Genetic Correlations among Developmental and Contextual Behavioral Plasticity inDrosophila melanogaster

Abstract

Correlations among traits, including behaviors, are important because traits that are genetically correlated may not evolve independently. Recently, behavioral-correlations research has expanded to include correlations not only in mean-level behaviors but also in behavioral plasticity, that is, the degree to which individuals change their behavior in response to environmental stimuli. Positive correlations among behavioral plasticities would imply that individuals or genotypes that are behaviorally plastic in one way may also be plastic in other ways; negative correlations could imply trade-offs. Here, we examine aversive odor conditioning (learning) at two time points and plasticity in pupation site selection behavior across substrates in a panel of Drosophila genotypes. These behaviors represent different types of behavioral plasticity: contextual plasticity describes behavioral responses to stimuli that are currently present, while developmental plasticity describes behavioral responses to remembered experiences with stimuli in the recent past. We find that learning scores and plasticity in pupation site selection behavior are positively genetically correlated, representing the first example of a genetic correlation between developmental and contextual plasticity. These findings imply that ecological and evolutionary theories focusing on variation in a single dimension of behavioral plasticity may be incomplete.

Bayesian updating during development predicts genotypic differences in plasticity

“…; Saltz et al. ). Behavior was measured on F1 progeny of crosses between females from each of 116 wild‐derived inbred lines and males from a standard laboratory strain in a “common reference” design (Nuzhdin et al.…”

“…However, there was no indication that the slopes differed for groups measured after 5 minutes versus those measured after 3 hours (Saltz et al. ). Here, we again tested for an effect of time interval on plasticity, but did not find one ( F 1,665 = 0.83, P = 0.36).…”

“…These data were originally collected to address a different question: whether two types of behavioral plasticity (developmental plasticity and contextual plasticity) are correlated with one another across genotypes (Saltz et al. ). As part of that study, Saltz et al.…”

“…We took advantage of existing data on the behavior of D. melanogaster larvae to test predictions of Bayesian models of development that arise from the discrepancy rule. These data were originally collected to address a different question: whether two types of behavioral plasticity (developmental plasticity and contextual plasticity) are correlated with one another across genotypes (Saltz et al 2017). As part of that study, Saltz et al measured the extent to which groups of naïve D. melanogaster larvae from 116 different genotypes were attracted to an odor (ethyl acetate) and then asked how an aversive conditioning training regime (intermittent mild electric shock and no food, in association with ethyl acetate) affected each genotype's response to that odor.…”

Why does the magnitude of genotype‐by‐environment interaction vary?

“…For example, native organisms may fail to respond to invasive predators, resulting in endangerment of native species (Blumstein, 2006;Sih, Trimmer, & Ehlman, 2016). Even within a population's familiar environments, populations lacking sensitivity to a particular stimulus should be unable to evolve responsiveness to that stimulus, inhibiting the potential for G × E. Further, more sensitive genotypes might show greater phenotypic plasticity for multiple phenotypes, producing a positive genetic correlation between different measures of plasticity (Saltz, Hessel, & Kelly, 2017;Saltz, Lymer, Gabrielian, & Nuzhdin, 2017).…”