Scientists have found that rocks on and under the seafloor are a good habitat for microbes.
Click on image for full size
Courtesy of Nicolle Rager-Fuller/National Science Foundation

Rock Eating Bacteria Found at the Bottom of the Sea
News story originally written on May 28, 2008

Has anyone ever told you that you shouldn’t eat things that you find on the floor? Well, the rules are different for bacteria. Scientists have found tons of bacteria at the bottom of the ocean that appear to be “feeding” off the seafloor.

The deep seafloor used to be thought of as an extreme environment where life could not survive. But this is not the case. Scientists have found that areas of the seafloor that look deserted are actually teeming with living things – very tiny living things - bacteria.

Scientists have known for some time that there are bacteria down there, but they didn’t know how much. New research has figured out how many bacteria are living on the ocean floor. And there’s a lot.

Scientists found three to four times more bacteria living on rocks of the seafloor than in the waters above. They also found that the bacteria were very diverse – with many different species.

Surprised by this diversity, the scientists tested other places on the seafloor. They found diverse bacteria at the other locations too. So it seems likely that tons of bacteria are living all over the seafloor.

For living things to survive and grow they need a way to get energy. The researchers wondered where in this dark cold environment the bacteria were finding the energy they needed.

"We scratched our heads about what was supporting this high level of growth," said scientist Katrina Edwards.
From their research, they knew that the ocean crust supports more bacteria than seawater above it. The scientists hypothesized that the bacteria might be getting the energy they need from the rocks.

In the lab, they calculated how many bacteria could survive from the energy provided by reactions with the basalt rocks of the ocean floor. Then, they compared this calculation to the actual number of bacteria that they found down there. The numbers were similar, suggesting that the bacteria are able to get their nutrition from the rocks.

Last modified June 20, 2008 by Lisa Gardiner.

Shop Windows to the Universe Science Store!

Our online store includes books on science education, ranging from evolution, classroom research, and the need for science and math literacy!

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

The Scientific Process

How do scientists actually come up with explanations for the things that happen around us? The first step in this process happens when a scientist observes something happening that is both interesting...more

Basalt Rocks

Basalt is an extrusive igneous rock that is very dark in color. It is the most common type of rock in the Earth's crust and it makes up most of the ocean floor. It is made of many dark colored minerals...more

Life in the Deep Ocean

The deep ocean is very cold, under high pressure, and always dark because sunlight can not get down that far. Less life can survive in the deep ocean than in other parts of the ocean because of these conditions. ...more

Extreme Environments - Acid, Radiation, and More!

This page describes extreme environments that are filled with acids, are blasted with radiation, are under high pressure, or are tough places for most living things in various other ways. Extreme environments...more

Triggers of Volcanic Eruptions in Oregon's Mount Hood Investigated

Scientists have learned that Mount Hood, Oregon's tallest mountain, has erupted in the past due to the mixing of two different types of magma. "The data will help give us a better road map to what a future...more

Oldest Earth Mantle Reservoir Discovered

The Earth's mantle is a rocky, solid shell that is between the Earth's crust and the outer core, and makes up about 84 percent of the Earth's volume. The mantle is made up of many distinct portions or...more

It’s Not Your Fault – A Typical Fault, Geologically Speaking, That Is

Some geologic faults that appear strong and stable, slip and slide like weak faults, causing earthquakes. Scientists have been looking at one of these faults in a new way to figure out why. In theory,...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF