Data for paper titled "From Inbreeding to Social Behaviour: Exploring Female-Biased Sex Allocation in Microstigmus rosae"

This study uses population genetic analyses to explore the relationship between mating behaviour and sex allocation in Microstigmus rosae. M. rosae (Field 2023) in an incipiently social silk wasp where most nests contain just one adult female, but some contain between 2-4 females, usually daughters of the nest foundress. We first conduct a comprehensive analysis of various genetic indicators of localised mating, including: (a) estimating individual and population level inbreeding coefficients; (b) testing allele frequencies for departures from Hardy–Weinberg equilibrium; and (c) investigating the incidence of diploid male production (a scenario predicted under conditions of inbreeding) through detecting heterozygosity among morphologically male adults. We then estimate the occurrence of mating between siblings. To do this we first inferred the genotypes of each adult female’s mate by comparing her genotype to those of her female offspring. Using these inferred genotypes, we were able to calculate the relatedness coefficients between all female-mate pairs and compare these with the distribution from known sister-brother relationships. We go on to examine the likely role of LMC & LRE by comparing observed sex rations to theoretical predictions of sex allocation theory. We finally examine both precise and sequential sex allocation of offspring by individual adult foundresses, contrasting our observations with those expected under the two principal explanations for female-biased sex ratio adjustment in Hymenoptera (LMC and LRE).