Perucetus colossus, an ancient whale that lived 38 million years ago, is a new contender for the heaviest animal ever. Plus, four key questions on the new wave of anti-obesity drugs.

Giant sharks, massive sea turtles, and enormous whales shared this crowded ecosystem. Livyatan’s reign was made possible by the abundance of large prey, including other whales and gigantic squid.

NEW YORK — There could be a new contender for heaviest animal to ever live. While today’s blue whale has long held the title, scientists have dug up fossils from an ancient giant that could ...

The blue whale is not only currently the biggest animal on Earth, but scientists long thought that it might be the largest animal to have ever lived. Now fossils unearthed in Peru suggest a giant ...

19 1/2-foot, 103-pound specimen may provide clues to protect endangered whales Looking something like an alien being from the movie "Independence Day," the 19 1/2-foot-long, 103-pound giant squid ...

A humpback whale is reflected in Taylor Brooks’ sunglasses as he, his 6-year-old daughter Lily, and his dad, Bill, take part in repainting Whale Walk at Doheny State Beach on Saturday, March 9 ...