Amongst the countless animal bones collected at Ishango, there were some with notches.
Notches are often considered as count marks, with a line being equivalent to
something. The marks however do not imply the invention of counting.
In fact, it is not very clear ... there are two bones marked very clearly with notches and these could have been used for counting. Then there are a number of other objects with notches, such as harpoons, which could have been for something else.