A number of my SciBlings (and their commenters) try to explain:
Janet
Chad
Martin
PhysioProf
DrugMonkey
Brian Switek
Alice
Jeremy Bruno
Grrrrrl
More like this
This sucker was filmed in the Gulf of Mexico swimming among the oil rigs!!! It propelled itself with undulations of its dorsal fin and looks a lot like a sea serpent.
We discussed this a few months on Nature Network. The Blog Monster is still hungry.
Answered here.