Ecological stability, the ability of ecosystems to maintain their state despite external disturbances, has long puzzled scientists due to its defiance of mathematical predictions. Mathematical models suggest that larger, more complex ecosystems should be less stable due to the interdependence of their many parts. Yet, nature seems to contradict this, with larger ecosystems showing greater resilience.
A new theory, proposed by ecologists Stefano Allesina and Si Tang, offers an explanation. They argue that the traditional models, which assume that all species interact equally, are flawed. In reality, interactions are not equal; some are stronger than others. This unequal distribution of interaction strengths, they suggest, could be the key to ecological stability.
Their theory, known as the ‘weak interaction hypothesis’, was tested using data from 41 real ecosystems. The results showed that weaker interactions were indeed more common, supporting the hypothesis.
Despite this, the theory is not without its critics. Some argue that the data used is not representative of all ecosystems, while others question the assumption that weaker interactions lead to greater stability.
Nevertheless, the weak interaction hypothesis has sparked a new line of inquiry into the paradox of ecological stability, challenging traditional mathematical models and offering fresh insights into the complex workings of our natural world.
Go to source article: https://www.quantamagazine.org/how-nature-defies-math-in-keeping-ecosystems-stable-20180926/