Very old microbes discovered deep below earth surface

Relatively diverse microorganisms exist below the Earth’s surface which was incredible to know that they grow at a very slow pace.Long-lived bacteria known to be around 100million years old, reproducing once in every 10,000years, present in rocks which are 2.5Km below the ocean floor. Along with these long lived bacteria viruses and fungi are also been discovered. This is often rises question among the researchers that how life persists in such extreme conditions.

Viruses exist in rocks deep beneath the ocean floor all over the globe


Scientists from the Integrated Ocean Drilling Program have announced the findings at the Goldschmidt conference, a meeting of more than 4,000 geochemists, in Florence, Italy.
Microbes does exist in a very low concentrations of around 1000 in every teaspoon of rock, comparing with the trillions present on the earth’s surface – as reported by Fumio Inagaki of the Japan Agency for Marine-Earth Science and Technology.

Leaving back the bacterial counts in the deep rocks, viruses are more abundant. They are outnumbering microbes more than 10 to one, with the increasing ratio to depth. This was reported by Tom Englehardt of the University of Oldenburg, Germany. Viruses are found to be more stable in the sediments. Since the metabolic rates of the cells are so low, they are known to be present from 100 million years.

Scientists were much surprised to find out how such low concentration of microbes with large generation gap compared with the communities on the Earth’s surface is able to support virus’ life cycle. It is also incredible to understand how these microbes have such enough energy to live so long life.

The long lived bacteria metabolize so slow that it arises question whether they even constitute life at all. Earth scientists suggested such long lived microbial communities deep inside the earth’s surface could bring about change in the chemistry of rocks, the deeper earth, and even the planet itself. Locking up many questions, scientists are in a new quest to journey towards deep understanding about these “zombie” microbes and their interaction towards the sustainability of the earth’s chemistry.


Story source: BBC News Science and Environment