Transcript Ecology - yayscienceclass

Ecological
Interactions
“When one tugs at a single
thing in nature, he finds it
attached to the rest of the
world.”
~John Muir, naturalist, Sierra
Club founder
What is a Niche?
• A niche is a species way of
life, or the role the species
plays in its environment.
• It includes: feeding
relationships , reproduction,
habitat and interactions with
other organisms.
What is the Competitive
Exclusion Principle?
• No 2 SPECIES occupy exactly
the SAME niche! Why?
• Competition!!
How do organisms
interact in a community?
• Predation
• Competition
• Symbioses:
– Parasitism
– Mutualism
– Commensalism
What is Predation?
• The predator captures, kills and
consumes another organism, the
prey.
• Predators have evolved
adaptations to increase their
efficiency at capturing prey, ex.
Sharp teeth, camouflage, spider
web
• Prey have also evolved defenses
against predators, ex. Sharp
thorns, Poisons, Mimicry-resemble
a poisonous species
•A decrease in the prey population means
some predators will starve. Fewer predators
mean prey population will increase.
•Increase in prey means more food for
predators. Predator population will increase
until there is not enough food and the cycle
repeats itself.
What is Competition?
• Competition results from a
niche overlap between 2 or
more species.
• Competition for food, shelter,
mates, space or light.
• Only one organism will use the
resources more efficiently
(and win) that will eventually
eliminate the other species.
COMPETITION
Organisms in an ecosystem have to
compete with each other for available
resources. FOOD
http://www.knology.net/~sgoswald/Eating.jpg
http://www.harcourtschool.com/glossary/science/images/gr3/community3.jpg
COMPETITION
Organisms in an ecosystem
have to compete with each
other for available resources:
shelter
http://www.dpiw.tas.gov.au/inter.nsf/Images/LBUN-5K538R/$File/fox_adultandcub.jpg
http://www.gdccc.org/Records/EOY2004/NSEOY.htm
COMPETITION
Organisms in an ecosystem have to
compete with each other for available
resources
mates
http://www.wasatchcomputers.net/gallery/elk_fight.jpg
http://www.biocrawler.com/w/images/thumb/3/34/200px-Peacock_courting_peahen.jpg
COMPETITION
Organisms in an ecosystem have to
compete with each other for available
resources: space/territory
http://www.elise.com/weblog/photos/prairie-dogs.jpg
Prairie dogs - 5 to 35 per acre
Mountain lion- 1 male per 50-300 sq. mi
http://www.rilanationalpark.org/gr.phtml?dir=../../pictures/in_text&img=/65_1180.jpg
COMPETITION
Organisms in an ecosystem have
to compete with each other for
available resources:
LIGHT
http://vilenski.org/science/safari/cellstructure/chloroplasts.html
http://www.csjbacau.ro/gallery/images/Beech%20Tree%20Forest%20in%20Slanic%20Moldova.jpg
What are symbioses?
• Symbiosis= “living
together”
• Close interaction
(relationship) between 2
species living together
–Parasitism
–Mutualism
–Commensalism
What is Parasitism?
• Involves a parasite that feeds
off another organism, the
host.
• Ex. Ticks, fleas, lice, leeches,
tapeworms, malaria parasite,
disease bacteria
• Parasites have evolved
adaptations to exploit their
host more efficiently
PARASITISM
“Good for me - Hurts you”
http://www.dogbreedinfo.com/guineafowltickphotos.htm
Tick feeds on dog’s blood;
Dog has discomfort, can get diseases/infection from bite
PARASITISM
“Good for me - Hurts you”
Tapeworms
absorb food by
living inside
host intestine;
host is harmed
http://www.biology.ucok.edu/AnimalBiology/Platyhelminthes/tapeworms.jpg
PARASITISM
“Good for me - Hurts you”
http://www.geology.wmich.edu/gillespie/g322/Chapters/C16parasitism.whale.gif
Barnacles are crustaceans that attach to the surface of whales
and feed on their skin and fluids; Whale is harmed.
What is Mutualism?
• Mutualism is a cooperative
relationship between 2 species
in which both benefit.
• Neither can survive without
the other.
• Ex.
– Pollinators & Flowers
– Birds & Rhinos
– Clown fish & sea anemones
MUTUALISM
“Good for me - Good for you”
http://www.providence.edu/bio/faculty/adams/LECTUREProvCollegeMutualism.html
Insects transfer pollen
between plants as they
gather nectar for food.
http://www.yksd.com/DistanceEdCourses/YKSDbiology/lessons/SecondQuarterLessons/Chapter5/5-5/images/3-way-mutualism.jpg
MUTUALISM
“Good for me - Good for you”
Birds eat parasites living
on the hides of giraffes
and rhinos while enjoying
protection from predators.
Groomed animals lose their
pests.
http://www.imbt.org/science.htm
http://www.hugheshome.net/jon/africa02/images/rhino_bird_JPG.jpg
MUTUALISM
“Good for me - Good for you”
Clown fish gets protection from
enemies by hiding out in poisonous
sea anemones
Sea anemone
gets
scraps of
leftover
food dropped
by fish
http://www.zahnersatz.com/english/library/symbiosis.jpg
What is Commensalism?
• Commensalism is an
interaction in which one
species benefits and the
other is not affected.
• Ex.
–Hermit crabs & snail
shells
–Pilot fish & sharks
COMMENSALISM
“Good for me - Doesn’t bother you”
http://www.geology.wmich.edu/gillespie/g322/Chapters/C16shark.gif
Pilot fish receive scraps of food dropped by shark;
Shark is neither harmed nor helped
COMMENSALISM
“Good for me - Doesn’t bother you”
http://www.abyssal.com/meeks/images/hermit_crab.jpg
Hermit crabs make homes in shells abandoned
by snails;
Snail is not harmed by crab
How do Organisms interact?
+ means “benefits” - means “harmed” 0 means “no affect”
Predation
+
predator
prey
Competitor 1
Competitor 2
Parasitism
+
parasite
host
Mutualism
+
Organism 1
+
Organism 2
Commensalism
+
Organism 1
0
Organism 2
SYMBIOSES
Competition
ANY QUESTIONS?
Ecological Interactions Clock ?
• Clock ? #5: Create a VISUAL
ILLUSTRATION explaining this information
on p. 25
– Ex. Diagram, flow chart, concept map,
etc.
– Use the WHOLE page
• OR Clock ? #6: WRITE A LETTER/SHORT
STORY explaining this information on p. 25
– Use the WHOLE page