The Continuing Adventures of the Blind Locksmith: You Can't Get There From Here

Three years ago, I wrote a series of blog posts about how scientists at the University of Oregon reconstructed the 450-million-year history of a protein. You can read the posts here, here, and here. What was particularly elegant about the study was how the scientists recreated the ancestral protein as it existed over 400 million years ago, to see how it functioned. Then they pinpointed the mutations that transformed the protein, shifting it from an old function to a new one. Recently, the scientists tried to run their experiment backwards. They tried to turn the new protein back into the old one. And they failed. In that failure, they've discovered something important. They argue that when it comes to evolution, you can't go home again. In today's issue of the New York Times, I describe this new research, which was recently published in Nature. (Check out the web page of the lead author, Joseph Thornton, for pdf's of all his papers on this paleoprotein project.)