Bubblecar said:
The Earth is far more alive than previously thought, according to “deep life” studies that reveal a rich ecosystem beneath our feet that is almost twice the size of that found in all the world’s oceans.
Despite extreme heat, no light, minuscule nutrition and intense pressure, scientists estimate this subterranean biosphere is teeming with between 15bn and 23bn tonnes of micro-organisms, hundreds of times the combined weight of every human on the planet.
….“It’s like finding a whole new reservoir of life on Earth,” said Karen Lloyd, an associate professor at the University of Tennessee in Knoxville. “We are discovering new types of life all the time. So much of life is within the Earth rather than on top of it.”
The team combines 1,200 scientists from 52 countries in disciplines ranging from geology and microbiology to chemistry and physics. A year before the conclusion of their 10-year study, they will present an amalgamation of findings to date before the American Geophysical Union’s annual meeting opens this week.
Lloyd said: “The strangest thing for me is that some organisms can exist for millennia. They are metabolically active but in stasis, with less energy than we thought possible of supporting life.”
Rick Colwell, a microbial ecologist at Oregon State University, said the timescales of subterranean life were completely different. Some microorganisms have been alive for thousands of years, barely moving except with shifts in the tectonic plates, earthquakes or eruptions.
Full report
The report begs the question. Which deep?
Subterranean bacteria have previously been known from soil, aquifers, mines, salt mines, caves, and oil wells. It gives me hope for the future of life on Earth after humans have destroyed everything on the surface.
> The scientists have been trying to find a lower limit beyond which life cannot exist, but the deeper they dig the more life they find. There is a temperature maximum – currently 122C.
70% is only twice as found on the surface. Since the space underground is so vast, they must be few and far between.
The original press release is here, with links to the scientific papers.
https://deepcarbon.net/life-deep-earth-totals-15-23-billion-tonnes-carbon
- The genetic diversity of life below the surface is comparable to or exceeds that above the surface
- certain genera and higher taxonomic groups are ubiquitous – they appear planet-wide
- in older sediments, food energy has declined over time, reducing the microbial community
- ever-increasing accuracy and the declining cost of DNA sequencing, coupled with breakthroughs in deep ocean drilling technologies (pioneered on the Japanese scientific vessel Chikyu)
- Ten years ago, we had sampled only a few sites—the kinds of places we’d expect to find life. Now, thanks to ultra-deep sampling, we know we can find them pretty much everywhere
> Movement: How does deep life spread—laterally through cracks in rocks? Up, down? How can deep life be so similar in South Africa and Seattle, Washington?
> Origins: Did life start deep in Earth?
> Energy: Is methane, hydrogen, or radiation from uranium the most important energy source for deep life?