Community
Interactions
Competition
Predation
Symbiosis
Competition
 Organisms
of the
same or different
species attempt
to use the same
ecological
resource (food,
water, space) in
the same place
at the same time
Competition
 Two
organisms want
the same thing
 Two
different butterfly
species feeding on the
same flowers
Predation
predator
 Interaction
in which
one organism
prey
captures and
feeds on another
organism
Predation
 Grizzlies
prey
upon
salmon
Predation

Rabbit and Coyote
rabbit
coyote
Ultimate Predator?
 Why
is man
sometimes called the
“Ultimate Predator”?
Symbiosis
 Any
relationship in which two
species live closely together is
called symbiosis (“living together”)
 Mutualism
 Commensalism
 Parasitism
Mutualism
 Both
organisms
benefit
Examples:
 Flowers and insects
 Ants and aphids
ants feed off the excrement
(honeydew) of aphids, and ants protect
aphids
Mutualism
 Lichen
 Algae
and
fungus living
together
Commensalism
 One
member of the
association benefits
and the other is
neither helped nor
harmed.
 Examples:
Spanish moss
Commensalism
 Whales
&
Barnacles
Barnacles are "filter feeders“.
Many filter feeders compete for
space on the ocean floor.
Barnacles avoid this
competition by attaching
themselves to whales.
Commensalism
 Epiphytes
“air plants”
Biology, Prentice Hall
Parasitism
 One
benefits; one harmed
 Examples:
tapeworms inside
mammals; fleas,
ticks, and lice on
mammals
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.
Parasitism
Mistletoe
More than just a “kissing catalyst”
Works Cited




Whale barnacles - Christopher M. Callahan,
Humboldt State University
http://www.humboldt.edu/~cmc43/ectoparasites.html
Barnacles on Whale – Baja Jones Adventure Travel
http://www.greywhale.com/photo.htm
Whale lice – Genny Anderson, Marine Science,
Santa Barbara City College
http://www.biosbcc.net/ocean/marinesci/05nekton/G
Wsouth.htm
Grizzly Bear – Mineral Management courtesy of
GeekPhilosopher.com
http://geekphilosopher.com/bkg/anGrizzlyBearFish.ht
m
Works Cited



Artic Hare – U.S. Fish & Wildlife courtesy of
GeekPhilosopher.com
http://geekphilosopher.com/bkg/anArcticHare.htm
Coyote – National Park Service courtesy of
GeekPhilosopher.com
http://geekphilosopher.com/bkg/anCoyote.htm
Ground Squirrel – U.S. Fish & Wildlife courtesy of
GeekPhilosopher.com
http://geekphilosopher.com/bkg/anGroundSquirell.ht
m
Works Cited



Falcon – Bureau of Land Management courtesy of
GeekPhilosopher.com
http://geekphilosopher.com/bkg/birdFalcon.htm
Tiger Swallowtail Butterfly - Bureau of Land
Management courtesy of GeekPhilosopher.com
http://geekphilosopher.com/bkg/butterflyTigerSwallow
tail.htm
Karner Blue Butterfly - U.S. Fish & Wildlife
courtesy of GeekPhilosopher.com
http://geekphilosopher.com/bkg/butterflyKarnerBlue.h
tm
Works Cited




Elk Herd – Bureau of Land Management courtesy
of GeekPhilosopher.com
http://geekphilosopher.com/bkg/anElkHerd.htm
Moose - EPA courtesy of GeekPhilosopher.com
http://geekphilosopher.com/bkg/anMoose.htm
Bison - USDA courtesy of GeekPhilosopher.com
http://geekphilosopher.com/bkg/anBuffalo4.htm
Bee on Purple Flower – BigFoto.com
http://www.bigfoto.com/themes/nature/flowers/flowerbee-8j6.jpg
Works Cited



Spanish Moss – J.S. Peterson @ USDA-NRCS
PLANTS Database, USDA-NRCS. 2005. The
PLANTS Database (http://plants.usda.gov).
National Plant Data Center, Baton Rouge, LA
70874-4490 USA
http://plants.usda.gov/cgi_bin/topics.cgi?earl=plant_p
rofile.cgi&symbol=TIUS&photoID=tius_001_ahp.jpg
Black Legged Tick – Scott Bauer, USDA courtesy
of Junglewalk.com.
http://www.junglewalk.com/frames.asp
Mistletoe – US Forest Service
http://www.fs.fed.us/r6/rogue/swofidsc/dmistletoe/dmi
stletoe.html