A new study suggests that germs that have been dormant for millions of years may be able to regenerate, raising intriguing new questions about the nature of life.
According to an article published in Nature, a research team led by the Japan Agency for Marine-Earth Science and Technology conducted experiments on sediment samples deposited from the South Pacific over 100 million years ago. Because sediment contains few nutrients, in theory the area would not be hospitable to life forms. Yet scientists were able to regenerate almost all microorganisms in the samples through an incubation process, indicating that they may be able to survive in a dormant state for millions of years due to traces of oxygen within the sediment.
An important factor in understanding the importance of the study? Were able to survive fewer microbes in the ocean than microbes on the surface. This may help explain how they could have lived under specific hostile conditions of deep-sea sediment, although it adds to the mystery of how the same microbes could have been accommodated for life on the surface.
“The main relevance of this study is that it challenges’ understanding the rules of life,” Steven D’Hondt, a geologist who contributed to the study, told Salon by email. “It is not yet understood how any community of any kind of organisms can survive for so long at such a low energy and then return to normal activities when they return to the conditions of the surface world. “
He said, “The most important contribution to our understanding of ancient life is the demonstration that ancient life still exists in the world. I say this because these subpopulation populations probably have not reproduced at very rapid rates or they Many new mutations have accumulated. ” was buried. “
A particularly notable description of the study, as the authors wrote in their paper, is that “sample communities are probably trapped in sediment immediately after their deposition. The physical condition and growth potential of these buried communities, and generally . The portions of these energy-hungry subclass microorganisms that are alive, dormant or dead are essentially unknown. “
Virginia Edgomb, a microbial ecologist at the Woods Hole Oceanographic Institution who did not participate in the study, told Science magazine that the study indicated that “microbial life is very permanent and often finds a way to survive.”
Another scientist who was not involved in the study, Microbiologist Andreas Tuske of the University of North Carolina, told the magazine that “if the surface of a particular planet does not look promising for life, it may be out in the subsurface.”
Salon asked D’Hondt whether the germs found in the sediment possessed all the qualifications to be “alive”. This is not always a cut-and-dried question, as there is a vigorous debate among scientists over whether microbes such as viruses can technically be considered a form of “life”. However, D’Hondt was convinced that these microbes had made the cut.
D’Hondt told Salon, “Generally, something is considered alive if it can produce, breed and harvest energy on its own.” “As shown in our paper, Yuki Morono’s experiments showed directly that 99% of the germs in our burial communities did these things (energy, reproduction and crop energy).”
Asked whether the experiments could bring about real-world expressions of science fiction scenarios – such as the premise of “Jurassic Park”, in which dinosaurs were brought back from extinction – they had deep doubts.
“I think it’s conceivable that one could revive something like yeast in this way,” he replied. “But something like a ‘Jurassic Park’ landscape (eg, living dinosaurs) would still require recreation of dinosaurs rather than a revival of living organisms (like our bacteria).”