Do you want one animal? That's a weird question. Are you sure it isn't homework?
Well, anyway, here's an answer:
A whale. (The person before me also suggested a seahorse.)
But there are tons more! A lot of fish have vertebrae too!
it is a animal that lives in the ocean
what is the smallest animal in the Arctic Ocean
manatees
anchovies
plankton is a microscopic animal that lives in the ocean.
Snail fish
blue whale
Fish
Nothing
An ocean animal would be an urchin. It begins with the letter U.
if it lives on land it is terrestrial if it lives in trees aboreaol if it lives in the water it is aquatic if it lives in the ocean it is marine
A sea creature is an animal that lives in the ocean.