Authenticated (9/6/03) by WDCS, The Whale and Dolphin Conservation Society.
http://www.wdcs.org
Dorsal fin: The unpaired fin found on the back of the body of fish, or the raised structure on the back of most cetaceans.
Genus: A category used in taxonomy, which is below ‘family' and above ‘species'. A genus tends to contain species that have characteristics in common. The genus forms the first part of a ‘binomial' Latin species name; the second part is the specific name.
Gestation: The state of being pregnant; the period from conception to birth.
Invertebrates: Animals with no backbone.
Melon: In cetaceans, the bulging forehead belonging to a number of species, which contains oil, muscles and nasal passages and is though to focus sound during echolocation.