Vast, zombie-like microbial life lurks beneath seabed
TAMPA: Scientists have drilled 2.5km beneath the seabed and found vast underground forests of “deep life”, including microbes that persist for thousands, maybe millions of years, researchers said.
Feeding on nothing but the energy from rocks, and existing in a slow-motion, even zombie-like state, previously unknown forms of life are abundant beneath the Earth despite extreme temperatures and pressure.
About 70% of Earth’s bacteria and archaea – single-celled organisms with no nucleus – live underground, according to the latest findings of an international collaboration involving hundreds of experts, known as the Deep Carbon Observatory.
This “deep life” amounts to between 15 and 23 billion tonnes of carbon, said the DCO.
“The deep biosphere of Earth is massive,” said Rick Colwell, who teaches astrobiology and oceanography at Oregon State University.
He described the team’s findings so far as a “very exciting, extreme ecosystem”.
Among them may be Earth’s hottest living creature, Geogemma barossii, a single-celled organism found in hydrothermal vents on the seafloor. Its microscopic cells grow and replicate at 121°C.
“There is genetic diversity of life below the surface that is at least equal to but perhaps exceeds that which is at the surface and we don’t know much about it,” Colwell said.
Similar types of strange, deep life microbes might be found on the subsurface of other planets, like Mars.
“Most of deep life is very distinct from life on the surface,” said Fumio Inagaki, of the Japan Agency for Marine- Earth Science and Technology.
“The microbes are just sitting there and live for very, very long periods of time,” he said.
Brought up from these ancient coal beds and fed glucose in the lab, researchers have seen some microbes, bacteria and fungi slowly waking up.
“That was amazing,” said Inagaki. Scientists have found life in continental mines and boreholes more than 5km deep, and have not yet identified the boundary where life no longer exists, he added. — AFP