A Giant Fossil Discovery

Researchers have uncovered fossil remains from what is believed to be the heaviest animal known to have existed, according to findings published yesterday. The specimen is an ancient whale species—dubbed Perucetus colossus, or "the colossal whale from Peru"—roughly 39 million years old.

The creature is estimated to have weighed more than 300 tons or more, two to three times the size of a blue whale (the current record holder). Estimates were modeled from a partial skeleton, which included individual vertebrae weighing more than 220 pounds each—only one to two has been excavated each year since the site was discovered a decade ago.

Cetaceans have long fascinated evolutionary scientists. Their ancestors emerged from the ocean onto land roughly 400 million years ago but returned to the sea 50 million years later. Scientists say the discovery challenges conventional theory on how big mammals can grow.

Read the abstract from the paper detailing the discovery here.