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Biology

What does our tailbone tell us about evolution?

Quick fact

The coccyx (tailbone) is the fused vestige of a tail that our mammalian ancestors used for balance, movement, and communication—now it's an attachment point for pelvic muscles and tendons.

Why this is interesting

You have a tail—it's just shrunk to a small, fused bone at the bottom of your spine, a relic from our tree-dwelling ancestors that lost its purpose but not its presence.