Our genomes, the DNA in our eukaryotic cells and our microbiomes, the prokaryotic life that coexist within us, constitute our genetic heritage. We inherited them from our parents but these elements have been with us throughout human evolution. They allow us to take a peek into our past. Who were our ancestors? What did they look like? What did they eat? How did they live? They are also tightly linked with our health and wellness. We study genomes and microbiomes to understand the history and health of humans as well as animals around us.