The research, published in a recent edition of Physical Review Letters, provides corroborating data, Rabitz said, for Wallace's idea. "What we have found is that certain kinds of biological structures exist that are able to steer the process of evolution toward improved fitness," said Rabitz, the Charles Phelps Smyth '16 Professor of Chemistry. "The data just jumps off the page and implies we all have this wonderful piece of machinery inside that's responding optimally to evolutionary pressure."
The authors sought to identify the underlying cause for this self-correcting behavior in the observed protein chains. Standard evolutionary theory offered no clues. Applying the concepts of control theory, a body of knowledge that deals with the behavior of dynamical systems, the researchers concluded that this self-correcting behavior could only be possible if, during the early stages of evolution, the proteins had developed a self-regulating mechanism, analogous to a car's cruise control or a home's thermostat, allowing them to fine-tune and control their subsequent evolution. The scientists are working on formulating a new general theory based on this finding they are calling "evolutionary control."
The work is likely to provoke a considerable amount of thinking, according to Charles Smith, a historian of science at Western Kentucky University. "Systems thinking in evolutionary studies perhaps began with Alfred Wallace's likening of the action of natural selection to the governor on a steam engine --- that is, as a mechanism for removing the unfit and thereby keeping populations 'up to snuff' as environmental actors," Smith said. "Wallace never really came to grips with the positive feedback part of the cycle, however, and it is instructive that through optimal control theory Chakrabarti et al. can now suggest a coupling of causalities at the molecular level that extends Wallace's systems-orien
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| Contact: Kitta MacPherson kittamac@princeton.edu 609-258-5729 Princeton University Source:Eurekalert |