Individual Variation and Competitor Coexistence: A Model

Abstract

A simple model of interspecific competition is described, based on the Lotka-Volterra model in difference equation form but incorporating individual variation in competitive ability. Such variation allows the coexistence of competitors where otherwise the superior competitor would rapidly drive the inferior one to extinction. Variation in interspecific competitive ability is especially important; particularly that which affects the response of the poorer competitor to the superior competitor. The level of variation required is realistic for natural populations. Key-words: Competition, coexistence, individual variation