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Source–sink dynamics is a theoretical model used by ecologists to describe how variation in habitat quality may affect the population growth or decline of organisms.. Since quality is likely to vary among patches of habitat, it is important to consider how a low quality patch might affect a population.
A population ecology concept is r/K selection theory, one of the first predictive models in ecology used to explain life-history evolution. The premise behind the r/K selection model is that natural selection pressures change according to population density. For example, when an island is first colonized, density of individuals is low.
An important concept in population ecology is the r/K selection theory. For example, if an animal has the choice of producing one or a few offspring, or to put a lot of effort or little effort in offspring—these are all examples of trade-offs.
In biomathematics, the Kolmogorov population model, also known as the Kolmogorov equations in population dynamics, is a mathematical framework developed by Soviet mathematician Andrei Kolmogorov in 1936 that generalizes predator-prey interactions and population dynamics. The model was an improvement over earlier predator-prey models, notably ...
Propagule pressure (also termed introduction effort) is a composite measure of the number of individuals of a species released into a region to which they are not native. It incorporates estimates of the absolute number of individuals involved in any one release event (propagule size) and the number of discrete release events (propagule number).
One of the most basic and milestone models of population growth was the logistic model of population growth formulated by Pierre François Verhulst in 1838. The logistic model takes the shape of a sigmoid curve and describes the growth of a population as exponential, followed by a decrease in growth, and bound by a carrying capacity due to ...
Organizational ecology can be usefully compared with evolutionary theories in economics (e.g. Nelson & Winter, 1982). [1] Hannan and Freeman also note the influences of biological ecology and economic evolution on their population ecology model (specifically Elton, 1927; Durkheim, 1947; Hawley, 1950; and Hutchison, 1959). [2]
Consider a population at harvested at a constant harvest level . If the population falls (due to a bad winter or illegal harvest) this will ease density-dependent population regulation and increase yield, moving the population back to , a stable equilibrium. In this case, a negative feedback loop creates stability.