Adam's

The baculum (also penis bone, penile bone or os penis) is a bone found in the penis of most mammals. It is absent in humans. It is used for copulation and varies in size and shape by species. Its characteristics are sometimes used to differentiate between similar species. The word originally meant "stick" or "staff" in Latin. Although many mammals have a penile bone, humans do not; the rigidity of the erection is provided entirely through blood pressure in the corpus cavernosum. Examples of animals with ...

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