Genomic architecture of nestmate recognition cues in the desert ant

Abstract

AbstractNestmate recognition underlies social behaviour in social insects as it forms the basis for cooperation within the colony. Quantitative variation in cuticle hydrocarbons (CHCs) is used for nestmate recognition in ants and other social insects. We carried out a Genome Wide Association Study (GWAS) of CHCs in the desert antCataglyphis nigerby sampling 47 colonies, fully sequencing six workers from each colony and measuring the relative amounts of their CHCs. Under the Gestalt colony odour model, social interactions between nestmates, in which CHCs are being transferred and mixed, are essential in creating a uniform colony CHCs profile. Therefore, we carried out a second GWAS between the colonies and their uniform Gestalt odour by averaging nestmate genotypes and comparing them to their averaged CHCs amounts. Together, these two analyses identified 99 QTLs associated with 18 of the CHCs. Thirteen clusters of two to four QTLs located within 10cM from each other were identified, seven of which contained QTLs from both analyses. We conclude that nestmate recognition, a quantitative and complex colony-level trait, has a genetic component to its phenotypic variation. Our results are in line with the hypothesis that social interactions between nestmates are an important component of the mechanisms that determine the chemical ID of a colony.