Polar bears are the largest land carnivores, living in the cold near the Arctic Circle and feeding on fatty marine fish and seals. Not only do adult polar bears eat a high-fat diet, but the breast milk that polar bear cubs drink is also "high-fat milk" - the fat content of milk is generally 3%, but the fat content of polar bear milk is as high
That's 10 times more than cow's milk.
If you eat greasy, of course, you will grow fat.
When we describe a person as fat and thin, we often say "thin like a monkey" and "fat like a pig", and the body fat percentage of chimpanzees is 36%, is a well-deserved thin man, the body fat rate of domestic pigs is 15%, human because of adequate nutrition, body fat rate of 8% 35%, many people's body fat rate is more than domestic pigs.
Human body fat percentage reference.
WhileThe body fat percentage of polar bears is generally around 50%.It is several times more than that of domestic pigs, truly "fatter than a pig".
For polar bears, such a body fat percentage isNormalTarget.
The Arctic Circle is a harsh environment, and even high-fighting polar bears cannot catch food every day, especially in winter, when it is possible to go months without food. The thick fat of polar bears is their magic weapon to prevent starvation from dying during the months of starvation. Moreover, polar bears, unlike other animals, never have to worry about the "three highs" caused by obesity and cardiovascular diseases. (so envious).
In 2014, scientists analyzed the genomes of 79 polar bears and 10 brown bears from Sweden, Finland and Alaska and found that several genes related to fat transport and fatty acid metabolism in polar bears were mutatedNo matter how much high-fat food they eat and how fat they get, they are still healthy。(The real-name system is envious).
In mammalian fat metabolism, there is an important gene called apolipoprotein B gene (APOB), which synthesizes apolipoprotein B is the main protein in low-density lipoprotein (LDL), and the low-density cholesterol it binds is harmful to the body, which can cause hyperlipidemia and cardiovascular diseases. Unlike other animals, polar bears have mutated in the APOB gene, which lowers blood cholesterol. This is the first time that genes have been found in polar bears that can prevent hyperlipidemia and cardiovascular disease.
Because modern people are too well nourished, "three highs" and cardiovascular diseases are not uncommon. These fat metabolism-related genes of polar bears may provide new directions and ideas for the prevention of cardiovascular diseases caused by hyperlipidemia in humans.
The study also found that polar bears and temperate brown bears actually descended from the same ancestor, and they were born at 3430,000 47They parted ways 90,000 years ago, and modern humans "separated" from Neanderthals about 500,000 years ago, which means that polar bears and brown bears evolved at about the same distance as modern humans and Neanderthals.
Hundreds of thousands of years ago, there was a period of warm climate on Earth, and the Arctic Circle was not as cold as it is today, so some brown bears (ursus arctos) living in temperate zones migrated to the Arctic Circle. Later, during the cold period, these brown bears living in the Arctic Circle were forced to undergo a series of evolutions in order to adapt to the cold environment, and eventually became today's polar bears. The fact that a large mammal can complete such a large change in a very short period of time is indeed an extremely rare evolutionary event and has important research value.
In addition to being able to adapt to a high-fat diet,Polar bears have also evolved many characteristics that are different from brown bears。For example, the polar bear's genes that control the color of its fur have been altered, making it crystal clear and almost transparent, and the hair will appear white when it reflects natural light, which is an excellent protective color in the snow and ice. In addition, there is no grass on the ice, and if you want to forage for food, you have to go into the sea to hunt fish and seals, so polar bears have also evolved a streamlined body shape, which can reduce resistance and swim faster when swimming in water.
Although polar bears are very different from brown bears in appearance and physiology, they are indeed genetically close relatives, and polar bears and brown bears have even crossed many times to give birth to offspring, which shows that they are closely related and there is no interspecific isolation.
As the global climate warms, some brown bears are setting foot in the Arctic Circle again.
Since 2006, the Arctic Circle has seen a number of polar bears with a larger head and brown paws. This is the offspring of a cross between a brown bear and a polar bear.
*: Sea World Culture is unlimited.
Marine environmental forecast for the next two days
Expected tomorrow,
The Bohai Sea has 1 to 15 meters of light to medium waves;
In the northern part of the Yellow Sea there are 16 to 23 meters in the middle wave area;
There are 2 in the southern part of the Yellow Sea and the northern part of the East China Sea5 to 37 meters of big wave area;
There are 3 in the southern part of the East China Sea and the waters near the Diaoyu Islands4 to 42 meters of big waves to big wave area;
There are 3 in the Taiwan Strait7 to 41 meter big wave to big wave area;
There are 32 to 36 meters of large wave area;
There are 2 in the Bass Strait9 to 38 meters of large wave area;
There are 3 to 3 in the northern part of the South China Sea7 meters of big wave area;
There are 2 to 2 in the central part of the South China Sea9 meters of medium to large waves;
In the southern part of the South China Sea there are 18 to 25 meters of medium to large waves;
There are 2 to 2 in the Gulf of Tonkin5 meters of medium to large waves;
It is expected the day after tomorrow,
The southern Yellow Sea and the northern part of the East China Sea are maintained in large waves, with a wave height of 18 to 28 meters;
The southern part of the East China Sea and the waters near the Diaoyu Islands maintained a high wave height of 24 to 38 meters;
The large wave area of the Taiwan Strait is maintained, and the wave height is 27 to 39 meters;
The large wave area east of Taiwan is maintained, and the wave height is 28 to 36 meters;
The large wave area of the Bass Strait is maintained, and the wave height is 28 to 36 meters;
The large wave area in the northern part of the South China Sea is maintained, with a wave height of 3 to 37 meters;
The large wave area in the central part of the South China Sea is maintained, and the wave height is 26 to 32 meters;
The large wave area in the southern part of the South China Sea is maintained, with a wave height of 2 to 25 meters;
The large wave area of the Beibu Gulf weakened and disappeared
Numerical prediction of waves in the Northwest Pacific Ocean on February 29 and March 4.
Beautiful sea conditions in the waters of the island
Expected tomorrow,
There are 3 in the waters near the Diaoyu Islands8 meters of big waves,There are 3 in the sea near Pingtan Island3 meters of big waves,There are 25~2.9 meters of big waves,There are 2 in the waters near Dachen Island, Dongtou Island, Yuanshan Island and Fiery Cross Reef1~2.4m of the middle wave,Take the sea islandNot suitable for travel by boat;
There are 18~2m of the middle wave,Truong Son Islands,Liugong Island, Chongming Island, Daishan Island, Putuo Mountain, Yuhuan Island, Sandu Island, Chuanshan Islands, Hailing Island, Nansan Island, Donghai Island, Weizhou Island, Huangyan Island near the sea area has 13~1.7m of the middle wave,These islands are more suitable for boat tripsplay with the island;
The waters near other beautiful islands in our country are light waves, and the sea conditions are good, which is very suitable for boat trips and island tours.
Beautiful islands are the following 35 islands:
Juehua Island, Changshan Islands, Bodhi Island, Changdao, Liugong Island, Lingshan Island, Qinshan Island, Liandao, Chongming Island, Shengsi Islands, Daishan Island, Dongji Island, Putuo Mountain, Dachen Island, Yuhuan Island, Dongtou Island, Nanji Island, Yuanshan Island, Sandu Island, Pingtan Island, Meizhou Island, Dongshan Island, Diaoyu Island, Nanao Island, Wanshan Islands, Chuanshan Islands, Hailing Island, Nansan Island, Donghai Island, Weizhou Island, Boundary Island Island, Wuzhizhou Island, Yongxing Island, Huangyan Island, Fiery Cross Reef.
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