Chapter 11 : Genetic Cooperation and Conflicts in Mating and Social Systems

Behavioral ecology (Krebs 1987) has a rich tradition of calling tradeoffs a cost-benefit. We can synonymize cost-benefit analysis with the notion of a life history trade-off introduced in chapter 3, because in some cases even social system trade-offs have been linked to the pleiotropic effects of one gene on two or more traits. As we will see below, in greenbeard dynamics, which arise from three greenbeard traits envisioned by Hamilton (1964) (the signal, signal recognition of self [or non-self], signal recognition elicits donation to self [or nasty to non-self]), the evolution of a beneficial self-cooperative strategy allows alternative strategies to invade and exact a social cost to cooperation that we call altruism. A consideration of social trade-offs allows us to come up with a synthetic view of the genetic sources of constraints on behavioral systems. In particular, other trade-offs, besides the primary life history trade-offs (Chapter 3) arise in the context of mating system dynamics and social system dynamics. Trade-offs in behavioral systems impact and interact with life history trade-offs. These many axes of constraint keep behavioral systems bounded. However, trade-offs also create the opportunity for novel social adaptations to arise, referred to as alternative behavioral strategies. Thus, the goal in this chapter is to not only elaborate on adaptation and constraint in life history and behavior, but also the sources of evolutionary novelty in social systems.