Cetacia is a novel by French-Canadian writer Mel Gosselin.
cetacia.... or something like that
No. It means Wales, which is a British country now part of England. Whales are Cetacia.
Just a thought but a few characteristics would be Warn Blooded Live Young (not exclusive to mammals but a big characteristic, I think one or two mammals lay eggs but that's it) Air Breathing (definitely not specific to mammals but distinct from alot of sea creatures) Produce Milk (I think this is exclusive to mammals) 4 Chambered Heart Belong to the order of Cetacia (Whales, Dolphins and Porpoises), a mammalian placental order