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Practice question

Question

When N ≈ K, the growth rate:

Options

Choose one · Correct answer highlighted

Explanation

The damaged symbol in the prompt is evidently intended to state N equals or approaches K. Substituting N = K into dN/dt = rN(1 - N/K) makes the parenthetical term zero, so net growth becomes zero. Births and deaths may continue, but their population-level contributions balance at the equilibrium. The logistic model is a deliberately simplified, density-regulated model. It assumes a constant intrinsic rate and carrying capacity, no time delay, and no age or spatial structure. Its value lies in exposing the feedback mathematically; real populations can oscillate, overshoot, or track a changing K when those assumptions fail. The key idea is the direction of the trade-off or feedback, because that direction determines the population-level outcome. Field evidence should therefore be compared with the model assumptions before extending the conclusion to every species, habitat, or time period. Interpreting the example at the appropriate population scale keeps the causal mechanism distinct from a simple correlation or an absolute rule.