Look beneath your feet for origins of life
Planet bursting with ‘awe-inspiring’ life forms that take up twice volume of all the world’s oceans
Earth is teeming with life miles beneath the surface, leading to speculation that our distant ancestors may have evolved deep underground. Barely living “zombie” bacteria and tiny worms have been discovered more than three miles into the planet’s crust.
EARTH is teeming with life miles beneath the surface, leading to speculation that our distant ancestors may have evolved deep underground.
Barely-living “zombie” bacteria and tiny worms, inhabiting entirely new ecosystems more than three miles into the planet’s crust, have been discovered by researchers at the Deep Carbon Observatory (DCO).
The life forms, some oddly striking, are so numerous they would fill up twice the volume of all the world’s oceans and is so diverse that it has been dubbed a “subterranean Galapagos”, with tiny creatures which can live at temperatures up to 249F (121C) existing on strange diets of rock and methane.
“They are not Christmas ornaments, but the tiny balls and tinsel of deep life look like they could decorate a tree as well as Swarovski glass,” said Dr Jesse Ausubel, of The Rockefeller University. “Why would nature make deep life beautiful when there is no light, no mirrors?”
The team, which includes scientists from Oxford and Bristol universities, and University College London, drilled into the seabed and searched the world’s deepest mines looking for microbes well within the planet.
Some life forms have existed for millions of years without replicating – meaning scientists may need to rewrite the fundamental concept that all cellular life can be divided into three domains of archaea, bacteria and eukaryotes.
Dr Mitch Sogin, co-chairman of the Marine Biological Laboratory in Massachusetts, said: “Exploring the deep subsurface is akin to exploring the Amazon rainforest.
“There is life everywhere, and everywhere there’s an awe-inspiring abundance of unexpected and unusual organisms. Molecular studies raise the likelihood that microbial dark matter is much more diverse than what we currently know it to be, and the deepest branching lineages challenge the three-domain concept introduced by Carl Woese in 1977.”
The researchers, who presented their findings at the American Geophysical Union’s annual meeting, are hoping their work could help answer the question of whether life started deep in the Earth, possibly in hydrothermal vents, before migrating up towards the Sun. They also want to find out how life below the surface influences that above.
Finding organisms which can exist in the deepest, darkest places on Earth might will help those looking for microbes on other planets understand the conditions that can support life.
“Our studies of have produced much new knowledge but also a realisation and far greater appreciation of how much we have yet to learn about subsurface life,” said Dr Rick Colwell, of Oregon State University.