New Microbes Found in Antarctica

[Hashi Lebwohl]

Here is the article I found via the weekly Mensa newsletter. The article contains a link to the source article published in Nature.

Biologists have extracted mineral-eating microbes from a lake buried a half mile below the surface of the West Antarctic Ice Sheet, according to a new study published in Nature.

Earlier claims of similar microbes drawn from a different Antarctic lake, say the study's authors, were controversial because the samples had been contaminated—a problem eliminated in this case by especially careful drilling techniques.

"The report is a landmark for the polar sciences," writes Martyn Tranter, a geochemist at the University of Bristol, England, who was not involved in the study, in a commentary also published in Nature.

It's also a landmark in the science of astrobiology, the search for life on other worlds. In recent years, scientists have come to understand that life can thrive in a much wider range of environments than they once believed, including superheated water at the bottom of the ocean and ice caves in Greenland. That suggests that extraterrestrial life might also exist in places once thought uninhabitable.

This new identification of microbes in subglacial Lake Whillans, a 6-foot-deep, 20-square-mile (1.8 meters, 52 square kilometers) body of water kept liquid by heat from the bedrock below and friction from glaciers moving over that bedrock, just adds to the possibilities. The authors' findings, Tranter writes, "beg the question of whether microbes could eat rock beneath ice sheets on extraterrestrial bodies such as Mars."

The Lake Whillans microbes, which come from nearly 4,000 distinct species or "operational taxonomic units" (groups of species with similar characteristics), are chemoautotrophs, meaning they get their energy not from sunlight nor from other organisms that live on sunlight, but rather from minerals dissolved in the water, including nitrites, iron, and sulfur compounds.

Given their ability to exist without light or access to organic food sources, the microbes could also be a model for life on Jupiter's ice-covered moon Europa or Saturn's Enceladus. (See "The Hunt for Life Beyond Earth.")

That last bit is the important part--these microbes need neither sunlight nor other organisms for food, only the minerals in the water. This finding increases the probability that similar microbes definitely exist in extraplanetary environments, we simply haven't found them yet.

[Cord Hurn]

It's also a landmark in the science of astrobiology, the search for life on other worlds. In recent years, scientists have come to understand that life can thrive in a much wider range of environments than they once believed, including superheated water at the bottom of the ocean and ice caves in Greenland. That suggests that extraterrestrial life might also exist in places once thought uninhabitable.

Fascinating, Hashi! It gets me to realize that it's appearing far more likely we're not the only life-holding planet in the galaxy, let alone the universe. A literally groundbreaking discovery!

[Vraith]

It's about time! I've seen previous announcements like this that always ended up with questions of contamination and such. Finally it is for sure.

And the last bit is important...especially when combined with the other recent discoveries of critters living in extreme conditions [deep bedrock, underwater volcanic stacks, etc. etc.]