Early humans still had great ape-like brains, according to a new study that found modern humans evolved to have our “advanced” thinking organs relatively recently, between 1.7 million and 1.5 million years ago.

This means that the unique brain of modern humans (Homo) developed more than 1 million years after the Homo genus arose, and after the first Homo erectus migrated out of Africa, according to the study, published online Thursday (April 7) in the journal Science.