The permafrost of Siberia is well-known for its ability to preserve biological material that gets trapped under the ice.
In 2016, a Siberian boy died after being exposed to anthrax. It is believed that the boy fell ill after melting permafrost resulted in a well-preserved reindeer’s remains leaking anthrax it had been infected with 75 years ago into the groundwater.
The frozen top layer of soil on the ground in Siberia can contain secrets beyond just infected reindeer, though. Scientists in Siberia have revived an ancient microscopic organism that was trapped under the permafrost for 24,000 years. The animal, a Bdelloid rotifer, is of a species that is renowned for its ability to survive in extreme environments.
The Bdelloid rotifer was found in a sample of soil taken from a drilling apparatus. The animal is very simple compared to something bigger, like a mammal, but it is complicated enough that it has organs and can be described as an animal, not a protist or similar multi-celled microscopic life form. The scientists studying the animal noted that the revival of this specimen is groundbreaking because it shows that animals can be frozen for thousands of years and still be brought back to life later.
The group, working for the Soil Cryology Laboratory at the Pushchino Scientific Center for Biological Research in Russia, has stated that this is a major discovery for science.
Research done by the group indicates that rotifers are somehow able to survive extremely low temperatures in a way that larger life forms aren’t. In mammals, for instance, being frozen is almost always deadly. The ice crystals that form when a mammal is subjected to freezing temperatures can cause organ damage and can destroy blood vessels.
Rotifers, meanwhile, seem to have some form of internal protection that shields them against this type of crystal damage. The scientists tested out freezing modern-day rotifers and found that individuals could sometimes survive the experience if they were frozen slowly. Not every rotifer they froze was able to revive, though, indicating that it’s an inexact process.
Stas Malavin, one of the researchers with the Soil Cryology Lab, pointed out to reporters that this is massive news for biologists and a “dream” of science fiction writers.
“Of course, the more complex the organism, the trickier it is to preserve it alive frozen and, for mammals, it’s not currently possible,” Malavin told reporters. “Yet, moving from a single-celled organism to an organism with a gut and brain, though microscopic, is a big step forward.”