HALLMARK TRAITS of the human body did not all arise anew in our species. Instead they emerged piecemeal in our forebears over millions of years. Many of these traits seem to have helped support two defining trends in our evolution: upright locomotion and tool use.
More on this topic: Our Secret Evolutionary Weapon: Monogamy
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.