“More questions than answers,” say scientists uncertain about the biological mechanisms of some organisms found in permafrost siberiano. This is an “evolutionary scandal”, as they were previously called by the biologists involved in the study, as these microscopic, worm-like creatures have been able to thrive for millions of years without ever actually performing the act of reproduction.
However, what is particularly surprising about these organisms is that they have been able to survive in the perennially frozen soil of Siberia for over 24 thousand years, an age demonstrated by radiocarbon dating, and, furthermore, that once thawed they have proliferated.
The name of these small organisms is rotiferi bdelloidei, are exclusively female multicellular invertebrates. They are then equipped with a complete digestive system that includes both mouth and anus. Already known by science for their incredible ability to resist radiation and absolutely inhospitable environments. What allows them to resist in any condition is the ability they have to stop all activities and block their metabolism. 24 thousand years in the Siberian permafrost amply demonstrate this. They have been present on Earth for at least 35 million years and today it is easy to find them in lakes, ponds, streams or in any case very humid habitats such as mosses and lichens.
They therefore enter a “state between life and death” called cryptobiosi, explains al Guardian Stas Malavin, researcher at the Soil Cryology Laboratory in Pushchino, Russia. A news that for scholars of the subject was shocking since it was shown that the creatures could survive frozen for up to about 10 years. These rotifers have spent their existence, according to studies, under the legs of woolly creatures such as the now extinct woolly rhinoceros. Despite carbon dating, however, scholars remain doubtful about the actual ability of these organisms to survive frozen for so long. In the same way, however, they represent an excellent opportunity to find ways to improve the cryopreservation of cells, tissues and organs.
“Human beings cannot preserve organs and tissues for such a considerable time” – explains Malavin – “These rotifers, together with other organisms found in the permafrost, represent the result of a great natural experiment that we cannot replicate … but they are good models to be studied further “.
Furthermore, explains Matthew Cobb, professor of zoology at the University of Manchester, that there are many organisms frozen in the permafrost that with the global warming they could come back to life. “This doesn’t mean that terrifying things will come out and eat us, but it does give scientists a chance to study.” – Cobb clarifies – “how the rotifer has adapted to resist the bad effects of freezing and the opportunity to explore the difference between existing species and their predecessors”.
Other microorganisms were also found in the permafrost and immediately isolated by the Soil Cryology Lab, including a nematode worm dating back 30,000 years.