A sea anemone makes an ideal home for a clownfish. Its poisonous tentacles provide protection from predators and a clownfish makes its meals from the anemone’s leftovers A clownfish can help an anemone catch its prey by luring other fish toward over so that the anemone can catch them. Clownfish also eat any dead tentacles keeping the anemone and the area around it clean. "
Orchids form their base of attachment on the branches of trees, and benefit by getting adequate sunlight and nutrition that flows down the branches. The orchids do not grow to a large size, and thus the host tree is not harmed in any way.
The remora forms a special relationship with sharks and other sea organisms like whales and turtles. It has special suckers attached to its fins. It attaches itself to the bodies of sharks, and uses the shark for transportation as well as protection from its predators. It also eats up the scraps of food that are left over when the shark eats its prey.
A territory is an area defended by one or more individuals against other individuals. The territory is of value not only for the space but also for the shelter, food, or breeding sites it contains.
A pack is an extended family group comprised of a the breeding, or “alpha” male and female pair and some of their subordinate offspring and current pups from one or more years.
The parent wolves are the leaders of the pack - the alpha male and alpha female.
The alpha male and female are the oldest members of the pack and the ones with the most experience in hunting, defending territory, and other important activities. and normally are the first to eat at a kill.
The pair’s offspring normally disperse into adjacent or available territories at 2 to 3 years of age.
ENVI 6 community ecology FINAL
The division of ecology that
deals with the study of the
interactions among species and
interactions with the abiotic
Composed of all population of
a given area
A group of populations
interacting with one another
within the same environment.
RELATIONSHIP AMONG ORGANISMS
two entire different organisms live in close association that
benefits at least one of them.
Kinds of Symbiotic Relationship
Both organisms are
benefited and obligatory
Lichens consists of algae and
Algae produce food.
Fungi provide water and
Both organisms are benefited
but not obligatory
Double positive interaction
A sea anemone makes an ideal
home for a clownfish.
A clownfish can help an anemone
catch its prey by luring other fish
toward over so that the anemone
can catch them.
One organism benefits while the other is neither benefited nor
Positive-neutral interaction (+,0)
One organism (parasite) benefits and the other (host) is harmed
Positive-negative interaction (+,-)
One organism is
inhabited or destroyed
and the other is not
Algal bloom can lead to the
death of fishes, however
the algae do not benefit
from these deaths.
benefits while prey
species is harmed
One organism benefits
at the expense of
Both organisms are affected
Organisms struggle with each other to obtain limited resources
Can be interspecific or intraspecific
Negative-negative interaction (-,-)
Gause’s Principle (Interspecific Competition)
If two populations of organisms occupy the same ecological niche,
one of the populations will be eliminated.
species fight for
resources within an
members of the
same species fight
for resources within
These wolves are
competing for food
and for social
TYPES OF TWO-SPECIES INTERACTION
INTERACTION SPECIES A SPECIES B DESCRIPTION
Mutualism + + Both benefited and obligatory
Protocooperation + + Both benefited and not obligatory
Commensalism + O Species A is benefited while species B is
Parasitism + – Species A is benefited while species B is harmed
Amensalism – O Species A is harmed while species B is unaffected
– – Both are affected
Predation + – Species A feeds on species B.
It is a gradual process of change and replacement of the types
of species in a community
In nature, the process of ecological succession may take
hundreds or thousands of years.
Each new community that arises often makes it harder for the
previous community to survive.
It is a type of succession that occurs on a surface where no
ecosystem existed before.
Primary succession can occur on rocks, cliffs, and sand dunes.
Primary succession is much slower than secondary succession
because primary succession begins where there is no soil.
It can take several hundred to several thousand years to produce
fertile soil naturally.
It is the more common type of succession, occurs on a surface
where an ecosystem has previously existed
Secondary succession occurs in ecosystems that have been
disturbed or disrupted by humans, animals, or by natural
processes such as storms, floods, earthquakes, and volcanoes.
The first organisms to colonize any newly available area and begin
the process of ecological succession.
Over time, pioneer species will make the new area habitable for
It is a final stage and stable community.
Even though a climax community continues to change in small
ways, this type of community may remain the same through time if
it is not disturbed.
Lichens (left) are colonizing a boulder. Over a long period of time, lichens can break down rock into
Plants that grow through cracks in city sidewalks (right) can also be described as pioneers of primary
When Mount St. Helens erupted
in 1980, much of the forest
around the volcano was
The photo above was taken 12
years after the eruption of Mount
St. Helens and shows evidence of
This fire fighter is helping
maintain a controlled fire in South
Some fires are set on purpose by
fire officials to bring nutrients to
soil from burned vegetation.
These young lodge pole pine
trees have started growing after a
devastating forest fire.
succession is old-
which occurs when