Nature & Environment

How Did Whales Get So Big?

Brooke James
First Posted: May 24, 2017 05:40 AM EDT

Scientists say that there is so much about the oceans that humans are yet to discover. What they do know only led to more questions and few have answers. Then there are whales -- massive, mysterious creatures -- that turned out to be less massive than how people know them now.

According to a recent study, it seems that a few million years ago, the largest whales averaged at about 15 feet long. They are not minuscule but they are not gargantuan either. Seemingly overnight, though, toothless baleen whales grew larger.

Today, a blue whale could go as long as 100 feet -- and considered to be the largest creature ever to have been on Earth. The skulls of this kind of whales alone are bigger than mini vans and could fit more than five people inside.

Lead author Graham Slater noted that whales seem to have changed "in the blink of an evolutionary eye." It seems that this change occurred during the ice ages, thanks to the change in the oceans and whale food supplies.

With the help of fossil records, scientists were able to create a family tree for baleen whales. The Washington Post noted that the list today includes massive species such as blue whales, humpback whales and right whales. Computer simulations and knowledge on evolution led the scientists to believe that smaller species became extinct somewhere around a few hundred thousand years ago to 4.5 million years ago.

The study, published in the Proceedings of the Royal Society B, noted that the size of whales started changing as the poles got colder and the ice expanded. At the point, cold water went deeper and moved closer to the equator. The whales then became exposed to a lot of food most of the time -- like a person going to eat-all-you-can buffets every day instead of buying single-serving-sized food.

"If you are a whale, the easiest way to take advantage of dense but sparsely available resources is to get big. If you are big, you basically can get more miles to the gallon," Slater shared.

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