Airdate: Jan 18, 2007
Scientist: Prof. Derek Lovley
Geobacter - Origins of Life
A recently discovered group of hardy microorganisms are giving scientists clues to the evolution of life on earth.
Recently, a microorganism was discovered which thrives at extremely high temperatures. It's giving scientists clues to the origins of life on earth and possibly - other planets. I'm Jim Metzner and this is the Pulse of the Planet.
"The implications of a microorganism being able to grow at 121 degrees C, is that it expands the window of where we know life might exist. This has importance not only for understanding life on earth, but also if we're going to be looking for life on other planets, such as Mars, it says we can look at temperatures up to 121 degrees and still expect at least life as we know it in that temperature range."
Derek Lovely is a professor of microbiology at the University of Massachusetts in Amherst. He's talking about a microbe called Strain 121 - so named because it can survive at 121 degrees centigrade. Instead of breathing oxygen, Strain 121 grows on hydrogen and iron.
"Strain 121 and other organisms like it that can grow on iron at high temperature, have implications for the evolution of life. Geologists tell us that prior to the existence of life, there was a significant amount of hydrogen and iron on earth and that this is probably the type of reaction by which life might first have evolved."
Whether we're searching on earth or on Mars, where would you expect to find this kind of microorganism?
"Underneath the surface of earth, it's teeming with microorganisms. wherever there's liquid water and some type of energy source you find microorganisms"
"What we know about the temperature on Mars in terms of life, is that the surface is very cold, but deeper below the surface of Mars, where's there's likely to be liquid water, the temperatures could be significantly higher. This tells us that we can look into environments as high as 121 degrees C and expect that there might be life in that type of temperature."
Pulse of the Planet is presented by the National Science Foundation. I'm Jim Metzner.