The porpoise, along with dolphin and the whale, all belong to the mammalian order Cetacea. Porpoise and dolphin are members of different families, but there is no sharp scientific distinction between them. The porpoise is generally smaller and does not possess the characteristic 3" bottle-nose of the dolphin. The playful porpoise is gray or black with a slightly lighter underside. It can live to the age of 30, occasionally attaining a length of 12', although most are in the 6'-8' range.
A system of echolocation - much like sonar - directs them in their travels. Porpoises have no sense of smell. Keen eyesight, remarkable hearing, and a wide variety of sounds (barks, clicks and whistles) make the porpoise an especially interesting subject to study. Test have determined the intelligence level of porpoises to be between that of a dog and that of the highest-known intellect in the nonhuman animal world, the chimpanzee. Some even place the porpoise above the chimp!
Historically, sailors have taken the presence of porpoises near their boats as a sign of good luck.
Porpoises:
Burmeister's Porpoise (Phocoena spinnipinnis)
Dall's Porpoise (Phocoenoides dalli)
Finless Porpoise (Neophocaena phocaenoides)
Harbour Porpoise (Phocoena phocoena)
Spectacled Porpoise (Australophocaena dioptrica)
Vaquita (Phocoena sinus)
