Disruptive selection and the evolution of discrete color morphs in <i>Timema</i> stick insects.

ABSTRACT: A major unresolved issue in biology is why phenotypic and genetic variation is sometimes continuous, yet other times packaged into discrete units of diversity, such as morphs, ecotypes, and species. In theory, ecological discontinuities can impose strong disruptive selection that promotes the evolution of discrete forms, but direct tests of this hypothesis are lacking. Here, we show that Timema stick insects exhibit genetically determined color morphs that range from weakly to strongly discontinuous. Color data from nature and a manipulative field experiment demonstrate that greater morph differentiation is associated with shifts from host plants exhibiting more continuous color variation to those exhibiting greater coloration distance between green leaves and brown stems, the latte

SUBMITTER: Villoutreix R 

PROVIDER: S-EPMC10065444 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature