Bacteria are a very persistent form of life. They can be found in the most inhospitable places on Earth, such as the floor of the ocean. Bacteria are also very important for the biological processes that take place on Earth. This combination of importance and hardiness makes them one of the most successful life forms as well. The current theory for the origin of life suggests that the initial single-celled ancestors of all the life-forms on Earth might have originated at the bottom of the ocean as well. The evidence points to the fact that these single-celled organisms survived with the help of the heat from the cracks in the crust of the planet.
However, it is rare to find bacteria thriving hundreds of feet below the surface of the ocean. Therefore, it was received as a surprise when the news broke that researchers had found living cells in the ancient and cold volcanic rocks in the middle of the South Pacific Ocean. The biggest source of shock is the fact that these organisms have managed to survive in a place where their source of sustenance is not clear. With no clear source of sustenance and a very big population, these organisms have grabbed the attention of the scientific community. Researchers are still in disbelief over the discovery of these microbes.
This discovery has several long-reaching consequences on our understanding of the biological processes of the ocean. The biggest implication might be that the possibility that microbial life might be present throughout the oceanic crust. This is the most common form of the ocean floor and covers three-fifths of all oceans.
Its immense thickness characterizes it. Another, much broader implication of this discovery could be the fact that oceanic crust is found on Mars as well. We also know that Mars, at one point in time, had water on it. When these two pieces of information are put together, finding microbial life on Mars just got more probable.
The source of these oceanic crusts is volcanoes. The interaction of hot lava from these volcanoes forms the crust with the cold seawater. Composed primarily of Basalt, the reaction gives off energy that is essential for microbial life on the bottom of the ocean. However, this discovery means that microbial life, which is not anywhere near the site of the reaction, can also sustain themselves.
The scientists carefully extracted these rocks from the ocean floor and took them to their labs for studying. Normal seawater is teeming with microbial life; therefore, before cracking open the rocks to study the microbes insides, the researchers had to sterilize the rocks. What they found inside was extremely unexpected. The microbes inside lived in a highly dense community under a pressure of 580 atm. The preliminary studies show that the majority of the bacteria found in these rocks survive on organic material rather than hydrogen. The exact source of this organic matter could be either the carcasses of dead sea-life from above or from natural reactions in their vicinity.
The discovery goes to show just how persistent life is and how much more we have to learn about the nature of life itself.