Whale experts' huge breakthrough

WASHINGTON - Scientists think they have answered a whale of a mystery: How the ocean creatures got so huge so quickly.

A few million years ago, the largest whales, averaged around 5-meter long. That's big, but you could still hold a fossil skull in two hands.

Then seemingly overnight, one type of whale, the toothless baleen, became huge. Modern blue whales get as big as 30 meters, the largest creatures ever on Earth. Its skull is now bigger than a minivan and could probably fit more than five people inside, researchers said.