Special Thanks
Our thanks to the folks at Ocean Alliance and Sea World Orlando for the tremendous photos they provided for this article.
In the world's great whale tales, including Herman Melville's "Moby Dick," the storytellers are preoccupied with one particular whale attribute: awesome size. Many whale species are staggeringly enormous. The blue whale, for example, can grow to 100 feet (30 m) long, about the height of a 10-story building, and can weigh as much as 150 tons (300,000 lb or 136077.7 kg). Its heart alone is the size of a small car, and there's enough room on its tongue for 50 people. It is the largest known animal in Earth's history.

Photo courtesy Iain Kerr, Ocean Alliance
A humpback whale, one of the most magnificent whale species. Humpbacks are known for their intelligence, playfulness and elaborate vocalizations.

But despite their monumental proportions, the most phenomenal thing about whales isn't how big they are: It's the way they live. Whales are mammals -- warm-blooded, air-breathing creatures -- but they spend their entire life in the ocean. In this article, we'll look at the remarkable adaptations that make this possible. We'll also explore the mysterious behavior of whales, and we'll investigate the history of commercial whaling and whale conservation.