Science Daily reports that a team working in the Frick Laboratory at Princeton has investigated the Electron Transport Chain (ETC) in mitochondria and believe it has found evidence that the protein chains involved in the transport generate mutations in response to suboptimal conditions by generating mutations, thus providing a positive feedback mechanism driving evolution.
A member of the team associate research scholar Raj Chakrabarti, says:
The discovery answers an age-old question that has puzzled biologists since the time of Darwin: How can organisms be so exquisitely complex, if evolution is completely random, operating like a ‘blind watchmaker’? Our new theory extends Darwin’s model, demonstrating how organisms can subtly direct aspects of their own evolution to create order out of randomness.
Their findings were published recently in Physical Review Letters.
The team identifies the underlying optimization process as a phenomenon in Control Theory known as “bang-bang extremization.” Chakrabarti explains:
In this paper, we present what is ostensibly the first quantitative experimental evidence, since Wallace’s original proposal, that nature employs evolutionary control strategies to maximize the fitness of biological networks. Control theory offers a direct explanation for an otherwise perplexing observation and indicates that evolution is operating according to principles that every engineer knows.