Crowds of Ancient Bacteria Found Living Underneath the Seafloor of the South PacificPlanet Earth
Scientists were shocked to discover massed colonies of bacteria thriving on pieces of organic matter under 100-million-year-old rocks deep in the South Pacific seafloor.
One study discovered 10 billion organisms with a single cell crammed in a 1-cubic-centimeter space which is similar to the density of bacteria in the human stomach. Since the samples were taken from hydrothermal vents, the organisms weren’t washed away by currents into the crevices.
According to the researchers, there is a high possibility that they multiplied there for millions of years, feeding on the clay from the crevices. Many experts have hypothesized that organisms can be found underneath in rocks from the seafloor. However, finding evidence has been difficult.
A group of researchers from the University of Tokyo used a different approach to look for single-cell organisms from the rock crevices. Instead of pulverizing, they applied a special epoxy on the sample collected and cut them into very thin slices.
When the epoxy preserved the tiny crevices, they stained the slices using fluorescent dye to find microbial DNA. From this, they were able to find out that the organisms were surrounded by clay with organic carbon which is their source of nutrients.