Bacteria Under Pressure?

The bottom of the ocean is not the most welcoming place, and that’s putting it mildly! There is essentially no sunlight, it is cold unless you’re near a hydrothermal vent, and the water is pressing down with unrelenting force. To top it all off, food is scarce and difficult to find. A creature has got to be pretty tough to live down there. However, it looks like more organisms exist there than we thought!

Recently, researchers Yuki Morono and coworkers were curious whether microbes could live in particularly inhospitable areas in the bottom of the ocean, where there are far less nutrients than the rest of the ocean floor. They conducted a thorough, careful investigation. They drilled to collect sediment samples from about 18,700 feet below sea level. The sediment cores were about 100 million years old. When the scientists did a chemical analysis, they noticed oxygen, which gave them hope that bacteria might be present. They added nutrients for any possible bacteria to consume. When they dissolved the sediment to take a closer look, their hopes were confirmed!

This finding just brings up more and more questions. If the sediment is over 100 million years old, how old are the bacteria? Perhaps they were dividing very slowly all this time- remember, bacterial cells divide before splitting into two separate cells. However, the idea of individual bacteria cells living to 100 million years seems unreasonable; they probably reproduced at some point. But what did they use for an energy source? Could it be radioactivity or something else?

This exciting discovery can help with further research about places we think are uninhabitable, such as outer space. If there are bacteria capable of surviving such tough conditions, who knows what other hardy life forms are out there?

Picture Source: scopeblog.stanford.edu/