How to live in the coldest place on Earth

In order to survive in Antarctica, species must have evolved to change their biochemical and shape properties.

How the species survive in Antarctica

According to the BBC, about 80% of the Earth's biosphere always has a temperature below 5 degrees Celsius. This means that the system of cold-tolerant organisms is rich, varied and widely distributed than any other life form.

Emperor penguins dive underwater.(Photo: Doug Allan / NPL)

In the Antarctica continent , 400 miles west of Antarctica, Lake Whillans is the coldest place on Earth. In 2013, scientists drilled through the ice above the surface of the lake and discovered unicellular protozoa that flourished in conditions of total lightlessness, by taking energy from the rocks. below the ice. This is a typical example of life in harsh cold conditions.

In Antarctica , plants and animals and bacteria face many challenges. Warm-blooded animals must consume a lot of energy to maintain body temperature, meaning they need a large source of food. However, due to the lack of sunlight, the flora and the first base of all food chains here are very poor. Meanwhile, cold-blooded animals must utilize the meager heat from the Sun to maintain body reactions, and must deal with serious risks due to low temperatures.

In response to these challenges, animals evolved in a number of ways to keep warm. For example, warm-blooded animals, their bodies are huge.Seals and penguins all have a large body volume, but the skin surface area is small to limit heat loss through the skin. Penguins also reduce the surface area of ​​skin exposed to the air by shrinking into small groups.

Emperor penguins, whales and seals , species that live both underwater and on land have an extra layer of special fat under their skin, which has a very good insulation effect. Although the sea water here always has temperatures ranging from -2 to 2 degrees Celsius with a thermal conductivity 25 times higher than air, they still maintain their body temperature at 35-42 degrees Celsius.

Some fish evolve vascular systems deep in the body to prevent heat loss, or have anti-freezing agents in the blood. These are protein molecules attached to sugar molecules, which effectively isolate any ice crystals that form in the blood or tissue, before sharp edges of the ice puncture the cell membrane.

Mollusc crustaceans, a basic food source in Antarctica.(Photo: David Tipling / NPL)

For deep-lived fish, their bodies are not frozen even though the temperature of the surrounding water is much lower than the freezing point of the body. However, if these fish are brought up, near the water surface, ice crystals will form, causing their bodies to freeze.

In addition, most of the creatures here eat meat - how to effectively extract energy against the cold. This food source is provided by the ocean. In the summer, the sun shines 24 hours, the phytoplankton can continuously photosynthesize. They are food for small mollusc crustaceans. Finally, these mollusc animals are food for many Antarctic animals. In the summer, a blue whale can eat up to 6 tons of mollusk a day.

Some terrestrial creatures also find ways to adapt to climate conditions, such as the wingless insect Belgica antarctica living on the rocky outcrops of the Antarctica peninsula.

Most of the time in its 2-year life cycle lives in the form of larvae in the ice, only rising to the surface in the summer months 12 and 1 warm, and ready to enter a sleep state if the temperature falls. It has no wings so the wind cannot blow. Small size of only 13 mm makes it easy to warm the body. It is also the insect with the shortest genome, with only 99 million encoded DNA, compared with 3.2 billion for humans, and very few repeating sequences, which is also a way to help it survive. In addition, they also have special genes against cell-destroying chemicals and DNA, collectively known as ROS . These are substances produced by cells due to extreme conditions such as low temperature, aridity and radiation.

In the Antarctic valleys , the coldest and driest places on Earth, only bacteria survive. The cell membrane of the bacteria here has a high concentration of unsaturated fatty acids to keep the liquid at low temperatures. They also create many proteins and enzymes that can work in low temperature conditions, protect DNA, and also activate genes against ROS. Some species of bacteria are also capable of producing special molecules, like fish, to counteract cell freezing and form ice crystals. Some other species make their own air bags that protect their bodies from cold and move to warmer places, or simply live in areas with high concentrations of salt to prevent them from freezing. When the temperature drops too low, some species go into hibernation, all activities stop.

A species of bacteria at Antarctic lake.(Photo: Penn State University / SPL)

As the Earth heats up today, a few bacteria in Antarctica will grow more smoothly, but for most other organisms this is bad news. Some will have to move to deeper layers, where temperatures are relatively stable, while others will enter a long hibernation state, waiting for the new ice age. The number of emperor penguins will decline by about 19% by 2100, according to a 2014 study.