iPhones, staplers, aluminum foil. Humans are surrounded and defined by their technologies. We might even say: Technology makes us human.
But that’s not quite true, because we know that other animals employ and deploy tools, too. Primates use twiggy Roto-Rooters to search for bugs. All sorts of creatures make homes for themselves; bowerbirds sculpt fantastical ones.
And now we know it’s not quite true either, historically. New archeological evidence indicates that our ancestors used a certain kind of tool—a “complex tool,” in the parlance of anthropologists—when they were still our ancestors.
That is: They threw spear-tipped javelins, to catch and kill animals.
We know because archeologists just located the stone tips of the arrows in the Rift Valley of central Ethiopia. Cracks in the stone indicate that they were likely thrown (as opposed to used for stabbing or bludgeoning prey), and they’re too old to be used by modern humans.
That’s because the tips are 280,000 years old. Homo sapiens—us—appear first in Africa about 200,000 years ago. The tips were used, instead, by the homo heidelbergensis, the dominant hominid from about 1.3 million years ago to 600,000 years ago.
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