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TagMaggie Koerth-Baker

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Footwear From Over 75,000 Years Ago? Some Fascinating Hints

Some researchers focus on changes in human foot bones, others on evidence of foot protection on ancient trackways

Recently, possible evidence for footwear dating from the Middle Stone Age, (75,000-150,000 years ago) was reported from South Africa’s Cape Coast. It’s a remarkable claim. After all, the earliest known preserved leather shoe is less than 6,000 years old. But there can be evidence for footwear use other than physical shoes. For example, wearing shoes changes the shape of the human foot. Weight is distributed differently, which affect bones and ligaments. Toe bones, for example, tend to shrink. In 2008, Washington University anthropologist Erik Trinkaus offered evidence based on this observation that humans had begun wearing shoes about 40,000 years ago. As Maggie Koerth-Baker explained at LiveScience, For most of their history, humans had big, thick toe bones. Trinkaus said Read More ›

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The Mirror Test: The Key to a Sense of Self?

When fish and ants pass the test for “a higher sense of self” — but dogs and even kids in some cultures don’t — we should ask some questions

A recent article in the Proceedings of the National Academy of Sciences provided even more evidence that some fish, in particular the tropical cleaner wrasse (Labroides dimidiatus) can recognize and respond to their own images. The fish is best known for cleaning dead skin and parasites off larger fish, without getting eaten. But it turns out they are also remarkable for recognizing themselves in mirrors and photographs. Following up on a 2019 open access paper demonstrating that these fish have that ability, the researchers added a new wrinkle: After the cleaner wrasse passed the mirror test, the researchers showed each fish four photographs: a photo of itself; a photo of an unfamiliar cleaner wrasse; a photo of its own face Read More ›