Intraspecific variation promotes coexistence under competition for essential resources

Intraspecific variation may be key to coexistence in diverse communities, with some even suggesting it is necessary for large numbers of competitors coexist. However, theory provides little support this argument, instead finding that intraspecific generally makes more difficult species Here we present a model competition where two compete essential resources and individuals within populations vary their ability take up different resources. We found range cases expands the conditions under which can occur, mechanism allows ecologically neutral evolutionary stable strategy (ESS) become stable. demonstrate result relies on nonlinearity function describes how traits map onto ecological function. A sigmoid mapping order because an unbounded trait while maintaining biologically realistic boundaries uptake rates, differs from other kinds nonlinearity, only unidirectionally increase or decrease The function’s spreads unevenly along growth function, positive contributions compensate loses others, akin source-sink dynamics, leading coexistence. In way, able amplify niche differences, thereby strengthening discuss empirical systems beyond piecewise functions (i.e., thresholds) are important.