2005/12/15 by Erica Bree Rosenblum · 3 citations
Biochemistry, Genetics and Molecular Biology · Environmental Science · #Genetic diversity and population structure #Environmental DNA in Biodiversity Studies #Evolution and Genetic Dynamics #Ecotone #Biology #Gene flow #Convergent evolution #Ecology #Adaptation (eye) #Lizard #Local adaptation #Natural selection #Evolutionary biology #Selection (genetic algorithm) #Cline (biology) #Genetic variation #Habitat #Gene #Population #Genetics #Phylogenetics
paper · doi:10.1086/498397
openalex publication_date 2005/12/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/14
Ecological transition zones, where organismal phenotypes result from a delicate balance between selection and migration, highlight the interplay of local adaptation and gene flow. Here, I study the response of an entire species assemblage to natural selection across a common ecotone. Three lizard species, distributed along a dramatic environmental gradient in substrate color, display convergent adaptation of blanched coloration on the gypsum dunes of White Sands National Monument. I investigate the role of gene flow in modulating phenotypic response to selection by quantifying color variation and genetic variation across the ecotone. I find species differences in degree of background matching and in genetic connectivity of populations across the ecotone. Differences among species in phenotypic response to selection scale precisely to levels of genetic isolation. Species with higher levels of gene flow across the ecotone exhibit less dramatic responses to selection. Results also reveal a strong signal of ecologically mediated divergence for White Sands lizards. For all species, phenotypic variation is better explained by habitat similarity than genetic similarity. Convergent evolution of blanched coloration at White Sands clearly reflects the action of strong divergent selection; however, adaptive response appears to be modulated by gene flow and demographic history and can be predicted by divergence-with-gene-flow models.