Leafcutter ants and fungus garden. (Image: Alex Wild, alexanderwild.com)

Nature walks can inspire serenity and, for the inquisitive mind, questions. Why are maples and ferns flourishing here together? Do they get along somehow? Why are there no maples on the other riverbank, where it’s mostly alder trees?

Such questions lie at the heart of ecology. Every biological system, whether a cell, an organism, a forest, or a society, can replicate and does so using resources collected from its environment. Population regulation – what’s living where and in what numbers – is a principal outcome of such interactions. The attempt to understand it has arguably been the organizing principle of the science of ecology.

“Almost every group in nature has some process involved in regulating its numbers,” says Stanford ecologist and SFI Science Board member Deborah Gordon, who specializes collective behavior in social insects. Some regulation models are based on centralized control or decentralized resource depletion, but scientists are finding that many systems blend the two.

In harvester ant colonies, for example, the queen doesn’t tell the others what to do. Rather, the rate an ant meets others and the information they exchange determine whether the ant should keep doing what it’s doing or switch to, say, foraging.

“No ant really knows how much food they have or need – that’s why it’s so interesting,” says Gordon. “They’re not all working toward a known or personal goal, yet they meet the goals of the colony.”

This emerging understanding of decentralized regulation prompted Gordon and University of Utah mathematical ecologist Frederick Adler to co-organize a working group, Centralized vs Decentralized Control in the Regulation of Populations, March 11&12, 2016, at SFI. 

During the meeting, researchers who study such topics as social insect colonies, cancer, and the city-states of ancient Greece are exploringe how centralized and decentralized control mechanisms interact to regulate physiological, social, and human systems. 

Participation in the working group is by invitation only.