Human Use of Fire Much Earlier Than Previously Thought
April 3, 2012
The earliest evidence of the intentional use of fire by early humans has been found at Wonderwerk Cave, a prehistoric site about 105 miles (170 kilometers) northwest of Kimberley in the Northern Cape province of South Africa. The finding suggests that early humans used fire as much as 400,000 years earlier than scientists had previously believed. Archaeologist Francesco Berna of Boston University and his colleagues described ash from burnt grass and leaves in cave sediments (earth, stones, or other matter suspended in or deposited by water, wind, or ice) that have been dated to about 1 million years ago. Stone tools and other remains at the site are evidence that early humans occupied the cave. Tiny fragments of burnt bone were also found, suggesting early humans used the fire to cook meat. The team published their findings online on April 2, 2012, in the Proceedings of the National Academy of Sciences.
The sediments containing burnt material at Wonderwerk Cave were excavated from about 98 feet (30 meters) inside the cave. These same layers also contained double-edged stone tools called hand-axes, which archaeologists believe originated with the early human ancestor Homo erectus. Previously, the oldest accepted evidence of the use of fire was found in a cave called Zhoukoudian that H. erectus occupied between 600,000 and 400,000 years ago near what is now Beijing, in northeastern China. Stone tools and the remains of more than 40 H. erectus individuals were found in that cave, along with ash and burnt animal bones.
However, ash deep inside a cave is not proof that early humans used fire. The archaeologists at Wonderwerk Cave needed to show that the burnt remains were the result of human activity and not natural processes. Examined under a microscope, the fragments of burnt grass and leaves from Wonderwerk Cave have sharp edges. This suggests the fire was burned inside the cave. Ash from wildfires blown or washed by floods into the cave would have edges worn smooth by erosion. The amount of ash and burnt remains found in various layers of sediment indicates there were repeated episodes of burning. This suggests that the cave was a site regularly used by early humans to shelter and cook food.
The controlled use of fire was a major accomplishment in human history. Fire enabled our early ancestors to stay warm in cold environments and helped keep dangerous predators away. Cooking some foods with fire also enhances their nutritional value and makes them easier to digest. Many anthropologists believe that H. erectus was probably the first human being to master the use of fire. A few other sites in Africa that preserve evidence of fire date as far back as 1.5 million years ago. However, many archaeologists have expressed doubts about these sites. They point out that they could have been formed by such natural means as wildfires or lightning strikes.
Additional World Book articles:
- Cave dwellers
- Prehistoric people
- Stone Age
- A New Perspective on Primates (a special report)