POPULATION STRUCTURE ANALYSIS OF FOUR BASAL HIGHER-ATTINES USING BIOINFORMATIC APPROACHES

Metapopulations within the family Formicidae are unique among other animals due to the large colonies they build, and the mating strategies required to fertilize a specialized reproductive caste that will often produce young for the life of the colony. One group of ants, the fungus-gardeners (tribe Attini). The population structure of North American non-leafcutting, fungus-gardening ants has been understudied, especially in the southwest of the United States. Additionally, not much is known about their dispersal biology, so the dynamics of dispersal of these species and how they affect population structure is likewise not well known. To shed light on the structure in these species, four species of non-leaf-cutting ants in the genus Trachymyrmex and Mycetomoellerius were obtained from two other studies for population analysis. The GBS reads of two species sampled in Texas and Oklahoma, Trachymyrmex septentrionalis and Mycetomoellerius turrifex, and two from Arizona, Trachymyrmex arizonensis and Trachymyrmex pomonae, were analyzed using a custom pipeline of bioinformatic software. This pipeline separated the GBS read into two paths: one calling SNPs from the nuclear genome, and the second extracting the mitochondrial genome with MitoFinder. The SNP markers were used to answer the question of population structure by using common tests of structure such as STRUCTURE, FST, AMOVA, and PCA. The extracted mitochondrial markers were used to compare with the nuclear SNPs to determine if there is a discordance between the two-genome suggesting one sex disperses more than the other. The results showed that there is significant structure in T. septentrionalis, M. turrifex, and T. arizonensis; however, no structure was found in T. pomonae. Further, comparison of the nuclear and mitochondrial genomes found evidence of male-biased dispersal within the same T. septentrionalis, M. turrifex, and T. arizonensis.