The pod of killer whales that showed up Thursday, Jan. 30, have only been documented less than 10 times since 1993.

a zoologist and renowned expert in orca acoustics, describes how orcas adapted to the ocean habitat. Watch the video above for the full story. Watch Listening to Orcas on The Nature of Things.

Over time, that name morphed into "killer whales." Scientists don't know whether orcas kill for fun. The marine mammals do some things, like killing and tossing dead porpoises in the air ...

Orcas hunt great white sharks with precision. They flip sharks upside down, inducing paralysis, and eat only their nutrient-rich livers, leaving the rest of the body untouched. Orcas use advanced ...