Bet-hedging via dispersal aids the evolution of plastic responses to unreliable cues

Abstract

Abstract Adaptive plasticity is expected to evolve when informative cues predict environmental variation. However, plastic responses can be maladaptive even when those cues are informative, if prediction mistakes are shared across members of a generation. These fitness costs can constrain the evolution of plasticity when initial plastic mutants use of cues of only moderate reliability. Here, we model the barriers to the evolution of plasticity produced by these constraints and show that dispersal across a metapopulation can overcome them. Constraints are also lessened, though not eliminated, when plastic responses are free to evolve gradually and in concert with increased reliability. Each of these factors be viewed as a form of bet-hedging: by lessening correlations in the fates of relatives, dispersal acts as diversifying bet-hedging, while producing submaximal responses to a cue can be understood as a conservative bet-hedging strategy. While poor information may constrain the evolution of plasticity, the opportunity for bet-hedging may predict when that constraint can be overcome. Abstract Populations may make bad predictions when when using partially reliable cues to track changing environments (left). These mistakes can render plasticity deleterious (s < 0); right) when cue reliability is low, but dispersal among demes spreads out the effects of mistakes and allows the evolution of adaptive plasticity.