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Paraziții metazoanici sunt exemple. Paraziții metazoanici sunt exemple - printreoale.ro

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In predators[ edit ] When predators need to search for their prey, they could search at random, as has been paraziții metazoanici sunt exemple in models such as those made by Lotka in and Volterra in This would imply that they scatter themselves evenly across the environment.

The zoologists M. Hassell and R. May noted that predators and parasites, too, might aggregate themselves where prey was abundant, choosing some response curve: they observed for example that redshanks predatory birds adopted a sigmoid s-shaped response to the density of Corophium amphipod prey per square metre of mudflats.

Determinarea paraziților metazoanici

They noted, too, that several different behaviours of predators or parasites could cause them to aggregate selectively in areas where prey are viermi ce medicament high density: they could be attracted by a volatile paraziții metazoanici sunt exemple liberated by prey or the plants they are feeding on; they could choose to spend more time in areas where they have caught prey, as many predators appear to do; or, predators could follow an individual predator which had located prey, as is seen in feeding terns.

Aggregated distributions of predators where they tend to spend time in areas where prey are concentrated have the effect of stabilising prey populations; when the time to travel between such concentrated areas is high; and when paraziții metazoanici sunt exemple prey populations too are more highly clumped.

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It is widespread, too, in trophically transmitted parasites of animals. The observed pattern is that most individual hosts are free or almost free of parasites, while a minority carry a large number of parasites. Log-transformation of data before the application of parametric test, or the use of non-parametric statistics is recommended by several authors, but this can give rise to further problems, so quantitative parasitology is based on more advanced biostatistical methods.

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