A 90,000-year-old bone knife hints special tools appeared early in Africa

Africa’s Stone Age was also a Bone Age.

Ancient Africans took bone tools to a new level around 90,000 years ago by making pointed knives out of animals’ ribs, scientists say. Before then, bone tools served as simpler, general-purpose cutting devices.  

Members of northern Africa’s Aterian culture, which originated roughly 145,000 years ago, started crafting sharp-tipped bone knives as fish and other seafood increasingly became dietary staples, researchers suggest online October 3 in PLOS ONE. The new find supports the view that strategic planning for survival and associated changes in toolmaking emerged much earlier in human evolution than has traditionally been assumed.

Excavations inside Dar es-Soltan 1 cave, near Morocco’s Atlantic coast, uncovered the bone knife in 2012, says a team led by geoarchaeologist Abdeljalil Bouzouggar of the National Institute of Archaeological and Heritage Sciences in Rabat, Morocco, and biological anthropologist Silvia Bello of the Natural History Museum in London. The knife’s base and its broken-off tip were embedded in sediment that dates to about 90,000 years ago.

To make the knife, ancient humans first removed part of a cattle-sized animal’s rib and cut it in half lengthwise. Toolmakers then scraped and chipped one of the halves into a nearly 13-centimeter-long knifelike shape.

Light damage to the find indicates that Aterians used the knife primarily to cut soft material, such as leather, Bello says. “Whatever its use, this tool was produced by very skilled manufacturers.”

Two knife-shaped bone tools previously found at another Aterian site in Morocco lack precise age estimates, but are about as old as the Dar es-Soltan 1 discovery, the researchers estimate.

Specialized bone tools found more than 20 years ago in central Africa also date to 90,000 years ago (SN: 4/29/95, p. 260). Other parts of Africa witnessed shifts in stone-tool making and other behaviors by that time (SN: 10/13/18, p. 6).