The oldest mathematical instrument is the Lebombo bone, a baboon fibula used as a measuring device.
It was discovered in the Lebombo Mountains of Swaziland. The device is at least 35,000 years old. It could have been used as a measuring stick or moon cycle measure. It had 29 markings that also correspond to the lunar cycle. The bone may be connected to the Kemetic/ Egyptian god Djehuty (“Tehuti” or “Toth”), was later depicted as a baboon (also an ibis), and associated with the moon, math, writing and science.