Well, crows in Japan learned to drop nuts into traffic so that cars would crush them, and then wait for the light to go red before collecting the food.
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The crows here in N. Calif do the same thing: Drop walnuts from my neighbor’s tree into the road, then wait till they are conveniently crushed by passing traffic. I wonder: do great (crow) minds think alike, or was this technique passed from crow to crow until it reached around the world?
They did observe it spreading to other crow populations in Japan, and being passed down generation to generation, so they do seem to be teaching each other.