Communities

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Communities
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Communities

• What is a community?
• What does a community include?

• Different populations that live together in the
  same area.
• An animals niche and/or habitat

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Habit vs. Niche

• A habitat is all aspects of the area in which an
  organism lives.
• biotic factors
• abiotic factors
• An ecological niche includes all of the factors
  that a species needs to survive, stay healthy,
  and reproduce.
• food
• abiotic conditions

• What is the difference between a habitat and a
  niche?

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Communities

• The types of interactions that occur within a
  community, both between and within populations,
  can powerfully affect an ecosystem.

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Community Interactions

• What are the 3 major types of interactions within
  a community?

• Competition
• Predation
• Symbiosis

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Community Interactions - Competition

• What is competition?
• What is the result of competition?

• When organisms of the same or different species
  attempt to use the same ecological resource in
  the same place at the same time.
• In nature, competition usually results in a
  winner (who survives) and a loser (who dies)

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Community Interactions - Competition

• What is the competitive
• exclusion principle?

• Competitive exclusion keeps two species from
  occupying the same niche.
• One species is better suited to the niche and the
  other will either be pushed out or become
  extinct.
• The niche will be divided.
• The two species will further diverge.

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Community Interactions - Competition

• Comepetition between the same species
• Ex. Tigers over food
• Competition between 2 or more different species
• Ex. Hyenas and Lions

• What is intraspecific competition?
• What is interspecific competition?

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Community Interactions - Predation

• What is predation?

• When one organism captures and feed on another
  organism.

The predator eats the prey
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Community Interactions - Symbiosis

• What is symbiosis?

• Any relationship in which two species live
  closely together.
• The term literally means living together

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Community Interactions - Symbiosis

• What are the 4 main types of symbiotic
  relationships?

• Mutualism
• Commensalism
• Amensalism
• Parasitism

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Community Interactions - Symbiosis

• What is mutualism?

• When both species benefit.
• /

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• What is commensalism?

• When one member benefits, but the other is
  neither harmed nor helped
• /o

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Community Interactions - Symbiosis

• What is amensalism?

• When one species impedes or restricts the success
  of the other, but remains unaffected
• -/0
• algal blooms can lead to the death of many
  species of fish, however the algae do not benefit
  from the deaths of these individuals.

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Community Interactions - Symbiosis

• What is parasitism?

• When one organism lives on or inside another
  organism and harms it
• /-