BIOL 422 Lecture Notes - Lecture 13: Phylogeography, Gene Flow, Ring Species
5 May 2020
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Document Summary
Spatial and population patterns that force complex decisions. Does the predator regulate the prey? (density dependence) With compensatory mortality, total predation rate stays the same but causes of death differ. Predators might be feeding on an age class or compromised individuals, but not others. High mortality of one age/sex class, but lower mortality at a later age. Higher mortality, but also higher reproduction (e. g. re-nesting) Removing a predator from a compensatory system will not lead to a prey increase. Taking out one predator will mean other predators, disease, old age, etc. will still kill the s amount of individuals. Additive mortality: each mortality source increases the mortality rate. Common in system with similar mortality across all age/sex classes. Taking out a predator will increase prey population. Depensatory mortality: two or more mortality sources have a more than additive effect on the mortality rate. The presence of one predator allows another predator to kill more effectively.
