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The living beings, not even a millimeter in size, are hard-boiled.

When life is not going well with them, tardigrades shut down their body processes and contract.

They replace the water in their cells with proteins.

In this dry state, extreme temperatures, high pressure, drought and even the vacuum of space cannot harm them.

Only when the circumstances around them are life-friendly again do the animals wake up - even if this is the case only after decades.

Scientists from the Indian Institute of Science have found a new type of vacuum cleaner bag on eight legs that has another resistance:

These tardigrade can withstand high doses of UV radiation that would be fatal to other living things.

Source: Getty Images / Science Photo Libra / SEBASTIAN KAULITZKI / SCIENCE PHOTO LIBRARY

The biochemists discovered the new species by chance in a moss sample from a concrete wall on campus when they were looking for the tiny creatures.

Tardigrade can be found all over the world.

The main thing: it's wet there.

Because the animals have to be permanently covered by a film of water.

Hence they are also called water bears.

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Back in the laboratory, the researchers irradiated them with intense UV light, which is normally used for disinfection. It breaks down the chemical compounds in a cell, which as a rule no living being can survive. Bacteria and worms that were also tested withstood a dose of one kilojoule of ultraviolet energy per square meter for only about five minutes. Tardigrade of the well-known species

Hypsibius exemplaris

survived at least 24 hours. But brown-colored specimens of a previously unknown species survived even four times the dose of UV radiation for 30 days, as the scientists write in their study in the journal "Biology Letters".

Another amazing discovery: these

Paramacrobiotus

water bears

glowed blue under the ultraviolet light.

Source: Harikumar Suma, Sandeep Eswarappa, Indian Institute of Science, Biology Letters 2020

Apparently the fluorescence protected against UV radiation.

To prove this, the researchers produced an extract from the fluorescent dyes and used it to treat the more UV-sensitive tardigrade of the species

Hypsibius exemplaris.

In fact, these survived radiation twice as long as before.

So the fluorescence really offered some protection.

The scientists suspect that the tardigrade developed this "super power" to survive the high levels of UV light on the sunny summer days in India.

This article was first published in October 2020.