community interactions -...
TRANSCRIPT
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Community Interactions
• What is a community?
Community Interactions
• Competition
• Predation
• Symbiosis– Mutualism– Commensalism– Parasitism
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Competition
• Competitive Exclusion—4 results:
– G.F. Gause (P. caudatum & P. aurelia)
– Connell (barnacles) – niche partitioning
– Resource partitioning – ex. warblers
– Character displacement -- evolutionary
Predation—Animal Adaptations
• Mimicry
– Batesian mimicry — Harmless species imitates a dangerous species
– Mullerian mimicry — two or more dangerous species look similar
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Predation—Plant Adaptations
• Physical Defenses– Spines
– Sticky hairs
– Tough leaves
• Chemical Defenses– Poisonous
– Irritating
– Bad-tasting
Secondary compounds
Symbiosis
• Mutualism—both organisms benefit
• Commensalism—one organism benefits & the other neither benefits nor is harmed
• Parasitism—one organism benefits & the other is harmed (host)
– 2 types of parasites
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Mutualism
Commensalism
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Parasitism
Ectoparasite Endoparasite
Ecological Succession
• Primary Succession (No soil present)– No soil exists (newly exposed areas)– Occurs after volcanic activity– Begins with pioneer species (lichens)
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Ecological Succession
• Secondary Succession (Soil present)– Occurs after the existing community has been disturbed w/o removing soil
– Occurs after wildfires, plowing land
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