What animals in the ocean are extinct?

There are very many extinct species of whales, porpoises, and dolphins. Whales actually descend from a prehistoric dog that lived in the Middle East. Many species of whale thrived and became extinct between the doglike whales millions of years ago and the ones we have today.

Here is a page that has different species of whales and includes a list of extinct whales about 3/4 of the way down.

http://en.wikipedia.org/wiki/List_of_whale_species

Happy to help,

Anon