Some seek their roots to try to understand who they are. Carles Lalueza-Fox (Barcelona, 1965) searches for them to decipher where we come from and better understand our past as a species. For more than two decades, this paleogeneticist from the Institute of Evolutionary Biology (IBE-CSIC-UPF) and current director of the Museum of Natural Sciences of Barcelona has been reading the history of humanity in ancient DNA and is one of the world's leading experts. He has contributed to demonstrating that modern humans carry Neanderthal DNA and has reconstructed migrations and interbreeding of prehistoric populations. He has just published Identidad (Crítica) where he delves into swampy terrain: what DNA can explain about who we are and what it cannot.