This friendly-faced cetacean has an unfriendly name: Killer whale. If you prefer, though, you can call it by its other name: orca. Orcas are large, black and white dolphins that eat birds, fish, and other marine mammals such as seals, sea lions, and other whales. Their teeth are around four inches long, which means they can do a lot of damage. However, their large teeth aren't their only strength. Orcas are intelligent and social creatures with excellent memory, all of which comes in handy when hunting prey. Found swimming in ocean waters around the world, orcas, oftentimes, live in groups called pods, which generally consist of two or three generations of related females and their offspring. Depending on how long they live, orca mothers may even become grandmothers when their son or daughter has a calf, or baby orca, of their own. Orcas can live for a long time too--anywhere from 50 to 100 years. Since female orcas typically outlive male orcas, the chance of a female living long enough to become a grandmother is even more likely.