An interdisciplinary team of scientists at Michigan State University and the California Institute of Technology, with the help of powerful computers, has used a kind of artificial life, or ALife, to create a road map detailing the evolution of complex organisms, an old problem in biology.

In an article in the May 8 issue of the international journal Nature, Richard Lenski, Charles Ofria, Robert Pennock, and Christoph Adami report that the path to complex organisms is paved with a long series of simple functions, each unremarkable if viewed in isolation.

Moreover, the article states, some mutations that cause damage in the short term ultimately become a positive force in the genetic pedigree of a complex organism.

"The little things, they definitely count," said Lenski, MSU Hannah Distinguished Professor of Microbial Ecology and the paper's lead author. "Our work allowed us to see how the most complex functions are built up from simpler and simpler functions. We also saw that some mutations looked like bad events when they happened, but turned out to be really important for the evolution of the population over a long period of time."

In the key phrase, "a long period of time," lies the magic of ALife. Lenski teamed up with Adami, a faculty associate and principal scientist at Caltech's Jet Propulsion Laboratory and Ofria, an MSU assistant professor of computer science and engineering, after a chance meeting with a colleague on the squash court led him to hear a seminar about their work.

Their first Nature paper on digital evolution was published in 1999. Pennock, an MSU associate professor of philosophy, now joins the team as they study an artificial world inside a computer, a world in which computer programs take the place of livi
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Contact: Richard Lenski
lenski@msu.edu
517-355-6463 x1603
Michigan State University
7-May-2003