Competitive exclusion – n species cannot coexist on fewer than n limiting resources in a constant and isolated environment – has been a central ecological principle for the past century. Since ...

Under severe conditions in the arctic the physical environment frequently overrides biological competition, allowing essentially random occurrence of plants without distinct associations and with the ...

It is demonstrated that two species of Drosophila competing for limited resources of food and space can coexist. The principle of competitive exclusion, or “Gause's principle”, is thus rejected.