May 07, 2003

Why Nature Is, After All, Worth Reading Every Week

I've heard it said that if Nature accepts your paper the first time around, you should find a new research area, because within five years your present topic will be dead. (And the person who said that had papers there.) But still, where else can one go from an editor's review of the new X-Men movie ("The X-Men are a band of superheroes (Homo sapiens superior) who possess a mutated X gene, which has an extraordinarily variable phenotype.... The X gene's normal function is not revealed") to electronic paper, to re-designing receptor enzymes to recognize arbitrary chemicals (and an explanation of why that matters), to something which should've been titled "Nature to Creationists: Drop Dead"?

The evolutionary origin of complex features

Richard E. Lenski, Charles Ofria, Robert T. Pennock and Christoph Adami

A long-standing challenge to evolutionary theory has been whether it can explain the origin of complex organismal features. We examined this issue using digital organisms --- computer programs that self-replicate, mutate, compete and evolve. Populations of digital organisms often evolved the ability to perform complex logic functions requiring the coordinated execution of many genomic instructions. Complex functions evolved by building on simpler functions that had evolved earlier, provided that these were also selectively favoured. However, no particular intermediate stage was essential for evolving complex functions. The first genotypes able to perform complex functions differed from their non-performing parents by only one or two mutations, but differed from the ancestor by many mutations that were also crucial to the new functions. In some cases, mutations that were deleterious when they appeared served as stepping-stones in the evolution of complex features. These findings show how complex functions can originate by random mutation and natural selection.

This quite redeems Adami for his tautologous papers on "physical complexity".

Biology ; Complexity

Posted at May 07, 2003 16:15 | permanent link

Three-Toed Sloth