Disruptive selection and the evolution of discrete color morphs in Timema stick insects.
Sci Adv
; 9(13): eabm8157, 2023 03 31.
Article
em En
| MEDLINE
| ID: mdl-37000882
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 latter of which generates strong disruptive selection. Our results show how ecological factors can promote discrete variation, and we further present results on how this can have variable effects on the genetic differentiation that promotes speciation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Deriva Genética
/
Neópteros
Limite:
Animals
Idioma:
En
Revista:
Sci Adv
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
França