Bacterial colonies survived two and a half years of complete isolation in the absence of food, almost not reducing: theoretically, they could have survived for a hundred thousand years.
Bacterial cells are known to survive the most extreme conditions, including those found on the surface of Mars and even in outer space. But bacterial populations show even more striking resistance. This is indicated by experiments conducted by scientists from Indiana University, which they talk about in an article published in the journal PNAS.
William Shoemaker and his colleagues selected 100 populations of bacteria representing 21 different taxa of heterotrophs - organisms that need organic matter for food and energy. They were placed in complete isolation for 1,000 days - more than two and a half years - after which they looked at what happened to the microbes. The number of all populations decreased, but this mainly happened in the first time after the start of the extreme hunger strike. Nevertheless, they all survived, and by the end of the 1000-day period, the number of many had stabilized, practically ceasing to decline.
The extrapolation performed by the authors of the work shows that theoretically these populations could have survived after 100 thousand years of such isolation. This is especially impressive when you think about the short life cycle of bacteria, which takes only a few hours to change generations. In addition, experience once again points to the possibility of "returning to life" of microbes that have been lying in the permafrost for thousands of years.
Due to starvation in the experiment, some cells sharply reduced the activity of metabolic processes, while others completely formed inert spores - a form that allows them to survive in the most unfavorable conditions. However, scientists consider cannibalism to be the main secret of survival. A part of the population that died in the first hours and days after the start of a long hunger strike formed a "necromass" of organics, which the survivors could gradually feed on until the size and energy balance of the entire population stabilized.