Life on Earth began in . . . Greenland!?

Now known as one of the most inhospitable places on Earth, the giant arctic island of Greenland might actually hold the birthplace of all life on Earth. Yes, all life on Earth might well have sprang from Greenlandic mud volcanoes.

The Isua region of southwest Greenland is home to a number of these mud volcanoes, which researchers at the Laboratory of Geology in Lyon, France believe erupted 3.8 billion years ago. These eruptions forced up to the surface some chemical elements crucial to the formation of biomolecules. This probably wasn't the first or last time that that sequence of events occur, but the researchers argue that, in this particular instance, conditions were aligned perfectly for the emergence of life...and 3.8 billion years later, here we are.

This new hypothesis is an alternative to the current leading theory, which says life began in hydrothermal vents known as black smokers. These vents, found at the bottom of the ocean, do contain the perfect mixture of hydrogen, methane, and ammonia necessary to support the emergence of life, but the extreme acidic nature of the black smokers makes amino acid stabilization very difficult, which in turn would likely preclude the formation of life.

The researchers studied samples of the mineral serpentinites found in Isua that date back 3.8 billion years. These minerals show that they formed in a highly non-acidic environment, meaning amino acid stabilization would have been a breeze. What's more, the oceanic crust of Isua had all the hydrothermal fluids, carbonates, and phosphorus needed to jump-start the formation of complex biomolecules...and since all those together combine to form mud volcanoes, it seems these volcanoes were the ideal place for life to first emerge.

What's particularly interesting about all this is that it implies life began on land, not in the oceans, as Isua was part of the tiny scrap of continental landmass present above water 3.8 billion years ago. Considering that almost all of the ancient Earth was covered in oceans, it would make sense that these earliest lifeforms would leave the mud volcanoes, but it all suggests a rather fascinating thought - the billions of years our ancestors spent living in the sea might actually have been a gargantuan evolutionary detour, one long holding pattern before we evolved the capacity to return to the land from which we originated. There's no way to know for sure, but it's a seriously intriguing thought.

Via PNAS. Image by Stig Nygaard on Flickr.