Lebombo Bone

The artifact known as the Lebombo Bone, is a fibula or calf bone of a baboon, with 29 incised markers. It was found by Peter Beaumont in an archaeological site called "Border Cave" located in the Lebombo Mountains stretching between South Africa and Eswatini, formerly known as Swaziland. Radiocarbon datings place the bone at an age of 44,200-43,000 years. The 29 notches are made by several distinct cutting edges, hinting at a role in a participation ritual and it resembles calendar sticks used by Bushmen clans in Namibia.

The number of notches suggests that it could have been used as a lunar phase counter, potentially to keep track of menstrual cycles. This would make the women who used it the first known mathematicians, over 30,000 years before the birth of written mathematics around 3500BC, and 25,000 years before the earliest use of tools for accounting in 8000-7000BC. However, the bone is broken off on one side, so it cannot be known for certain that 29 notches were the total amount.