Early humans in East Africa used hammerstones to strike stone cores and produce sharp flakes. For more than 2 million years, early humans used these tools to cut, pound, crush, and access new foods—including meat from large animals. ... Scientists have made experimental stone tools and used them to butcher modern animals. the most basic stone implements made by early humans. These Oldowan tool kits include hammerstones, stone cores, and sharp stone flakes. By about 1.76 million years ago, early humans began to make Acheulean handaxes and other large cutting tools.