воскресенье, 5 апреля 2020 г.

Our direct human ancestor Homo erectus is older than we thought

An unusual skullcap and thousands of clues have created a southern twist to the story of human ancestors, in research published in Science.

Our direct human ancestor Homo erectus is older than we thought
A Homo erectus skullcap found northwest of Johannesburg in South Africa has been identified
as the oldest to date. The hominin is a direct ancestor of modern humans, experienced a
changing climate, and moved out of Africa into other continents. The discovery of DNH 134
pushes the possible origin of Homo erectus back between 150,000 and 200,000 years
[Credit: Therese van Wyk, University of Johannesburg]

The rolling hills northwest of Johannesburg are famous for fossils of human-like creatures called hominins. Because of this, the area is known as the Cradle of Humankind.

"During our field school excavations at Drimolen, a student began uncovering a cluster of fragments. We could see that they were parts of a skull. But they weren't immediately identifiable," says Ms Stephanie Baker.

Baker is a researcher and PhD candidate at the Palaeo-Research Institute at the University of Johannesburg. She manages research at the Drimolen fossil site in the Cradle of Humankind where the fragments of DNH 134 were found.

The international team was led by researchers from La Trobe University in Australia and Washington University in St. Louis in the United States.

Fossil forensics

Fossils that are millions of years old often come out of the soil in fragments. The fragments need to be rebuilt before researchers can confidently identify what kind of animal they came from.

"Over the course of the field season more and more fragments were uncovered. We began piecing them together. No one could decide what this skullcap was from, until one night it all came together - and we realised we were looking at a hominin!" she says. They named the skullcap DNH 134.