All life that we see on Earth originated from a population of organisms that biologists call the Last Universal Common Ancestor — a single-celled life form that likely lived off the energy in deep-sea hydrothermal vents. Though all organisms carry traces of this billions-year old ancestor in our DNA, we know very little about how life's progenitor emerged in the first place. How did the originator . . . originate?
A group of biologists think that a new synthesis in evolutionary theory might help answer this question. The working group, meeting November 13-15 at SFI, is part of SFI’s ongoing Research Coordination Network for Exploration of Life’s Origins, sponsored by NASA and the National Science Foundation. In the spirit of the larger research program, the November meeting brings together evolutionary theorists and experimentalists to explore which evolutionary models might best explain how chemical systems become biological systems.
The group will ask not only about the import of existing models; it will also ask what is missing from current theories that could account for selection-like processes in prebiotic systems that are the precursors to adaptive evolution.
Generating a theory that bridges chemistry and biology entails “thinking about chemical evolution in a new way,” says SFI Professor Chris Kempes, who is co-organizing the group with geneticist David Baum of the University of Madison and computational biologist Oana Carja of Carnegie Mellon University. Since Kempes is a theoretical physical biologist who often works on astrobiology, he’s ultimately interested in arriving at “general principles for life anywhere in the Universe.”
For Carja, the workshop will be a forum to explore whether, and how far, her research on the spatial and temporal constraints on evolution can apply in a prebiotic context. “Can we use existing evolutionary theory to understand the precursors to life?” Carja asks, “Or are conditions so different that we need entirely new frameworks?” Advancing a theory of life’s origins could also push experimental models one step further. Experimentalists have yet to recreate chemical systems capable of adaptive evolution. With better theories, models, and simulations, however, we may be able to develop new experiments that move from generating life’s building blocks, to simulating the chemical process that bring about evolving life as we know it.