Jakarta –
Beneath our feet, deep in the depths of our planet, lies an immense, colossal ecosystem teeming with life. In recent years, an international team of scientists has uncovered how billions upon billions of microorganisms live thousands of kilometers beneath the surface Earth.
Presenting their findings at the annual meeting of the American Geophysical Union in 2018, the researchers quantified the size of this mysterious treasure of life for the first time, and it’s much larger than they previously thought.
They report that about 70% of the total number of microbes on the planet live underground. In total, these microbes represent an estimated 15 to 23 billion tons of carbon, hundreds of times greater than the carbon mass of all humans on the surface.
It is estimated that only a few are known. It’s like scientists have only scratched the surface when it comes to describing these microorganisms. However, the first glimpses of this study suggest that the genetic diversity of life below Earth’s surface may be comparable to, or even exceed, that of life above the surface. This is why this ecosystem is nicknamed the ‘underground Galapagos’.
However, don’t imagine creatures like turtles or other easily visible animals living down there. Life below Earth’s surface is dominated by bacteria and their evolutionary cousins, the archaea. But the researchers also recorded quite a lot of eukarya down there. For example, researchers described an unidentified nematode 1.4 kilometers deep in a South African gold mine.
“Ten years ago, we sampled only a few sites, the types of places we would expect to find life,” said Karen Lloyd, study author and Associate Professor of microbiology at the University of Tennessee, in a 2018 statement, quoted detikINET from IFL Science.
“Now, thanks to ultra-deep sampling, we know we can find them almost everywhere, even though sampling clearly reaches only a very small part of the deep biosphere,” added Professor Lloyd.
To reach these findings, the team brought together dozens of studies that looked at samples taken from drilling between 2.5 and 5 kilometers into the Earth’s crust, on both the ocean floor and inland continents. Also, to their surprise, they found that the deep subsurface biosphere is almost twice the volume of all the oceans.
This finding is truly astonishing considering that the living things brought there were exposed to intense heat, crushing pressure, no light, and almost no nutrients. It is impossible for life to exist, let alone such diverse ecosystems, to inhabit a place with such extreme conditions. Still, researchers say these ecosystems can answer many questions about the limits of life on Earth and beyond.
“Our study of deep biosphere microbes has led to a wealth of new knowledge, but also a much greater realization and appreciation of how much we have to learn about life below Earth’s surface,” added Rick Colwell, microbial ecologist at Oregon State University.
“For example, scientists do not yet know all the ways in which deep subsurface life influences surface life and vice versa. And, for now, we can only admire the metabolic properties that allow life to survive under very extreme conditions, conditions for life in Deep Earth,” he concluded.
Watch Video “Revealing Life 2 Million Years Ago Through the Oldest DNA“
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