Post on 01-Jan-2016
Biological Communities• Community
– “all the living organisms and the environment they live in”
– Communities are characterized by:• Species diversity
–“Number of different species present”• Species composition
–“Number of individuals in each species”• Primary productivity
–“Amount of energy produced”
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Functional Roles of Living Organisms
• Organisms are categorized by what they eat:
• Primary consumers• Secondary consumers• Tertiary consumers
Roles Outside the Trophic Pyramid
• Scavengers
• Detritivores– Feed off detritus
• There are 2 types of detritivores– Detritus feeders
– Decomposers
Ecological Niche
• Niche: “A species’ way of life or functional role in the ecosystem”
• There are two types of ‘niches’– Fundamental niche– Realized niche
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Niches - Competition
• Because of competition, realized niches are much smaller than fundamental niches.
• 2 Types of competition:– Intraspecific competition– Interspecific competition
• Exploitative competition
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• Resource partitioning
– Morphological
– Temporal
– Spatial
Morphological Temporal Spatial
Ways to Avoid Competition
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Moth
Flower Fly
Wasp
Honey bee
BatesIan
Mimicry
Species Interactions• Commensalism: “One species benefits. The other is neither hurt nor helped”
• Mutualism: “both species benefit”
• Parasitism: “one species benefits at the expense of another”
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