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Add the humble toothpick to the list of the earliest human inventions.
Homo erectus used toothpicks 1.8 million years ago, says Peter Ungar of the
University of Arkansas in Fayetteville. A tooth from the famous Olduvai Gorge
site in Tanzania bears a series of tiny parallel lines scraped by a sharp, thin
object pushed into the narrow space between teeth, he told a meeting of the
American Association of Physical Anthropology last week. He believes early
humans adopted toothpicks when they started eating meat. Many later human teeth
have similar marks, but modern chimpanzees and gorillas do not use
toothpicks.