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Published byTamsyn Elisabeth Rose Modified over 9 years ago
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BIOTIC FACTORS AFFECTING POPULATIONS
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I. THE CONCEPT OF DENSITY DEPENDENCE I. THE CONCEPT OF DENSITY DEPENDENCE u Vital rates change as density changes
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I. THE CONCEPT OF DENSITY DEPENDENCE I. THE CONCEPT OF DENSITY DEPENDENCE u Vital rates change as density changes u Evidence for density dependence
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II. LIMITATION AND REGULATION OF POPULATIONS u Limiting factors u any environmental factor quantifiably affecting population growth u biotic and abiotic
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II. LIMITATION AND REGULATION OF POPULATIONS u Limiting factors u Regulating factors u density-dependent factors (depress growth as N increases) u biotic (competition, predation, disease)
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III. LOGISTIC MODEL OF POPULATION GROWTH III. LOGISTIC MODEL OF POPULATION GROWTH
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IV. INTRASPECIFIC COMPETITION IV. INTRASPECIFIC COMPETITION A. Food As a Proximate Cause
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IV. INTRASPECIFIC COMPETITION u Food supplementation experiments u home-range size declined u home-range overlap increased u the breeding season was lengthened u litter sizes increased in poor habitat u population density increased 2-3 fold
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IV. INTRASPECIFIC COMPETITION A. Food As a Proximate Cause Limitation? Yes Regulation? No
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IV. INTRASPECIFIC COMPETITION A. Food As a Proximate Cause
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IV. INTRASPECIFIC COMPETITION A. Food As a Proximate Cause
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IV. INTRASPECIFIC COMPETITION A. Food As a Proximate Cause B. Space As a Proximate Cause
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IV. INTRASPECIFIC COMPETITION A. Food As a Proximate Cause B. Space As a Proximate Cause C. Effects of Competition on Vital Rates u Dispersal rate…
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IV. INTRASPECIFIC COMPETITION u Dispersal rate u lower survival rate of dispersers u nondispersers survive better
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IV. INTRASPECIFIC COMPETITION C. Effects of Competition on Vital Rates u Survival rate: Juvenile mammals u snowshoe hares
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IV. INTRASPECIFIC COMPETITION C. Effects of Competition on Vital Rates u Survival rate: Juvenile mammals
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IV. INTRASPECIFIC COMPETITION u Survival rate: A dult mammals
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IV. INTRASPECIFIC COMPETITION IV. INTRASPECIFIC COMPETITION u Fertility rate (Inversity)
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