Practice question

The keyed exception is “Density-dependence varies randomly.” In the context of which assumption is not part of lotka–volterra model, that statement differs from the governing ecological pattern and must be evaluated against the mechanism rather than accepted from wording alone. Evidence should connect encounter rates or resource use to survival, growth, or reproduction. The ecological label follows that causal effect rather than superficial proximity between organisms. The remaining alternatives—“Species grow logistically”, “Coefficients are constant”, “Environment is constant”—refer to different states, processes, or scales and therefore do not express the same causal relationship. Species interactions are classified by their net effects on the fitness of each participant, but those effects can change with density, resource supply, life stage, and environmental stress. Competition reduces access to shared limiting factors, whereas predation and parasitism transfer resources from victim to consumer. The cited framing is therefore most useful when treated as a conditional biological claim, with assumptions about scale and environmental context kept explicit.