4 public questions tagged with this topic.
Ecological resilience refers to an ecosystem's ability to recover from disturbances while maintaining function and stability.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Adaptations - Morphological Physiological Behavioural
“Stable coexistence” for when both isoclines cross, and interspecific competition < intraspecific, the result is. This relationship follows from the ecological mechanism represented by the terms in the item, not merely from an association between their names. 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 remaining alternatives—“Extinction of one species”, “Unstable equilibrium”, “Chaotic growth”—refer to different states, processes, or scales and therefore do not express the same causal relationship. Coexistence requires stabilizing differences that make each species limit itself more strongly than it limits its competitor, or an equalizing process that keeps fitness differences small. Without such mechanisms, persistent competitive asymmetry tends toward exclusion. This distinction matters because similar surface patterns can arise through different mechanisms, whereas ecological prediction depends on identifying the mechanism that actually changes rates.
Ref: Ecology: Concepts and Applications, Molles, 9th Ed., Ch. 13-14
“Intraspecific competition > interspecific” for which condition leads to stable coexistence of two species. This relationship follows from the ecological mechanism represented by the terms in the item, not merely from an association between their names. Coexistence requires stabilizing differences that make each species limit itself more strongly than it limits its competitor, or an equalizing process that keeps fitness differences small. Without such mechanisms, persistent competitive asymmetry tends toward exclusion. The remaining alternatives—“Interspecific competition > intraspecific”, “Equal competition”, “Zero dispersal”—refer to different states, processes, or scales and therefore do not express the same causal relationship. 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. Field observations could test this account by measuring the proposed driver and the demographic or ecosystem response while controlling plausible confounding factors. This distinction matters because similar surface patterns can arise through different mechanisms, whereas ecological prediction depends on identifying the mechanism that actually changes rates.
Ref: Ecology: Concepts and Applications, Molles, 9th Ed., Ch. 13-14
An energy pyramid is never inverted under consistent boundaries because each trophic level can convert only a fraction of the preceding level’s production into its own production. This makes its shape more robust than a biomass pyramid, which can change with season, lifespan, and turnover. The deeper mechanism is respiratory heat loss plus incomplete consumption and assimilation; “never inverted” describes the outcome rather than the cause. Rate-based energy measurement therefore avoids misleading snapshots of rapidly renewed producers such as phytoplankton. A snapshot may differ seasonally, especially in plankton or annual vegetation, whereas integrated production better represents ecosystem functioning across time. The ten-percent heuristic is useful for prediction but not exact; empirical transfer efficiencies vary with food quality, ectothermy, producer defenses, and detrital routing. Higher trophic levels are often vulnerable because low energy supply produces small populations that are sensitive to habitat fragmentation and environmental variability. Ecological pyramids must be interpreted according to what is measured—individuals, standing dry mass, or energy flux—because these variables need not have the same shape.
Ref: Fundamentals of Ecology, Odum & Barrett, 5th Ed., Ch. 3
