Have you ever thought about what lies beneath our feet in the sheer depths of our planet? According to scientists, it’s an incredibly vast ecosystem swarming with life. After observations during the past few years, a large group of international scientists recently revealed that several billions of microorganisms live miles beneath the subsurface of the Earth.
The group of scientists presented their work in 2018 at the annual meeting of the American Geophysical Union. For the first time, they calculated the size of this mysterious treasure trove of under-surface life during their research. According to the group, it was way bigger than they ever expected! As per the presented report, around 70% of the total microbes on this planet use to live underground. Cumulatively, these microbes represent approximately 15-23 billion tonnes of carbon in total. Astonishingly, this number is hundreds of times greater than the total carbon mass of humankind living on the Earth’s surface. Also, this deep subsurface biosphere is surprisingly almost twice the volume of all oceans.
First glances suggest that the massive genetic diversity of microorganisms living below the surface can be comparable to, or possibly even exceed, the life living above the surface. For this reason, scientists have nicknamed this under-subsurface ecosystem the “subterranean Galapagos.” According to them, mainly bacteria and archaea, the evolutionary cousins of bacteria, dominate beneath the surface, with a fair number of eukarya too.
To reach the definitive findings, the team of researchers brought together several dozen studies, including samples unearthed by drilling 1.55-3.1 miles (2.5-5 kilometers) into the Earth’s crust, in the inland continents, and the seafloor as well. The subsurface of the Earth is the place where one can hardly expect to find life thriving, especially due to crushing pressures, intense heat, and scarcity of light and nutrients. That’s why the researchers hope that this newly found ecosystem can deliver a greater knowledge of subsurface life, and help push the limits of life on Earth and beyond.