It is appropriate that large animals should have large genital organs.

The penis of the hippopotamus and elephant can be several feet in length, and uses have some times been found for such weighty organs other than simple reproduction – the pizzle, for instance, formerly used for flogging, was in fact a bull’s penis. Marshall’s “Physiology of Reproduction” notes that the elephant penis is around 150 cm. in length, a third of which is formed by the pendulous portion. The biggest of all animal penises are to be found among the cetaceans, which include dolphins and whales. In large Rorqual whales the penis can be 10 ft. long with a diameter of up to 1 ft. The whale penis, at its base, consists of two arms attached to the pelvic bones, the arms fuse into the rope-like organ. The penis in cetaceans can generally be retracted into a penile slit.