Although they are related to killer whales, Commerson’s dolphins are much, much smaller. They reach only 5 ft. (1.5 m) in length, while killer whales can be three to six times that length. Commerson’s often swim upside down, perhaps allowing them to both spot predators that lurk above and prey swimming below. Even these speedy dolphins can’t out swim habitat destruction or pollution though, it’s moving too fast. To help remember to keep trash out of the oceans and recycle instead.