EVERYDAY SCIENCE

Detailed explanation-1: -In logistic growth, a population’s per capita growth rate gets smaller and smaller as population size approaches a maximum imposed by limited resources in the environment, known as the carrying capacity ( K).

Detailed explanation-2: -According to the logistic growth model, a population first grows exponentially because there are few individuals and plentiful resources. As the population gets larger and approaches the environment’s carrying capacity, resources become more scarce and the growth rate slows.

Detailed explanation-3: -If a population exceeds carrying capacity, the ecosystem may become unsuitable for the species to survive. If the population exceeds the carrying capacity for a long period of time, resources may be completely depleted. Populations may die off if all of the resources are exhausted.

Detailed explanation-4: -Examples of Logistic Growth Examples in wild populations include sheep and harbor seals (Figure 19.6b). In both examples, the population size exceeds the carrying capacity for short periods of time and then falls below the carrying capacity afterwards.