Ace the 2026 Ecology & Ecosystems QBA Test – Dive into Nature's Challenge!

Carrying capacity explains why a population can stay at roughly the same size over time even as births and deaths continue. It’s the environment’s maximum number of individuals it can sustain indefinitely with available resources. When a population reaches this limit, resources become limiting, and the rate at which new individuals are born tends to balance the rate at which individuals die. The result is a stable, constant population size—the equilibrium at the carrying capacity. A plateau describes the observed leveling-off on a graph, but carrying capacity is the term that identifies the underlying limit causing that pattern.