Ancient Worms Revived After 46,000 Years Frozen in Siberian Permafrost
By: Kyle Xu
46,000 years ago, at a time when the high and mighty woolly mammoths reigned as the ancient superiors of the Earth, an insignificant, minuscule pair of roundworms became frozen like statues, encased in the Siberian permafrost.
Now, millennia later, these tiny roundworms, thawed from their prison of ice, continue to once again live, squirming and wriggling as they demonstrate to our scientists that life can be halted.
This new discovery was published in the PLOS Genetics journal. How can these worms, also known as nematodes, whose lives are measured in days, possibly survive in the most bizarre and extreme conditions for tens of thousands of years?
The answer lies in a dormant state named cryptobiosis, which the millimeter-long worms used to survive the extreme temperatures.
Cryptobiosis is known as a physiological state in which metabolic activity is reduced to an undetectable level without disappearing altogether, a special dormant state found in certain groups of plants and animals.
These roundworms survived 40 meters below the surface in the Siberian permafrost in the cryptobiotic state, according to Teymuras Kurzchalia, a professor at the Max Planck Institute of Molecular Cell Biology and Genetics in Dresden and one of the scientists involved in the research.
“The major take-home message or summary of this discovery is that it is, in principle, possible to stop life for more or less an indefinite time and then restart it,” stated Dr. Kurzchalia.
Researchers started to research the genes in the nematode that allow it to enter the cryptobiotic state. Those very genes were also found in a nematode called Caenorhabditis elegans, suggesting that they can also achieve cryptobiosis.
“This led us, for instance, to understand that they cannot survive without a specific sugar called trehalose,” Dr. Kurzchalia said. “Without this sugar, they just die.”
While cryptobiosis still remains a mystery, it should not stop the thirst for research, explained Kurzchalia.
Just like the discovery of semiconductors, or of the DNA structure, this breakthrough may ultimately turn out to be revolutionary, he said.
Perhaps one day, cryptobiosis could be engineered by humans.