection.
Last updated 23 July, 2009
Related Papers
Calsbeek, R., L. Bonvini, and R.M. Cox. In press. Geographic variation, frequency-dependent selection, and the maintenance of a female-limited polymorphism. Evolution.
Check out Ryan Calsbeek’s lab for other papers related to the evolution of polymorphism in anoles.