Scientists have made an unexpected statement about whales

2017-10-12 13:35

Scientists have made an unexpected statement about whales
The researchers were able to understand why whales are so large.

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No, I’m not going to tell you that baleen whales are very large. You already know that. And that is the blue whale weighing in at 130 – 200 tons is the heaviest creature on the planet. But I’ll bet that you don’t know why these whales, which feed through a filter that big. Because even scientists don’t know it.

Anyway did not know until today. A group of scientists has proposed an interesting theory in the Works of the Royal society B: reducing the fossil record and phylogenetic work (that is, determining the relationship of species to each other), they found that baleen whales probably have become a giant in just 3 million years ago – a trifle in the great scheme of evolution and this transformation was probably caused by climate change. This, of course, makes us think about what problems may face giant animals as the heating and acidification of the oceans of the Earth, informs Rus.Media with reference to Health.

Baleen whales which swallow huge amounts of water and filter tiny animals like krill, there are about 30 million years. During most of this time they were modestly folded, remaining 10 meters long or so, that is three times less than the modern blue whale. In the end, to be a little convenient. At least easier to open the jaws when it is small.

At the beginning of the ice age about 3 million years ago the oceanic system began to change on a large scale. Ice sheets expanded to the North, and flows have sucked the nutrients out to sea. The increase of wind to upwelling (upwelling of deep waters to the surface) brought even more nutrients from the depths: when the wind blows off the upper layers of water in a deep aspire to replace them. This has led to the flourishing of the plant phytoplankton, which in turn accelerated the reproduction of zooplankton – krill – who eats first. The food of the whales began to gather in certain places at certain times of the year.

The large size would be an advantage for whales in the midst of this climate of transformation due to several factors (this trait evolved independently in different pedigrees of baleen whales, confirming the advantage of the development). First, large whales has changed with the food chain, growing to such proportions that put himself out of reach of predators. Big mouth also more efficiently captured zooplankton. If you can accumulate more fat, you can continue to migrate, in contrast to the small whales that were hanging out in the surrounding waters with low concentrations of plankton.

“We believe that it is an environmental explanation for the change in the size of the body,” says paleobiology and study co-author Nick Penson from the Smithsonian University. “Explains not only the origin of the very large, but also the disappearance of very small baleen whales, which are now represented in this pedigree, only a whale-pygmy.” Smaller whales simply could not compete in the new world order, but what could a whale-pygmy is a mystery.

But couldn’t the whales become great just because you could? Because swimming in water is not something to go with a great body on the ground. “When you study the data, it is excluded,” says Penson. “When the whale hits the water and becomes very large — that’s not so.” In the end, baleen whales lived in water millions of years before becoming a giant.

But the study shows for sure is the exceptionality of this moment natural history of the Earth. Just imagine having to support not only blue whales, but other baleen whales, like gray. They eat while traveling thousands and thousands of nautical miles.

“In history there was still time, when such large predators would find as much fertile biomass in the oceans,” says vertebrate paleontologist Erich Fitzgerald, who was not involved in the study. “Unique in the history just yet. Can be traced back to the end of the era of the dinosaurs, 66 million years ago, and only the last 3 million years will be truly unique.”

People can to ruin it. Small changes in the temperature of the oceans can have a cascading effect on the ecosystem. If currents change or upwelling cold water will stop the output of nutrients to the surface, phytoplankton don’t bloom and the zooplankton will eat. If there is no zooplankton, baleen whales have nothing to eat. If the bloom will move into other areas of the sea and the whales will not be able to find, their advantage in size suddenly becomes a burden.

Climate change has created giants, and although it is too early to say how it will affect them in the coming decades, the giants are certainly in a dangerous situation. Large creatures are at the cutting edge of evolution, by definition. So, science has discovered that large whales were due to climate change. Now we have to ensure that further climate change won’t hurt them.