Unit 3 a ch 8 s2 how species interact with each other
1. Ch8, Section 2: How Species Interact with
Each Other
Standards: SEV3e, SEV5a, b
2. What is a specie’s niche?
Niche- role a species has
within an ecosystem.
Includes:
Species physical home
Factors needed for survival
Interactions with other
organisms
Ex: Bison are grazers & help
control tree sapling
populations as well as fertilize
soil for grass
Ex: Fungi & bacteria are
decomposers, recycling
nutrients to soil.
3. What is a specie’s habitat?
Place where a species
lives
An organism performs
its niche in its habitat.
4. How do species interact with
each other?
1.
2.
3.
4.
5.
Competition
Predation
Parasitism
Mutualism
Commensalism
5. 1. Competition
Relationship where individuals
or populations share limited
resources
Both species are harmed
-/- interaction
Intraspecific competitionwithin the same species.
Ex: caterpillars of the same
species eating the same leaf.
Interspecific competitionbetween different species
When members of different
species compete we say their
niches have overlapped.
Ex: hyenas compete for kill
with lions
6. 1. Competition
Indirect competitioncompete even though
they do not come in
contact with each other.
Ex: An insect that eats a
leaf during the day
competes indirectly with
an insect that eats the
same leaf at night.
Ex: Plants compete for
pollinators; humans
compete with insects for
food crop.
7. 1. Competition
Adaptations to
competition When 2 species compete
for a resource, usually
only one will win.
The other species must
move to find new
resources.
This is called competitive
exclusion.
8. 1. Competition
Competitive exclusion can lead
to niche restriction.
These species share the same
niche & habitat but use a smaller
portion of it.
Ex: Two barnacle species
Chthamalus & Balanus
share the same intertidal zone
of a rocky shore line
Chthamalus lives at higher tide
line (realized niche)
When Balanus is
removed, Chthamalus will
move further down into the
original Balanus habitat.
(fundamental niche)
Realized niche- where the species
actually lives
Fundamental niche- where the species
could live if given a chance.
9. 2. Predation
Predator feeds on prey
Predator benefits, prey is
harmed
+/- interaction
Some predators are very
specific about what they eat
Canadian lynx only eat
snowshoe hares
Creates predator/prey
oscillations
Most predators generally eat
any prey they can capture
Not all predators are
carnivores
10. 2. Predation
Animals adapted to avoid
predation:
Camouflage- hard to see;
blend in
Ex: some caterpillars; lizards
Warning coloration- alert
potential predator that they
are dangerous
Ex: poison dart frogs
Mimicry- look like something
more dangerous even if it isn’t
Ex: some flies have same
coloration as bees
Protective coverings- too hard
for predator to eat.
Ex: porcupine, turtle, cactus
11. 3. Parasitism
Parasite lives and feeds on host
organism.
Parasite benefits, host is harmed
+/- interaction
Parasites are different from
predators because they do not
usually kill their host (what else
would they eat if they killed
their host?)
Parasite can weaken host &
make them more susceptible to
disease.
Ex:
ticks, leeches, mistletoe, fleas
12. 4. Mutualism
Each species benefits
from the relationship
+/+ interaction
Some species couldn’t
live without each other
Ex: bacteria in your
intestine; acacia tree &
ants; insects & flowers
13. 5. Commensalism
One species is benefited
and the other is neither
harmed nor helped.
+/0 interaction
Ex: orchids in trees;
clownfish & anemones;
remoras and sharks
14. What is Symbiosis
Relationship where two
species live in close
association
Often one species
benefits.
Which of the five
species interactions are
considered symbiosis?
15. What is Coevolution?
When species have
such close relationships
they often coevolve.
These two species
would be less likely to
survive if one were
missing.
Ex: bee orchids
Hinweis der Redaktion
When P. aurelia and P. caudatum are grown separately they grow exponentially until their populations level out.When these paramecia are put in the same dish the P. aurelia outcompetes the P. caudatum and P. caudatum dies off. P. caudatum was not able to compete with the other paramecium species for the food resources.
Some caterpillars look like bird poopLizard camouflagePoison dart frogBee fly has same color patter as bees but no stingerMonarch butterfly has bad taste. Viceroy butterfly does not but because they look like monarch butterflies they are left alone.
Caterpillar has been parasitized by a parasitic wasp. The parasitic wasp laid eggs on the caterpillars back. These eggs will hatch into larva that will burrow inside caterpillar and eat caterpillar from inside out.Mistletoe grows inside the tree branch stealing its nutrients/water
Bacteria help you break down nutrients; you provide home/nutrients for bacteriaAcacia tree provides ants with home & sugary nectar glands; ants protect tree from herbivores
Orchids use tree to get to sunlight but do not get anything from the tree.Clownfish live in anemones but don’t help/hurt the anemone in any wayRemoras attach to sharks with suction cup like head. When shark eats they detach and eat scraps of food. Don’t hurt shark or help it.
Parasitism, mutualism, commensalism (predation probably not considered symbiosis b/c two species don’t really live in close association.
This bee orchid has a dark region with yellow spots that resemble the abdomen of a female bee. Male bees will try to copulate with the orchid and in the process will pollinate the orchids.