Genetic variation in social environment construction influences the development of aggressive behavior in Drosophila melanogaster

Abstract

Individuals are not merely subject to their social environments; they choose and create them, through a process called social environment (or social niche) construction. When genotypes differ in social environment-constructing behaviors, different genotypes are expected to experience different social environments. As social experience often affects behavioral development, quantitative genetics and psychology theories predict that genetic variation in social environment construction should have an important role in determining phenotypic variation; however, this hypothesis has not been tested directly. I identify multiple mechanisms of social environment construction that differ among natural genotypes of Drosophila melanogaster and investigate their consequences for the development of aggressive behavior. Male genotypes differed in the group sizes that they preferred and in their aggressive behavior; both of these behaviors influenced social experience, demonstrating that these behaviors function as social environment-constructing traits. Further, the effects of social experience-as determined in part by social environment construction-carried over to affect focal male aggression at a later time and with a new opponent. These results provide manipulative experimental support for longstanding hypotheses in psychology, that genetic variation in social environment construction has a causal role in behavioral development. More broadly, these results imply that studies of the genetic basis of complex traits should be expanded to include mechanisms by which genetic variation shapes the environments that individuals experience.

The Power of Infochemicals in Mediating Individualized Niches

“…Population densities can be modulated by aggression pheromones, for example, in Drosophila melanogaster [33,38]. The fine-tuned responses to different pheromone concentrations mediate…”

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

“…For example, different cottonwood ( Populus ) genotypes differ in the concentration of tannins in their leaves, altering the chemical composition of the soil below them where the leaves decompose (Driebe & Whitham, ; Whitham et al., ). In Drosophila melanogaster , social groups differing only in the genotype of a single male have different group dynamics (Saltz, , ; Saltz, Geiger, Anderson, Johnson, & Marren, ). Siblings with different personalities may receive different parental care, even from the same parents (Hayden et al., ; Plomin et al., ).…”

“…Variation in plasticity due to large-effect loci will result in greater magnitude G × E than variation in plasticity due to small-effect loci Drosophila melanogaster, social groups differing only in the genotype of a single male have different group dynamics (Saltz, 2013(Saltz, , 2017Saltz, Geiger, Anderson, Johnson, & Marren, 2016). Siblings with different personalities may receive different parental care, even from the same parents (Hayden et al, 2009;Plomin et al, 1977).…”

“…In general, one of the most important steps for investigating G × E when genotypes vary in niche-constructing traits is to simply acknowledge this possibility. Directly measuring the experiences of each individual, rather than assuming that all individuals in the same experimental treatment experience the same environment, can substantially improve our interpretation of experiments designed to measure G × E (Saltz, 2017).…”

Kin recognition and co‐operative foraging inDrosophila melanogasterlarvae

“…Although engaging in such competition (be it directly or indirectly) is a common response to scarcity, it is not an inevitable outcome. Indeed, in some species, rather than act antagonistically towards others (Richardson, Mitchell, Reagel, & Hanks, 2010, Saltz 2016, some individuals will engage in co-operative behaviours in order to acquire more resources (Dugatkin, 1997). Such behaviours come at a cost to the interacting individuals but can yield a net benefit to the participants.…”