A whale of a mystery: How did they get so big?

A whale of a mystery: How did they get so big?

Pyenson's own work measuring more than 140 fossil specimens of whales, some of which date as far back as 30 million years, showed that for most of their evolutionary history, baleen whales were much smaller than they are today - closer in size to a minivan than a bus or bigger.

"If you watch closely in the second clip you can see the adult blue whale "porpoising" away, swimming at full speed out of the water on the other side of our boat in the upper left hand corner". The first one is that whales simply grew because they could, as water provides a lot of buoyancy for their bodies. Before the ice age, the small crustaceans and microscopic plankton eaten by baleen whales swam throughout all the Earth's oceans. Members of the baleen family of whale, blue whales have a size that feels prehistoric. The baleen filter looks like bristles of a comb and is made up of keratin - the same stuff in our fingernails. It's a highly efficient way to eat, allowing whales to pack on the pounds.

This is the extraordinary finding from a new study that examined the fossil record of baleens - the group of filter feeders to which the blues belong.

A study that will be published tomorrow in the Proceedings of the Royal Society B investigated what could account for the fairly recent evolution of whale gigantism. The researchers think changes in climate led to increased runoff and more nutrients pouring into the coasts. But then there is a transition, in which dense aggregations of nutrients can be found along certain coastlines, while vast parts of the open ocean are virtual marine deserts. With easy excess to food, the whales became so enormous and their foraging behavior got even more efficient as their body size increased.

To put it simply, big whales are better equipped at eating small dense patches of food while the smaller ones must have been better at eating from dispersed areas.

The changes in the ocean also allowed to whales to get really big, really fast. Using a statistical model, they found that several distinct lineages of baleen whales developed independently of one another starting around 4.5 million years ago.

A few million years ago, the largest whales, averaged maybe 15 feet long.

The clip was uploaded to YouTube by Monterey Bay Whale Watch, who wrote: "While watching Emma's family group they suddenly came across a Blue Whale in their path!"

Goldbogen is more than a little excited to be studying these ocean giants.

Friedlaender adds that the paper can also help us understand how climate change might affect these water giants.

It is the largest vertebrate animal that has ever lived. They weigh more than even the biggest dinosaurs. NPR's Madeline Sofia reports.

In a flurry of white water and spume, the blue whale has to take evasive action or face an agonising death in the razor-sharp jaws of the orca.

Co-author from Stanford University in California, Dr Jeremy Goldbogen, said: "We live in a time of giants". The researchers theorize that after temperatures dropped and sheets of ice stretched over the oceans, the whale's tiny prey became isolated and grouped together.

Baleen whales have a filter feeding system (pictured) inside their mouths called a baleen. It allows whales to pack on the pounds. Whales that had teeth instead of baleen, however, did not survive.

'Baleen whales have never been this big, ever'. Goldbogen suggests it was all about the food.

For the unfamiliar, upwelling is the process where high intensity winds may erode the surface water, which results in deeper waters replacing the former. Get to know what climate change has to do with it. But the food was more densely packed.

SOFIA: Some species got 10 times bigger in just a few million years. Unlike no other time in Earth's history.

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