Whales are considered one of the largest animals.on our planet, because their body length is usually about 25 meters, and their mass reaches 90 tons. Despite the fact that these mammals have been known to people since very ancient times and are even mentioned in myths and legends, scientists still do not know much about them. For example, only recently, researchers from the US state of Hawaii were able to film how the whales hunt huge schools of fish in a cunning way. However, scientists were also very interested in why these huge creatures swim each year from cold to warm waters overcoming more than 20 thousand kilometers. Such migration requires a lot of effort, but it turned out that mammals just need to overcome such distances in order to change their skin and not die from diseases.
About the new discovery of scientists from the American stateOregon was told in the scientific journal Marine Mammal Science. Previously, scientists believed that in the cold waters of the Arctic and Antarctic whales only hunt and gain strength, and for breeding and nursing offspring swim in the warm regions of our planet. However, while observing 60 whales using GPS sensors, scientists noticed that some individuals cross tens of thousands of kilometers in a month. Moreover, much more calves were found in the colder regions of our planet than in the warmer ones. And this means that they swim to warmer climes not for breeding, but for a completely different reason.
Why do whales migrate to warmer climes?
According to study leader RobertPitman, whales swim to warm edges in order to change old skin to new. At least this is evidenced by traces of discarded old skin in the warm waters of our planet. The assumption seems very realistic, because the process of skin change in whales is started only in a warm environment, and in cold waters it stops. It is known that in the Arctic and Antarctic, old whale skin forms layers of algae, which are breeding grounds for harmful bacteria.
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Scientists believe that slowing down the shift processThe skin of whales is due to the fact that in cold water their vessels are narrowed to maintain body heat. Along with the slowdown of blood circulation, the process of restoration of the skin is slowed down. Perhaps the whales swim in warm waters precisely because they need to expand the vessels and allow the body to lose its old cover with pathogenic bacteria. This assumption seems to be closer to the truth than the theory that whales swim thousands of kilometers for breeding.
In general, scientists are not only puzzled by the mysteriouswhale migration. It is also not clear to them why some species of aquatic inhabitants gather in certain places. For example, for many years scientists have noticed that white sharks annually gather in the same place off the coast of Australia. It could be assumed that predators simply want to feast on the seals living in these parts. Only for some reason they gather at this place even in the summer, when there is practically no food for them there. You can read more about the mysterious movement of white sharks in our special material.