Sperm whale Sperm whale The sperm whale ("Physeter macrocephalus") or cachalot is the largest of the toothed whales and the largest toothed predator. It is the only living member of genus Physeter and one of three extant species in the sperm whale family, along with the pygmy sperm whale and dwarf sperm whale of the genus "Kogia". The sperm whale is a pelagic mammal with a worldwide range, and will migrate seasonally for feeding and breeding. Females and young males live together in groups, while mature males (bulls) live solitary lives outside of the mating season. The females cooperate to protect and
Blue whale penis immature categorized whale was and the smallest penis of a mature whale was . By comparison the average blue whale penis is nearly 3 times the size of that of a sei whale. Specimen measurements indicate that a blue whale measuring in length had a vestigial mammary slit of width and length, with a penis measurement of . In another specimen in which the length of the whale was and weighed 50.9 metric tons, the brain weighed only . The Icelandic Phallological Museum has a portion of a blue whale's penis measuring long and weighing , which "Iceland Review" has