The <i>Drosophila melanogaster foraging</i> gene affects social networks

<i>Drosophila melanogaster</i> displays social behaviors including courtship, mating, aggression, and group foraging. Recent studies employed social network analyses (SNAs) to show that <i>D. melanogaster</i> strains differ in their group behavior, suggesting that genes influence social network phenotypes. Aside from genes associated with sensory function, few studies address the genetic underpinnings of these networks. The <i>foraging</i> gene <i>(for)</i> is a well-established example of a pleiotropic gene that regulates multiple behavioral phenotypes and their plasticity. In <i>D. melanogaster,</i> there are two naturally occurring alleles of <i>for</i> called rover and sitter that differ in their larval and adult food-search behavior as well as other behavioral phenotypes. Here, we hypothesize that <i>for</i> affects behavioral elements required to form social networks and the social networks themselves. These effects are evident when we manipulate gene dosage. We found that flies of the rover and sitter strains exhibit differences in duration, frequency, and reciprocity of pairwise interactions, and they form social networks with differences in assortativity and global efficiency. Consistent with other adult phenotypes influenced by <i>for</i>, rover-sitter heterozygotes show intermediate patterns of dominance in many of these characteristics. Multiple generations of backcrossing a rover allele into a sitter strain showed that many but not all of these rover-sitter differences may be attributed to allelic variation at <i>for.</i> Our findings reveal the significant role that <i>for</i> plays in affecting social network properties and their behavioral elements in <i>Drosophila melanogaster</i>.