MICROSATELLITE DNA MARKERS REVEAL DETAILS OF SOCIAL-STRUCTURE IN FOREST ANTS

We developed microsatellite loci from the genome of the temperate fore st ant Myrmica punctiventris and used them to study colony genetic str ucture. We report here primer sequences for three new microsatellite l oci, and also show that previously published primers isolated from a c ongener amplify loci in our study species. Successful cross-priming of loci in four other ant species further illustrates that investigators may now be able to sidestep the labour of developing new microsatelli te systems. The microsatellite data allowed us to estimate coefficient s of relatedness far more precisely than was possible from previous al lozyme work. Furthermore, we obtained evidence of complex colony struc ture in this population: while overall colonies showed a relatedness s tructure that is consistent with values expected for a single, once-ma ted queen (Hamilton 1964), some nests contained worker-laid males, whi le others included members of at least two families. We used these dat a to examine reproduction as a function of genetic structure, and foun d evidence of sex ratio compensation in this species: nests containing worker-laid males allocated more energy to reproduction and had stron gly male-biased allocation ratios relative to others in the population .