New mathematical studies of the interactions between oscillating biological populations may shed light on some of the toughest questions in ecology, including the number and types of species in an ecosystem, according to an article in the December 2006 issue of BioScience. The article, by John Vandermeer of the University of Michigan, shows how extensions of established theory suggest that many animal and plant populations oscillate in synchrony because of interactions such as predation and competition. Such synchronization can have far-reaching effects. Vandermeer suggests that several well-known biological conundrums, such as the higher-than-expected diversity of plankton in aquatic ecosystems, may be explained this way.

Physicists know that even a weak coupling between oscillating systems can yield synchronized oscillations, a phenomenon that was studied with pendulums by the seventeenth century Dutch mathematician Christiaan Huygens. Biologists have only in recent years started to explore the implications for their subject. But it is already clear that coupled oscillating biological populations can give rise to potentially important effects such as synchronized chaos: the interaction between two weakly competing consumers of a food resource can be transformed by the arrival of a third competitor to provide unpredictable opportunities for the newcomer to invade. Vandermeer holds out hopes that the study of oscillations in biological populations will lead to insights into complex systems, such as those that include animals that eat other predators as well as omnivores that eat both predators and those predators prey.