Mathematical Digest

Short Summaries of Articles about Mathematics
in the Popular Press

"Streetcar Carries Evolution Modelers Around Roadblocks," by Nigel Williams.Science, 8 March 1996, pages 1365-1366.

This article discusses efforts by evolutionary biologists to use game theory tomodel evolution. In particular, some of these researchers have attempted tomodel ways in which genes could evolve over time to increase their evolutionaryfitness. Often, these models stall in an equilibrium state, even though thecombination of genes in the model is far from the fittest possible. Theoreticalbiologist Peter Hammerstein at the Max Planck Institute for Physiology andBehavior in Sweewiesen, Germany has tried to get around this problem with a newtwist on the model. He found that adding a large number of mutant genes has theeffect of kick-starting the system when it stalls in an equilibrium. This keepsthe evolutionary "streetcar" running forward, despite a few stopsalong its way. Some biologists believe that this model reflects well observedpatterns in evolution.

-Allyn Jackson