Astrobiologist Sara Walker is exploring ways to measure the transition from non-living to living matter. Her approach could broaden our understanding of how unique--or common--life might be in the Universe.
The story of life's origin is one of the great unsolved mysteries of science. The puzzle boils down to bridging the gap between two worlds--chemistry and biology. We know how molecules behave, and we know how cells work. But we still don't know how a soup of lifeless molecules could have given rise to the first living cells.
"It's a really tough problem," says Sara Walker, an astrobiologist at Arizona State University. But she thinks it can be cracked. In fact, she believes there may be a way to measure the transition from non-life to life.
In February, Dr. Walker presented the inaugural lecture for the NASA Astrobiology NPP seminar series. In a talk titled "Information Hierarchies, Chemical Evolution and the Transition from Non-Living to Living Matter," she described some of the models she developed as a NASA postdoctoral fellow.
These models set up the conceptual framework for measuring the emergence of life, a goal she's now pursuing as an assistant professor at the School of Earth and Space Science and the Beyond Center for Fundamental Concepts in Science at ASU.
She began her talk with a quote from the Harvard chemist George Whitesides, which captured nicely the gap she is trying to bridge: "How remarkable is life?" he asked. "The answer is: very. Those of us who deal in networks of chemical reactions know nothing like it."
If it succeeds, Walker's approach could broaden our view of what life is, and help us figure out whether its emergence on Earth is merely a fluke or the product of some universal laws.
The seminar is now available here to watch online.
To read more about the research Sara Walker discussed, visit the Astrobiology Magazine.
The next talk in the Early Career Seminars series will be held on April 7, 2014,at 11am PDT. Paula Welander of Stanford University will present, "Hopanoid Biosynthesis and Function in Methanotrophic Bacteria."