Whales and Dolphins
Whales, dolphins, and porpoises are members of the Order Cetacea. This is a diverse order and many of it’s members vary in size and features. There are several commonalities all members share that make them well-suited to their watery home. Cetaceans have elongated, streamlined bodies that are generally hairless. They lack any hind limbs and their fore limbs have been modified into flippers. Most cetaceans also have a dorsal fin. Rather than a “nose”, cetaceans have their nostrils in the form of a blowhole on the top of their heads.
The Cetacea consists of two suborders:
Odontoceti: The Odontocentes are the toothed Cetaceans. This suborder contains more than 70 unique species of animals. This includes ocean dolphins, river dolphins, porpoises, sperm whales, beaked whales, and monodontids (Narwhal and Beluga), making it a very diverse order.
Mysticeti: The Mysticeti are the baleen whales. This order contains only around 13 species, making it much less diverse.
These groups are distinguished by two features. Odontoceti have teeth and one blowhole, while Mysticeti have baleen and two blowholes.
The Cetacea consists of two suborders:
Odontoceti: The Odontocentes are the toothed Cetaceans. This suborder contains more than 70 unique species of animals. This includes ocean dolphins, river dolphins, porpoises, sperm whales, beaked whales, and monodontids (Narwhal and Beluga), making it a very diverse order.
Mysticeti: The Mysticeti are the baleen whales. This order contains only around 13 species, making it much less diverse.
These groups are distinguished by two features. Odontoceti have teeth and one blowhole, while Mysticeti have baleen and two blowholes.
Gulf of Maine Research Institute. (2013). Marine Mammal Taxonomy. Retrieved from: http://octopus.gma.org/marinemammals/natural_history_facts.html
Reeves, R. R., Stewart, B. S., Clapham, P. J., Powell, J. A. (2002). Guide to Marine Mammals of the World. New York, New York: National Audubon Society.
Reeves, R. R., Stewart, B. S., Clapham, P. J., Powell, J. A. (2002). Guide to Marine Mammals of the World. New York, New York: National Audubon Society.
Updated: December 2, 2014