concept

Competitive exclusion principle

The rule that two species cannot occupy the same niche in the same place indefinitely - if they overlap completely in food, timing and method, one will be slightly more efficient and over generations drive the other out entirely. The biologist Georgii Gause demonstrated it with two species of pond microbe: grown separately both thrived, grown together on one food source one always wiped the other out. Its corollary is the engine that drives niche partitioning.