Differential gene expression is correlated with behavioural polymorphism
during collective behaviour in cockroaches
Abstract
Inter-individual variation in the propensity to perform different tasks
is thought to contribute significantly to the success of group-living
organisms. Animals show consistent behavioural differences among them,
referred to as animal personality, which are likely an important
evolutionary driver in animal societies through their influences on
collective actions and thus how these organisms interact with their
environment. At present, however, we have little understanding of the
proximate mechanisms underlying animal personality in animal groups. In
this study, we use a comparative gene expression approach to investigate
the mechanistic basis for personality variation during collective
behaviour in a species with rudimentary societies: the American
cockroach. Our analyses reveal clear differences in gene expression
between behavioural phenotypes with tendencies for short and long
sheltering time. We discuss how the patterns of gene expression might
explain the behavioural differences between individual phenotypes, and
by extension how this might influence the collective performance of
cockroach groups. Our results shed new light on the molecular mechanisms
underlying differences in aggressiveness, dominance and behavioural
plasticity in insect societies, and indicate cockroaches may be a
valuable model for the study of genetic mechanisms underlying the early
steps in the evolution of social behaviour and social complexity.