Competitive Exclusion Principle

The competitive exclusion principle, also known as Gause's Law, states that two species competing for identical limiting resources cannot coexist indefinitely in a stable environment — one will outcompete and eliminate the other. The principle is mathematically grounded in the dynamics of competitive resource consumption: when per-capita growth rates depend only on shared resources, the species with the even slightly higher uptake efficiency drives the other to extinction. It was established experimentally by Georgii Gause in the 1930s using mixed cultures of Paramecium, and it remains one of the foundational theorems of community ecology.

Yet the principle is systematically violated in nature, and the violations are not minor exceptions but the rule. The resolution is that stable