Phenotypic plasticity
Phenotypic plasticity—the ability of individual genotypes to produce varying phenotypes based on the environment (West-Eberhard 2003)—provides an alternative mechanism for coping with climate change that is more rapid than evolutionary adaptation. However, because plasticity impedes natural selection on genetically based variation, it may ultimately inhibit population persistence under long-term directional change (Gienapp et al. 2008, Whitman and Agrawal 2009, Chevin et al. 2010, 2013, Merilä and Hendry 2014). For mosquitoes, potentially important plastic responses include changes in activity patterns, biting behavior, or microhabitat selection, thermal acclimation, and initiation of dormancy, as reviewed below (and see Appendix C: Table S3). Phenotypic plasticity may itself vary across genotypes and thus could evolve in response to environmental change, but experimental evidence that this is possible is lacking (DeWitt et al. 1998, Scheiner and Berrigan 1998, Stinchcombe et al. 2004). Overall, mosquitoes possess a variety of potential plastic responses, but the capacity for these responses to increase thermal tolerance, their potential fitness costs, and how these plastic responses might interact with the process of evolutionary adaptation remain poorly understood. Below, we review current knowledge of different potential plastic responses.