Monday, April 11, 2005

444: Bivoltinism as an Antecedent to Eusociality in the Paper Wasp Genus Polistes -- Hunt and Amdam 308 (5719): 264 -- Science

Bivoltinism as an Antecedent to Eusociality in the Paper Wasp Genus Polistes -- Hunt and Amdam 308 (5719): 264 -- Science:

To learn the evolutionary trajectories of caste differentiation in eusocial species is a major goal of sociobiology. We present an explanatory framework for caste evolution in the eusocial wasp genus Polistes (Vespidae), which is a model system for insect eusocial evolution. We hypothesize that Polistes worker and gyne castes stem from two developmental pathways that characterized the bivoltine life cycle of a solitary ancestor. Through individual-based simulations, we show that our mechanistic framework can reproduce colony-level characteristics of Polistes and, thereby, that social castes can emerge from solitary regulatory pathways. Our explanatory framework illustrates, by specific example, a changed perspective for understanding insect social evolution.

Testable evolutionary hypotheses. Computer simulations show that this mechanism is feasible, and research on wasps will reveal whether it explains the evolution of true sociality in the wasps.