Interproximal grooving of teeth

<div>The oldest example of the use of the toothpick, a technological and cultural artifact, evidenced by interproximal grooves, comes from an upper first premolar of one of the earliest representatives of the genus Homo, L 894-1 -1.84 million years old, from the Ethiopian site Omo. Studies of these grooves, location and longitudinal polish and striations similar to those documented in prehistoric and modern populations, have led to a consensus that toothpick may be one of the earliest tools devised by humanity.</div><div>