Download Predation Competition Symbiotic

Relationships in Nature
Predation
Competition
Symbiotic
Predation
• An interaction in
which one
organism kills
another for food
• Ex: green tree
python eats a
mouse
Competition
• The struggle
between organisms
to survive as they
attempt to use the
same limited
resources
• Some species will
adapt so that they
may coexist
Why can’t two species occupy the
same niche?
(Think back to 7th gradeCarrying Capacity & Limiting
Factors)
Symbiotic Relationships
• Any two different species of organisms that
live together in a close relationship
• A permanent association
• One member of the relationship always
benefits… the other may also benefit, or it
maybe be harmed or unaffected
• There are three forms of symbiotic
relationships:
– mutualism
– commensalism
– parasitism
Mutualism
• A relationship in which both species
benefit
• Examples:
– Bee & Flower
– Zebra & Oxpecker
– Lichen & Algae
Lichen & Algae
• The lichen furnishes the
algae with water, prevents
overexposure to sunlight,
and provides nutrients.
In return, the algae
provides food to the
lichen, especially in harsh
conditions such as:
desert, tundra, high
mountains, etc.
-Lichen: stringy stuff
-Algae: (not seen)- cellular level
Zebra & Oxpecker
• The zebra benefits by
having the oxpecker
eat the ticks &
parasites off the
zebra. The oxpecker
benefits by receiving
nutrition from the
ticks & parasites (and
the oxpecker does not
waste energy
searching for food)
• The bee benefits
by feeding off
the nectar in the
flower. The
flower benefits
by being
pollinated by
the bee.
• (When the bee
visits one
flower, pollen is
deposited on
it’s body, then
the pollen is
transferred to
another flower
by the bee)
Bee & Flower
Commensalism
• A relationship in which one species
benefits. The other species does not
benefit nor is it harmed.
• Examples:
– Whale & Barnacles
– Cattle Egret & Livestock
– Clown Fish & Sea Anemone
Whale & Barnacles
• Barnacles attach themselves to the skin of
whales. The barnacles “hitch a ride” on the
whale. The whale is not harmed, nor does it
benefit from this relationship.
Clown Fish & Sea Anemone
• A sea anemone has a
poison on it’s
tentacles that are
harmful to most fish.
The clown fish has
developed an
immunity to the
poison and can use
the anemone as
protection. The sea
anemone does not
benefit, nor is it
harmed from this
relationship.
Cattle Egret & Livestock
• Cattle Egrets live in
many pastures
occupied by
livestock. When the
livestock move
about the pasture,
they kick up bugs
and insects. The
cattle egrets feed on
these bugs. The
livestock does not
necessarily benefit
from this
relationship, nor are
they harmed.
Video Link
Parasitism
• A relationship in which one species
benefits and the other is harmed, but
usually NOT killed.
• Examples:
– Ticks & Dog (or cat, monkey, rabbit,
guinea pig, etc)
– Mistletoe & Tree
– Hookworm & Human Intestine
Tick & Dog
(or other mammals)
• The tick takes blood from it’s host (the
mammal). The dog (or mammal) can contract
diseases from the tick and can be deprived of a
normal blood supply.
Mistletoe & Tree
• Mistletoe is a plant that grows
on other plants/trees. The
mistletoe takes water and
nutrients from the host tree
sap for growth and
development. The host tree is
not immediately killed, but can
be weakened and will become
susceptive to breakage, rotting,
and fungi
Hookworm & Human Intestine
• The hookworm feeds on the nutrients in
the intestines. The human is harmed
because the hookworm takes away
important nutrients.
How are predation and
parasitic relationships
different?