Download Competition

Community
Interactions
EQ: How do the three types
of symbiosis differ?
Types of Interactions
 Competition
 Predation
 Symbiosis
Mutualism
Commensalism
Parasitism
Competition (-/-)
 Organisms
of the
same or different
species compete
for the same
resource in the
same place at
the same time.
Elk Herd
Bison
Moose
Competition

Intraspecific competition:
Competition among
members of the same
species
Tiger Swallowtail butterfly

Interspecific competition:
Competition between
members of different species
Blue Butterfly
Competitive exclusion principle:
No two species can
occupy exactly the
same niche in exactly
the same habitat at
exactly the same time.
One will always
exclude the other.
Predation (+/-)
Interaction in which one
organism captures and feeds
on another organism

predator
Falcon
prey
Herbivory:
•
Type of predation
•
Interaction in which an
herbivore feeds on
producers.
Ground Squirrel
Predation
Keystone species: a single
species that is vital to the
ecosystem stability.
Ex. Otters/kelp/sea urchins
Predation
Arctic Hare

Rabbit and Coyote
Coyote
rabbit
coyote
Symbiosis
 Any
relationship in which two
species live closely together.
 Mutualism
 Commensalism
 Parasitism
Mutualism (+/+)
 Both
organisms
benefit
Bee on Purple Flower
o
Examples:
o
Flowers and insects
o
Ants and aphids
Ant and Aphid
Mutualism (+/+)
 Lichen
Lichen
 Algae
and
fungus living
together
Commensalism (+/0)
 One
organism
benefits and the
other is neither
helped nor harmed.
Spanish Moss
Commensalism (+/0)
 Whales
& Barnacles
Barnacles on Whale
Commensalism (+/0)
 Epiphytes
“air plants”
Epiphyte in Tree
Epiphyte
Parasitism (+/-)
 One
organism benefits while the
other is harmed
 Examples:
tapeworms inside
mammals; fleas,
ticks, and lice on
mammals
Female Head Lice
Parasitism (+/-)

 Ticks
Before
After
The parasite
obtains all or part
of its nutritional
needs from the
other organism,
the host.
Blacklegged Tick: An adult female
blacklegged tick, engorged after a
blood meal, rests on a leaf.
Black Legged Tick