Transcript Symbiosis

Interactions with the
Environment

Limiting Factors
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Scarce resources affect population growth
Example: The number of bugs living in the
rainforest will affect the growth of the frog
population
Carrying Capacity
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Largest population an environment can support
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Limited by the amount of food, water, shelter, and other
factors required by the species.
Interaction between
Organisms
 There are 4 interactions
 Competition
 Individuals or groups try to use the same
resources (food, water, shelter, sunlight)
 The more one uses of the resources, the
less the other can use
 Example: Rabbits in your
backyard are competing
for the same amount of
clover and grass
Predator and Prey
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Many interactions occur between
predators and prey
1. Predator Adaptations
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Predators need a wide variety of methods and
abilities to catch prey (move quickly, ambush)
2. Prey Adaptations
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Prey need a wide variety of methods and
abilities to avoid being caught and eaten by
predators. (Run and hide, stay in groups,
camouflage, spray poison)
A. Camouflage
 Natural color of animal blends with
surroundings
 Mimic materials in surroundings,
becoming hard
to see.
B. Defensive Chemical
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Predators sprayed with
irritating chemicals from
skunk or bombardier
beetle.
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Predators injected with powerful acids from
bees, ants, and wasps.
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Predators eat skin containing deadly toxins
from arrow frog or hooded pitohui.
Warning Coloration
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Animals with defensive chemicals warn
predators to look elsewhere for food
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Predators avoid prey whose color and
patterns are associated with pain, illness,
and unpleasant experiences
Symbiosis
Symbiosis
 Species who have a very close
interaction with other species
 Close long term association between
two or more species
 Individuals can be harmed, unaffected,
or helped by relationship
1. Mutualism
 Both organisms benefit from relationship
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Bacteria in your intestine gets food from you
and breaks down food for you
2. Commensalism
 One organism benefits and the other
organism is unaffected
Example: Frogs get
shelter and water from
the vermiliad. Vermiliad
is not affected.
3. Parasitism
 One benefits (parasite) and the other is
harmed (host)
 Example: Ticks on dogs