Tackling the great paradox of biodiversity with game theory
https://phys.org/news/2018-08-tackling-great-paradox-biodiversity-game.html
Scientists have always wondered how thousands of species can coexist in environments that have limited resources and can’t sustain for everyone. Also, now that preserving biodiversity is on top of many people’s priority list, it’s important to resolve this biological paradox. Understanding biodiversity is paradoxical because early theories would claim that in order for a certain number of species to survive, there would have to be an equal number of resources available; however, this is not the case and as the populations of species increases, the Earth is unable to continue to provide. Known as the “plankton paradox”, this paradox resembles a plankton ecosystem, in which thousands of plankton depends on a few resources, being light, nitrogen, carbon, phosphorus, iron, etc.
Scientists at the Champalimaud Centre for the Unknown, in Lisbon, Portugal, have developed a new mathematical model, using game theory of aggression as a foundation. Andres Laan, one of the authors of the study, mentions that classical models claim that the fittest species will always be able to obtain the one resource that others are competing for. The others will thus fade into extinction due to that lack of resource. However, a “one-to-one” resource-species relationship is not evident in nature. “We started from a theoretical scenario where we had just two ‘species’: hawks and doves,” Laan explains. “Hawks are bloodthirsty and always ready to fight. Doves are pacific and tend to split resources or run away from fights. According to game theory, in the end, neither purely hawks nor purely doves are dominant, but instead the two ‘species’ coexist.” This could also be applied to other relationships of species, and similar to the hawk-dove game, the species would coexist with each other, rather than driving each other to extinction.
In the end, the scientists found that as the number of resources increase, the number for biodiversity also increases exponentially. For example, on one resource, two species can exist, on two resources, four species, on four resources, sixteen species, and so on. This model allows for predictions to be made about maintaining biodiversity. All of these theoretical notions can be the first steps to understanding the direction of many animal populations and general biodiversity in different environments.