Though a serviceable, if still developing, theory of the evolution of life exists, almost nothing is known about the very initial stages of the process. In these initial stages, known as prebiotic evolution, chemical systems appeared which were sufficiently lifelike for biological evolution to begin. In this talk I will begin with a brief discussion why a better understanding of the process of prebiotic evolution is crucial for any kind of rational estimate of the likelihood that humans will observe extraterrestrial life. Then I will describe the paradox, often attributed to Manfred Eigen, which plagues the simplest, 'naked gene' models for prebiotic evolution, demonstrating that this is essentially a problem in statistical physics. I will describe a class of models, associated with Stuart Kauffman and others, which avoid the paradox. Finally I will describe our work on a variant of the latter models, in which the imposition of the constraint that life-like systems are not in chemical equilibrium leads to qualitatively new results. In particular, our results suggest that deserts might be better than ponds for initiating life. A few details of the models and simulations will be described as time allows.
Reference: A. Wynveen, I. Fedorov, and J. W. Halley, Nonequilibrium steady
states in a model for prebiotic evolution, Physical Review E 89 , 022725
(2014)
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