Russian biologists have found worms in the Siberian permafrost that have come back to life after 42,000 years.
The scientists collected more than 300 samples from different eras and areas from the frozen ground. Viable roundworms were found in two of them. The animals were placed in a Petri dish at a temperature of 20 degrees. After a while they started crawling around and eating. It is the first evidence that multicells in the Arctic permafrost do cryptobiose. Earlier, worms came back to life after 25 and 39 years respectively. But they could have been frozen for thousands of years.
Due to global warming, the permafrost is thawing. This is worrisome, because in the first place a lot of methane is released that speeds up the heat and secondly because the thaw can bring out all sorts of viruses and bacteria. The ice can contain germs that can come back to life after many thousands of years as the region warms up. For example, a dangerous virus was previously discovered that had been frozen for 30,000 years, but that was still able to infect organisms.