How can one possibly explain great whales swimming the seas having originated through some evolutionary process, beginning with an invertebrate (animal without a backbone) which somehow develops vertebrae (a backbone) to become a fish and then these fish decide to move to land, so they drop off their fins and evolve front legs and develop a tail and hind legs and change their breathing from their gill slits to their noses to become amphibians, and these amphibians change their jelly-like eggs to shelled eggs, strengthen their jawbones, and evolve into reptiles, and these reptiles shift some of the bones of their jaws into their ears, and evolve into mammals, and some of these mammals decide to march back into the sea and so they decide to evolve off their hind legs and change the shape of their tail to a tail fin and transform their front legs into fins, change their breathing from their noses to the blowhole on top of their head, and march back into the sea to become whales.
(vertebrae; to become; a fish) (they; develop; a tail and hind legs) (they; evolve; front legs) (great whales swimming the seas; having originated; ) (they; drop off; their fins)
vertebrae they they great whales swimming the seas they
to become develop evolve having originated drop off
a fish
a tail and hind legs
front legs
their fins