Ancient skull: A Homo erectus skullcap found northwest of Johannesburg has been identified as the oldest to date. The hominin, a direct ancestor of modern humans, moved out of Africa into other continents.
Stone Age chewing gum: This piece of birch pitch was chewed by a girl who lived 5,700 years ago in what's now Denmark. Geneticists were able to sequence her genome and oral microbiome from the substance. It was the first time human genetic material had successfully been extracted from something besides human bones.
Prehistoric Picasso: Maxime Aubert and Adam Brumm were part of the team that made the discovery of the world's oldest rock art found in a cave in Sulawesi, Indonesia.