What if one of our oldest ideas about ancestry is simply wrong? Harvard geneticist David Reich argues that ancient DNA has exposed the myth of purity and uncovered a far messier history of who we are and where we came from.

Questions about our origins, biologically, chemically, and cosmically, are the most profound ones we can ask. Here are today's best answers.

New research challenges old assumptions about the evolution of the human brain.

A new method of mapping migration factors in erratic movements and changing climate.

There were at least eight other human species, some of whom existed for far longer than we have. Who were they?

More humans are being born with a third arm artery, an example of microevolution happening right before our eyes.

Planet Earth has been around for over 4.5 billion years, but humans? For 99.998% of our planet's history, humans were nowhere to be found.