A central problem in evolutionary biology is to understand how spatial and temporal variation in selection maintains genetic variation within and among populations. Brown anole lizards (Anolis sagrei) exhibit a dorsal pattern polymorphism that is expressed only in females, which occur in “diamond”, “bar”, and intermediate “diamond-bar” morphs. We are currently testing the hypothesis that this polymorphism is maintained by temporal variation in selection coupled with the sheltering of alleles via a two-locus inheritance pattern and sex-limited expression. Additional work involves understanding the potential importance of gene-flow between populations with divergent morph frequencies.
Related Publications
PDF Calsbeek, R., Bonvini, L., Cox, R.M. Geographic variation, frequency dependent selection, and the maintenance of a female limited polymorphism. Evolution 64: 116-125.
PDF Calsbeek R., Bonneaud, C. and Smith T.B. Differential fitness effects of neighborhood density and immunocompetence in alternative female lizard morphs. J. Animal Ecology 77: 103-109 .
PDF Sinervo, B. and Calsbeek, R. The physiological, behavioral, and genetical causes and consequences of frequency dependent selection in the wild. Annual Review of Ecology Evolution and Systematics. 37: 581-610.
PDF Calsbeek, R. and Smith, T.B. Ocean currents mediate gene flow in island lizards Nature 426: 552-555