Extremely cold zone, how do these creatures survive in the Arctic?

Produced by: Science Popularization China

Author: Supercontinent Team

Producer: China Science Expo

The creatures in the Arctic have survived the harsh test of nature. They have not only pushed the survival limit of creatures in cold conditions to a new height with their own perseverance, thus maintaining the ecological balance of the marginal zone, but also benefited mankind.

(Photo source: veer photo gallery)

However, humans are now beginning to view the life world of the Arctic from a completely new perspective. For example, scientists have discovered that forests and grasslands in the Arctic and sub-Arctic regions play a crucial role in controlling the carbon cycle that affects and controls the greenhouse effect on Earth. The entire Arctic ecosystem is an extremely important component of the global ecological balance. If the Arctic is polluted, long-distance migratory birds around the world will suffer; if the Arctic ecology is destroyed, the ecology of the earth will lose balance. Of course, it is us humans who will ultimately bear all the consequences.

Indeed, to survive in the harsh natural conditions of the Arctic, one must have some tricks. So, how do these creatures survive in the Arctic?

Survival skills of insects and plants

Take insects for example, the trials they have endured are enough to make humans feel inferior. Because humans can wear thick cotton clothes to resist the cold, but tiny insects can only be naked forever, so how can they survive the cold winter in the Arctic?

In fact, most insects spend about nine months of the year in a frozen state. They exist in soil, mud or swamps, frozen together with the surrounding materials, and use sleep to resist the unbearable cold. However, we know that ice is a crystal, and if the insects' bodies also crystallize, it is possible to strain or twist their blood vessels, thus destroying their bodies. In order to prevent this, Arctic insects have evolved a survival skill, that is, before entering hibernation, they can automatically reduce the water in their cells to a minimum, thereby effectively avoiding crystallization. In this way, they can sleep soundly throughout the long winter.

In the Arctic, even those seemingly inconspicuous plants have their own survival skills.

Moss on rocks at the bottom of the mountain

(Photo source: CCTV.com photo by Yuan Man)

Snow cover and the permafrost formed by extremely low winter temperatures are very unfavorable for plant growth, but they have developed a special way of life that is adaptable to their natural environment. Lichens can still grow at -20℃, some mosses can still grow at -10℃, and flowering plants such as glacier buttercups and creeping azaleas continue to grow at -5℃. Shrubs almost all form a dwarf form in the shape of a hedge and can use radiation energy for photosynthesis. The synthesized nutrients can enable them to grow in cold and barren land.

In the cold Arctic environment, trees grow extremely slowly, and their trunks are characterized by being curved. For example, the American mountain ash is over 2 meters tall in its native Alaska and Canada, but in Greenland it is like a low shrub, with only a few naked ones reaching 1.5 meters tall, and their trunk diameter does not exceed 1 to 3 centimeters.

In addition, flowering plants in the Arctic can complete their flowering and fruiting life cycle in two months or even one and a half months to make full use of the short summer. Some even flower this year and bear fruit next year. During the long winter, they stop growing.

Arctic Animals' Survival Skills

In the Arctic, even the tiny lemmings have their own tricks: in the cold winter, they survive by digging tunnels. However, it is not easy to dig a network of tunnels in the frozen soil; therefore, every autumn, the front paws of the lemmings will grow a thick layer of cuticle, like two small shovels, so they can dig holes much faster.

(Photo source: veer photo gallery)

Large animals such as foxes, wolves, musk oxen and polar bears rely on their thick fur and constant movement to maintain body temperature and resist the cold. Although polar bears sometimes hibernate, they do not sleep with their heads tucked in. Instead, they keep one eye open and one eye closed, maintaining a high level of vigilance. As long as there is any sign of trouble, they will immediately wake up and be ready to attack at any time.

(Photo source: veer photo gallery)

The mammals living in the Arctic Ocean use unique methods to keep warm. For example, a sea otter has 800 million hairs on its body, and a fur seal has more than 46,000 hairs per square centimeter. Their hair is so dense that even the pervasive seawater cannot penetrate it. These dense hairs are filled with dry and warm air, allowing them to live very comfortably even in the cold seawater.

(Photo source: veer photo gallery)

Large marine mammals such as seals, walruses and whales have a common feature, that is, their bodies are round, like a cannonball, which not only greatly reduces resistance when they swim, but also effectively reduces heat loss. Of course, the reason why they can maintain their body temperature of about 40℃ in the cold sea water is mainly due to the extremely thick skin and the thick layer of fat below the skin. The thickness of subcutaneous fat of different types of whales is different, some are only a few centimeters, and some are half a meter thick, which plays a good role in heat insulation. However, there are pros and cons. When whales swim for a long time or run away desperately when encountering danger, the large amount of heat generated in their bodies is difficult to dissipate. In order to solve this problem, a dense network of blood vessels is distributed below the surface of their skin, which is controlled by nerves and muscles. When they are overheated, a large amount of hot blood will flow into this network to cool down, and the temperature can drop to about 3℃, which is similar to the radiator of a car.

In the long process of evolution, life in the Arctic has learned to adapt to the white environment. However, due to the development of the Arctic and global warming, the reduction of sea ice has had a great impact on the animals and plants living in the Arctic. On this issue, China has always insisted on strengthening Arctic protection and actively promoting Arctic cooperation. We hope that all mankind will jointly respond to the ecological and environmental challenges facing the Arctic and work together to protect life in the Arctic.