finding mathematical order in ecology South East, 1970

Robert May. Royal Society.

Ecologists are interested in how populations, communities and ecosystems change. Mathematical models have become increasingly useful for understanding the significance of these changes.

Popular thinking had been that the more diverse a population the more stable it is, but in 1973 Robert May (1938- ) demonstrated that this was not the case. In his influential book ‘Stability and Complexity in Model Ecosystems’ May showed that, on the contrary, communities with high biological diversity, such as a tropical rainforest, are often more vulnerable to disturbance than simpler systems.

This new approach to ecology led May in 1974 to a branch of mathematics called Chaos Theory, the powerful and subtle mathematical idea that simple equations can generate apparently random behaviour. May found that the waxing and waning of animal populations to the incidence of disease reflect a deep mathematical order and that tiny changes in the starting conditions of a population of organisms lead to colossal, unpredictable differences in the results, the so-called ‘butterfly effect'.