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Are giant Arctic viruses fighting climate change?

In John Carpenter's horror classic from 1982 The matterResearchers at a research station in Antarctica encounter a shape-shifting alien being who was brought back to life after being frozen in the polar ice. Since the film's release, scientists have discovered strikingly similar events in the real world, only on a smaller and less violent scale.

As climate change turns up the global thermostat and glaciers and ice sheets melt, some ancient organisms previously lost in time are resurfacing. Reports of time-hopping plants and microbes have made some scientists and the public concerned that melting ice could be something much thing-like. Now researchers have discovered giant viruses that live on the frost, but it looks like they're on our side!

More information about viruses:
Scientists have recovered a new type of virus from the deepest part of the ocean
First known “vampire virus” clings to the “neck” of other viruses to survive
Melting permafrost could release time-traveling pathogens

Ancient plants, animals and microbes awaken from their deep sleep

Over the past few decades, scientists around the world have discovered all sorts of organisms frozen in ice, which happily wander the earth again once it has thawed. In 2012, scientists announced that they had recovered fruit from the Siberian permafrost that had been buried for more than 30,000 years. They discovered 70 hibernation caves along a river bank, in the same layers of earth where mammoths and other prehistoric animals lived.

The caves were used by prehistoric squirrels as winter quarters, where they also stored the food they had hoarded during the growing season. These squirrels stored their winter supplies in the coldest parts of their caves, which then froze over and never thawed again. When the caves were discovered by scientists, they were still sitting there, waiting for the squirrels to return. After they thawed, the researchers were able to grow new plants from the fruit. Interestingly, they grew the new plants not from ripe seeds, but from the fruit tissue, which was protected from the cold by its sugar content.

In another study, researchers resurrected a nematode (a type of microscopic worm and one of the most successful organisms on the planet) from the late Pleistocene, about 46,000 years ago. It's an exciting time to study biology and evolution, as you can compare ancient organisms with their living modern counterparts, but there are some concerns that melting ice could reawaken something sinister.

Giant viruses slow climate change by infecting ice-darkening algae

A new study appeared in the journal Microbiome suggests that resurrected ice organisms may not be all bad after all. Laura Perini of the Institute of Environmental Sciences at Aarhus University and her colleagues traveled to Greenland and found (relatively speaking) giant viruses living on the ice that may help mitigate climate change.

Researchers collected ice and snow samples from across the ice sheet and then analyzed those samples for DNA to determine what microscopic creatures might be living on or in them. They found DNA from a group of large viruses called nucleocytoplasmic large DNA viruses (DCLDV), which are known to infect eukaryotic organisms.

DCLDV DNA appeared in various types of snow and ice, but was most abundant in snow where algae lived. To be sure, the researchers then looked for active mRNA, which is created when parts of the genome are transcribed. Finding mRNA meant that the DNA came from active viruses, not ones that had been frozen for long periods.

“We don't know much about the viruses, but I think they could be useful in slowing down the melting of ice caused by algal blooms. How specific they are and how efficient they would be, we don't yet know. But through further investigation, we hope to answer some of these questions,” Perini said in a statement.

Every spring, as temperatures rise and the ice begins to melt, algae that live on the ice surface bloom, covering the ice with dark-colored streaks. As they grow, they turn black, turning the ice sheet into an asphalt that reflects sunlight less well. This makes the ice warmer and the melting process speeds up. But as temperatures rise, these giant viruses also wake up and start looking for algae to infect. These viruses, while still microscopic, are larger than most bacteria and more than 100 times larger than ordinary viruses.

These tiny algae hunters could be a kind of top-down ecosystem control, preventing algae populations on the ice from getting out of control. For every algal bloom like this one, there's a viral RJ MacReady waiting to fight it.

Watch The Thing from Another World, directed by John Carpenter, available from Universal Pictures.