Download 3.4 Community Interactions

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Anchor: BIO.B.4.2 Describe interactions &
relationships in an ecosystem
◦ BIO.4.2.2: Describe biotic interactions in an
ecosystem
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Organisms interact with each other when
share same habitat or niche
Types of interactions:
◦ Competition
◦ Predator/prey
◦ Symbiosis: two organisms in close, constant contact
 Commensalism
 Mutualism
 Parasitism
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Community Interactions
◦ Competition: organisms attempt to use a resource at
the same time in the same place
 Resource could be mate, food, territory, etc.
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Predation: one organism (predator)
captures and kills another organism
(prey)
◦ Ex: lion hunts and kills wildebeest
http://dsc.discovery.com/tv-shows/life/videos/komododragons-hunt-buffalo.htm
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Symbiosis: relationship in which two species live
closely together
◦ Mutualism: both species benefit from the
relationship
 Ex: Flowers depend on bees to pollinate them
 Flowers  reproduce
 Bees  get food
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Symbiosis
◦ Mutualism:
 Ex: Birds on back of buffalo
 Birds food
 Buffalo get cleaned/protection from parasites
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Symbiosis
◦ Commensalism: one species benefits; one is
unaffected
 Ex: Barnacles attaching to whale
 Barnacle  filters water to get food
 Whale  unaffected
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Symbiosis
◦ Commensalism:
 Ex: Orchids growing up
trees in Rain Forest
 Orchids  more sunlight
 Tree  unaffected
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Symbiosis
◦ Parasitism: one species (parasite) feeds on but
doesn’t kill another (host)
 Ex: tick (parasite) on a deer (host)
 Ex: tapeworms (parasite) in animals intestines (host)