is it true that humans once had a tail? why is the tailbone called the tailbone?

is it true that humans once had a tail? why is the tailbone called the tailbone? — Asked by Anonymous

Erm, yes and no. See, we evolved from creatures that definitely had a tail, but we are by no means the same species as they were - we wouldn’t even be able to create offspring with them, and they existed more than 5 million years ago.

*Humans* never had a tail, but we have the rudimentary remnants of what was once the tail of our predecessors. It’s still used for an anchor of a couple of the muscles and ligaments of the pelvic floor, but is reduced to the point of being almost useless [vestigial], at least compared to the true tail that many ancestral species possessed.

The “tailbone” is known in science as the “coccyx”, which comes from the Greek word for “cuckoo”. This is because the curved coccyx appears very similar to the beak of a cuckoo, from the side.