"The idea that has been dominant for the last couple of decades is that when two species co-evolve, they try to outrun each other," said Carl Bergstrom, a University of Washington assistant zoology professor. But that doesn't necessarily hold true for individuals of different species engaged in a mutualistic, or symbiotic, relationship. In such cases, he said, the one that evolves more slowly is likely to gain a disproportionate share of benefits from the relationship.
A predator, for example, typically must evolve rapidly so that it doesn't fall behind the evolutionary advances of its prey and thus miss lunch. That has been termed the "Red Queen effect" after the character in Lewis Carroll's "Through the Looking Glass," who said, "It takes all the running you can do to keep in the same place."
Bergstrom and Michael Lachmann, a postdoctoral researcher at Germany's Max Planck Institute for Mathematics in the Sciences, have given the name "Red King effect" to mutualistic relationships in which greater benefits go to the slower-evolving species. Their findings are being published this week in the Proceedings of the National Academy of Sciences.
The effect is particularly pronounced if, in the course of "bargaining," one side has little room to negotiate and so the other side is forced to give up more if the two are to continue their relationship, according to the researchers, who have been collaborating for nearly a decade.
For instance, one might imagine the Red King and Red Queen on opposite sides of a chessboard, with the slow-and-patient king and the fast-but-impatient queen negotiating where to meet. Each wants the other to trave
Contact: Vince Stricherz
University of Washington