Comment: Appendix...

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Appendix...

...is thought to actually be a kind of factory for promoting growth of good bacteria; coccyx helps you sit down comfortably by providing a third point of impact and lots of muscles and tendons attach to it such as those controlling your pelvic floor muscles which help you know when to go to the toilet and those that help you walk.

As I understand, the term 'vestigial' is avoided these days by biologists to avoid the embarrassment of having to make a retraction later.