Changing Planet

Ancestors Lived in Cave Two Million Years Ago

cave-lede.jpg

Last seen two million years ago, one of the early stone tools discovered in Wonderwerk Cave.

Photo by M. Chazan

The earliest evidence for cave occupation by hominids has been discovered in South Africa.

Stone tools found at the bottom level of Wonderwerk Cave show that human ancestors were in the cave two million years ago, earlier than thought, according to an international research team led by Michael Chazan, director of the University of Toronto’s Archaeology Centre.

Geological evidence indicates that the tools were deposited in the cave by ancestors, not washed into the site from the outside, the team announced last week.

“There were a number of species of hominids in southern Africa two million years ago,” according to a University of Toronto news release. “The most likely candidate as the manufacturer of the stone tools found at Wonderwerk is Homo habilis.”

cave-1.jpg

View of the Interior of Wonderwerk Cave

Photo by Royden Yates

The Wonderwerk Cave discoveries are close in age to the very earliest known stone tools and similar in date to the bottom levels at Olduvai Gorge, Tanzania, according to the release. The oldest known stone tools from sites in Ethiopia date to 2.4 million years.

To determine reliable dates for the age of the tools discovered in Wonderwerk Cave scientists used an unusual combination of tests.

Hagai Ron of the Hebrew University of Jerusalem took more than 50 small samples of soil from the cave where the tools were found. A method called paleomagnetic dating measured changes in the earth’s magnetic field across a sequence of samples to calculate the age of the soil around the tools.

cave-4.jpg

Hagai Ron taking samples from the section at Wonderwerk Cave.

Photo by M. Chazan

Ari Matmon, also from the Hebrew University, took soil samples for a different test known as cosmogenic burial age. These samples were sent to an atomic accelerator in the United States where a procedure to measure isotopes, much like the method used in carbon dating, was carried out.

“The combination of stone tools indicating the presence of human ancestors and the dating of the level leads to the conclusion that human ancestors were in the cave two million years ago,” the University of Toronto’s Archaeology Centre stated.

Archaeological investigations of the Wonderwerk cave — a South African National Heritage site due to its role in discovering the human and environmental history of the area — began in the 1940s and research continues to this day.

The cave formed by water action in dolomite rocks more than two billion years old, some of the oldest rock on Earth. The age of the cave itself is not known.

cave-2.jpg

Map of Wonderwerk Cave generated by 3-D scanning carried out by Heinz Ruther of the Department of Geomatics, University of Cape Town. The inset shows a view of the front excavation area where the dating project took place.

Forty years in U.S., UK, and South African media gives David Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. He has 120,000 followers on social media. David Braun edits the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directs the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. Follow David on Facebook  Twitter  LinkedIn
  • 漠刀绝尘

    Hey, I read a lot of blogs on a daily basis and for the most part
    people lack substance but
    I just wanted to make a quick comment to say GREAT blog!…..
    I’ll be checking in on a regularly now….
    Keep up the good work!
    http://www.nike-star-shoes.net nike shoes

  • jessie31

    Wow…our ancestors lived in cave earlier than we had expected previously!!

About the Blog

Researchers, conservationists, and others share stories, insights and ideas about Our Changing Planet, Wildlife & Wild Spaces, and The Human Journey. More than 50,000 comments have been added to 10,000 posts. Explore the list alongside to dive deeper into some of the most popular categories of the National Geographic Society’s conversation platform Voices.

Opinions are those of the blogger and/or the blogger’s organization, and not necessarily those of the National Geographic Society. Posters of blogs and comments are required to observe National Geographic’s community rules and other terms of service.

Voices director: David Braun (dbraun@ngs.org)

Social Media