Why is the water bear worm called the strongest creature?

Because of its strong vitality, it can survive in the state of freezing, boiling and air drying, even in vacuum or radiation.

Water bears are the most vital creatures known on the earth, and can survive in outer space without protective measures, in the Himalayas (more than 6000 meters, once found at 5546 meters), hot springs, Antarctica and deep sea (less than 4000 meters).

As one of the most vital creatures in the world, the water bear worm can be traced back to Cambrian 500 million years ago. After a long evolution, the water bear worm has become extremely tiny, with eight chubby legs and a water film all over it. Under the microscope, you can see them crawling clumsily forward. Although small, water bear worms can be found everywhere from towering mountains to endless deep seas, from gurgling hot springs to Antarctic ice sheets, and they can lay eggs normally even in a vacuum.

Extended data:

Survival rate of water bear worm:

1, cryptogenic at low temperature

Low temperature will cause low temperature latency. Slow-moving animals can be frozen first and then thawed to recover without causing harm to their bodies. 1975 Crowe put the active Dactylogyrus into 2ml-20℃ water. All experimental animals enter the keg state immediately.

It takes only one minute to thaw in water at 4℃, and 80% of the animals successfully wake up. The priest opened the door and soaked the water bear worm in liquid air at -200℃ for 20 months, in liquid nitrogen at -253℃ for 26 hours and in liquid helium at -272℃ for 8 hours. After the result, the water bear worm "revived" as if nothing had happened.

Some polar fish secrete antifreeze proteins and will not freeze in the body. But the water bear worm seems to allow the body to freeze, or it can repair itself.

2, low humidity hidden

This is the most common form of cryptogenesis, which will happen when the living environment of slow-moving land animals begins to be short of water. But when they touch water again, they can move again in a short time. Including slow-moving animals on land, only they can survive in water. If the surrounding liquid is diluted or even lower than the concentration of body fluids, slow-moving animals will curl up into a ball.

The nail plates on the back will be stacked together, and the elastic cuticle between the nail plates will shrink. Enter the so-called "barrel stage" (t? Nnchenform). In the "small barrel state", their metabolic rate will be reduced to 0.0 1%.

The main reason for entering the keg state is lack of oxygen. When the ventilation is stopped in the experiment, the slow-moving animals will contract. But muscle contraction in water can't last long. Therefore, the "small bucket" will stretch again when it meets water, but the individual will immediately enter a state of suffocation.

The premise that slow-moving animals can survive the water shortage period is that the process is slow and the air humidity cannot be too low. The drying process is too fast for slow-moving animals to shrink. In the experiment aimed at this premise, it can be observed that slow-moving animals are tightly pressed on the surface and it is difficult to recover.

3. Hypoxia and cryptogenesis

Hypoxia occurs when the oxygen content in the liquid around a slow-moving animal is below the threshold. At first, slow-moving animals contract first, but then they will stretch to the maximum, and they are also in a state of suffocation, unable to excrete water from their bodies. Some species can live for five days without oxygen. The metabolic state of slow-moving animals when they are dormant under hypoxia is unknown.

4. Infiltration and cryptogenesis

Variable permeability has not been well observed. Infiltration is caused by the increase of osmotic pressure in the environment. Bufo gargarizans can still move in 0.4% salt solution. In 15% salt solution, it will enter the keg state within 9 seconds. Echinococcus can suffocate in fresh water, but if it is put back into seawater, it will wake up within three days.

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