First Martian life likely broke the planet with climate change, made themselves extinct

Ancient microbial life on Mars could have destroyed the planet's atmosphere through climate change, which ultimately led to its extinction, new research has suggested. The new theory comes from a climate modeling study that simulated hydrogen-consuming, methane-producing microbes living on Mars roughly 3.7 billion years ago. The model suggests that the reason life thrived on Earth and was doomed on Mars is because of the gas compositions of the two planets, and their relative distances from the sun.

Being farther away from our star than Earth, Mars was more reliant on a potent fog of heat-trapping greenhouse gases, such as carbon dioxide and hydrogen, to maintain hospitable temperatures for life. So as ancient Martian microbes ate hydrogen and produced methane they slowly ate into their planet's heat-trapping blanket, eventually making Mars so cold that it could no longer evolve complex life. As Martian surface temperatures dropped from a tolerable range between 68 and 14 degrees Fahrenheit to a punishing minus 70 F, the microbes fled deeper and deeper into the warmer crust of the planet - burrowing more than 0.6 mile deep only a few hundred million years after the cooling event.

Traces of methane have been detected on Mars' sparse atmosphere by satellites, as well as in the form of 'alien burps' spotted by NASA's Curiosity rover, which could be evidence that the microbes still exist. The scientists believe their findings suggest that life may not be innately self-sustaining in every conducive environment it pops up in, and that it can easily wipe itself out by accidentally destroying the foundations for its own existence. "The ingredients of life are everywhere in the universe," study lead author Boris Sauterey, an astrobiologist at the Institut de Biologie de l'Ecole Normale Supérieure in Paris, France told Space.com. "So it's possible that life appears regularly in the universe. But the inability of life to maintain habitable conditions on the surface of the planet makes it go extinct very fast. Our experiment takes it even a step farther as it shows that even a very primitive biosphere can have a completely self-destructive effect."

Source : LiveScience