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K selection vs. r selection

K selection

Also K-selection

Ecology.

selection occurring when a population is at or near the carrying capacity of the environment, which is usually stable: tends to favor individuals that successfully compete for resources and produce few, slowly developing young, and results in a stable population of long-lived individuals.

r selection

Also r-selection

Ecology.

selection occurring when a population is far below the carrying capacity of an unstable environment: tends to favor individuals that reproduce early, quickly, and in large numbers so as to make use of ephemeral resources and ensure that at least some offspring survive.