Life's Starting Date Has Been Pushed Back Again

It’s not the red soil that makes NASA draw comparisons between Western Australia and Mars. It’s the age of the rocks. Rock formations in the Pilbara region are some of the oldest and best preserved on Earth. Researchers working in the area may have uncovered the oldest evidence of life on our planet, and it could aid in the search for life on the Red Planet.

An international team has uncovered evidence that microbes were living in complex communities 3.5 billion years ago, pushing back the geological record of such structures—and by extension, the origins of life itself—by almost 300 million years.

According to University of Western Australia researcher David Wacey, one of the researchers and authors of the study, they uncovered “microbially induced sedimentary structures” (MISS) in a body of rock called Dresser Formation, which are evidence of an early ecosystem of non-nucleated, single cell organisms.

"You can't see cells any more but what you can see is basically carbonaceous material which are the remnants of these cells," he told the Australian Broadcasting Company. "And, what's happened is that when they were alive they were interacting with the sediment where they were living and they were creating little communities where they were all kind of helping each other out to survive in what would have been a very harsh environment back then."

This harsh, early era on Earth—when the atmosphere was made of volcanic vapors and toxic gases like ammonia and methane were common—closely resembles what scientists think the early history of Mars was like. So the Mars rover is also searching for MISS evidence on the Red Planet. Evidence of early Earthbound life in MISS provides something of a roadmap for what NASA should keep its electric eyes peeled for.

"There are applications for searching for life elsewhere and knowing what to look for," Wacey told the Telegraph. "These microbial mats could be seen by a Mars rover… It also helps with our understanding of when life first evolved and what sort of environment it evolved in and putting firm dates on when some pretty important things happened.”