Evolution of a Polyphenism by Genetic Accommodation
Abstract
Polyphenisms are adaptations in which a genome is associated with discrete alternative phenotypes in different environments. Little is known about the mechanism by which polyphenisms originate. We show that a mutation in the juvenile hormone-regulatory pathway in Manduca sexta enables heat stress to reveal a hidden reaction norm of larval coloration. Selection for increased color change in response to heat stress resulted in the evolution of a larval color polyphenism and a corresponding change in hormonal titers through genetic accommodation. Evidently, mechanisms that regulate developmental hormones can mask genetic variation and act as evolutionary capacitors, facilitating the origin of novel adaptive phenotypes.
- Publication:
-
Science
- Pub Date:
- January 2006
- DOI:
- 10.1126/science.1118888
- Bibcode:
- 2006Sci...311..650S
- Keywords:
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- EVOLUTION