I believe the evidence is animal bones that show marks from butchery, as well as actual sharpened stone flakes and other things found primarily in what is now K

I believe the evidence is animal bones that show marks from butchery, as well as actual sharpened stone flakes and other things found primarily in what is now Kenya: https://en.wikipedia.org/wiki/Lomekwi https://en.wikipedia.org/wiki/Lomekwi