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Scientists recently awakened ancient microbes that had been trapped in ice, some for around 40,000 years. The ancient life was discovered in the U.S. Army Corps of Engineers’ Permafrost Tunnel near Fairbanks, Alaska.
According to a statement by the team of geologists and biologists from the University of Colorado-Boulder, they “discovered that if you thaw out permafrost, the microbes within will take a while to become active.” They added that “after a few months, like waking up after a long nap, they begin to form flourishing colonies.”
Their findings were published in the journal JGR Biogeosciences. In that report, the researchers noted that permafrost, a frozen mix of soil, ice and rocks, is at risk of thawing as cold regions in the Northern Hemisphere continue to warm. As it does, microorganisms may resuscitate and proliferate, some which have been isolated for hundreds, thousands, or even millions of years.
“These are not dead samples by any means,” said Tristan Caro, lead author of the study and a postdoctoral researcher at the California Institute of Technology. “They’re still very much capable of hosting robust life that can break down organic matter and release it as carbon dioxide.”
This is an area of concern to the researchers because, as they put it, “as permafrost thaws, microbes living in the soil will begin to break down organic matter, spewing it into the air as carbon dioxide and methane — both potent greenhouse gases.”
What the scientists found in the Permafrost Tunnel was ‘very exciting’
Deep within the U.S. Army Corps of Engineers’ Permafrost Tunnel, which goes more than 350 feet into the frozen ground beneath central Alaska, bones of ancient bison and mammoth could be seen sticking out from the walls.
“The first thing you notice when you walk in there is that it smells really bad. It smells like a musty basement that’s been left to sit for way too long,” said Caro. “To a microbiologist, that’s very exciting because interesting smells are often microbial.”
The scientists took samples from the tunnel and then simulated “what happens in an Alaskan summer, under future climate conditions where these temperatures reach deeper areas of the permafrost.” After six months of exposure to water and temperatures of between 39 and 54 degrees Fahrenheit, some bacterial colonies produced membranes made of fatty material, gooey structures called “biofilms,” that surround all living cells.
“Microbial communities that survive and proliferate after burial for thousands of years do not resemble those on the surface and exhibit reduced diversity,” the researchers wrote in their report. “Finally, we note that microbes in subsurface permafrost rely on different kinds of lipids to construct their cell membranes: these compounds may have helped them survive freezing, dark conditions for millenia.”
Caro said that while these microbes likely can’t infect people, the research team still kept them in sealed chambers, just in case.