In Depth: How 60,000-Year-Old Ancient Microbes May Hold Clues To History Of Evolution
Microorganisms believed to be 60,000 year old, which were recently discovered by NASA scientists, may hold more clues than meet the eye. Scientists believe the discovery may hold the key to understanding microbial evolutionary history.
Trapped in giant crystals, the microbes thrived in a hostile environment with sulfite, manganese, and copper oxide as their food.
The NASA scientists discovered the ancient bacteria deep into the Naica mountain caves in the Northern Mexican state of Chihuahua.
Ancient Bacteria Hold The Key To Evolutionary History
These microbes may have evolved in order to survive, said Penelope Boston of NASA's Astrobiology Institute at the conference of the American Association for the Advancement of Science over the weekend.
Boston revealed that around 100 kinds of microorganisms have been discovered inside the mine crystals, most of them are bacteria with varying periods from 10,000 to 60,000 years.
Most of these microbes have not been observed before.
The discovery may have "profound effects on how we try to understand the evolutionary history of microbial life on this planet," Boston said.
Bacteria are known to pass their genes even with species different from their own in a process called lateral gene transfer. Ancient bacteria, such as the ones recently discovered, can be used to study the evolution history of microbes.
Extraterrestrial Organisms Can Hitch A Ride To Earth
The condition in Naica is hot, with temperatures ranging from 40-60 degree Celcius — it is also humid and acidic. In the absence of light in its environment, the microbes had to generate energy by processing the rock minerals around them.
These mineral-eating microbes have survived the worst of conditions for thousands of years and it raises a possibility that dangerous microorganisms from space can enter Earth through a returning spaceship and yet survive, NASA scientists warned.
On the other hand, Earth organisms can also potentially contaminate other planets during space missions to Mars or the moon.
There is no way of knowing "true Mars life or life from icy worlds rather than our own," Boston, the new director of NASA's Astrobiology Institute in California, observed.
Not Just Another Contaminant
There were concerns that the newfound microorganisms could be just products of contamination, either introduced by the team of scientists or the mining operations.
Boston admitted this could be possible but at the same time confident that all protocols during the course of the research were followed.
Her confidence is not unfounded.
The Naica caves ooze with diverse life present in the environment, which only meant that "these are fully fledged microbial communities that have their viral load" inherent to any other community.
"So, that's another aspect of this that argues against casual contamination," she said.
As an astrobiologist, Boston believes the Naica caves discovery is relevant in the search for extraterrestrial life.
The discovery is an added collection to the "atlas of possibilities that we can apply to different planetary settings."