Recent advances in Next Generation Sequencing technologies and the subsequent rise in microbiome research has shown that symbiotic microbes are ubiquitous and play vital functions that impact host health; yet we lack a general understanding of how microbes evolve, and what impacts such evolution has on the host. The Batstone Lab combines quantitative genetics, bioinformatics, and mutualism theory to study how mutualistic microbes adapt to hosts, to understand how changing abiotic conditions modulate such adaptation, and to identify the genomic mechanisms underlying symbiosis evolution.