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Ecology is the
interactions between
various organisms
and their
environments.
This includes
interactions between
living and non living
factors.
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The place where an
organism lives and
that provides the
things the organism
needs is called it’s
habitat.
Habitats provide
food, water, shelter,
and other things
needed to grow and
reproduce.
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Biotic Factors are the
living parts of an
ecosystem. They
include grass, plants,
seeds, and other
organisms.
Abiotic Factors are the
nonliving parts of an
ecosystem. They
include things such as
water, sunlight, oxygen,
soil, and temperature.
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Species: A group of
organisms that are
physically similar and
can reproduce with
each other to produce
fertile offspring.
Population: All the
members of one
species in a particular
area.
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Community: All the
different populations
that live together in
an area.
Ecosystem: The
community and
abiotic factors in a
specific area.
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Population can
change in size when
new members enter
the population or
when members leave
the population.
This can occur due to
births, deaths,
immigration, and
emigration.
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Populations can often
change due to limiting
factors.
A limiting factor is an
environmental factor
that prevents a
population from
increasing.
Some limiting factors
for populations are
food, space, and
weather conditions.
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The changes that make
organisms better suited to
their environments
develop through a process
called Natural Selection.
Individuals in a
population have different
characteristics. Those
individuals whose
characteristics are best
suited for their
environment tend to
survive and produce
offspring.
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Over many generations
individuals with those
characteristics continue to
reproduce. Individuals
that are poorly suited to
the environment are less
likely to survive and
reproduce.
This process results in
adaptations, the behaviors
and physical
characteristics of species
allow them to successfully
live in their environments.
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Every organisms has a
variety of adaptations
that are suited to its
specific living
conditions.
The organisms
particular roles or
how it makes its
living, is called its
niche.
Frozen Frogs
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Back around 1850 in
England there existed
two different types of
moths that came in
light and dark forms.
Pollution from the
Industrial Revolution
darkened the tree
trunks where the
moths inhabited.
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The lighter moths
which used to be well
camouflaged were now
easily seen by birds that
would eat them.
The dark colored moths
now had a characteristic
which helped them
survive in their
environment because
they could not be seen
on the dark tree trunks.
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It’s important to
realize that an
adaptation is not
always beneficial in
every environment.
Can you think of an
environment where it
would not be
beneficial to be a dark
colored moth?
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The Galapagos Islands
are a group of islands
located off the coast of
South America.
There are different
dominant bird species
on almost every island.
Why?
The food available on
each island differs in
size. The bird with the
beak best suited to eat
the food usually
survives.
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Some beaks are
advantageous to have
on certain islands but
not others.
Organisms that are
able to eat usually are
able to grow up and
reproduce.
This is Survival of the
Fittest.
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Dairy Farmers
sometimes only breed
the cows that produce
the best milk. Over
time the milk product
is better because only
the best cows are
reproducing.
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Some insects use mimicry to
make themselves look like a
dangerous creature, even
though they are really not.
Example: The picture to the
right is not a wasp. It is
actually a moth. Some
people call it a hornet moth
because of it’s appearance.
Animals such as this that are
naturally different can use
this as an advantage and
survive. Insects can not
decide when to use mimicry
but if they naturally have
traits that help them survive
they will pass them on to
their offspring.
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The structure of an
organisms organs can
often help it survive
in a specific
environment.
Birds have hollow
bones which allow
them to fly in air.
Dense root structures
allow plants to grow
in compact arid soil.
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All of these characteristics
we have discussed are
inherited. That means
they are passed on from
parent to offspring.
Acquired characteristics
are just the opposite.
They are acquired during
the life of the organism
and not passed on to their
offspring. Just because
your Dad was really good
at football doesn’t mean
you will be. He acquired
that trait.
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Examples of Inherited
Characteristics could
be: Eye Color, Hair
Color, Height, Color
Blindness, Diseases,
Face Shape, being
Bald, etc.
Examples of Acquired
Characteristics could
be: Sports Skills,
Education, Muscle
Mass, etc.
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There are 3 main
types of interactions
among organisms.
They are competition,
predation, and
symbiosis.
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Different species can
share the same habitat.
Different species can
also share similar food
requirements.
For example Lions and
Hyenas are both flesh
eaters that live in the
Serengeti. They must
constantly compete for
limited resources.
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An interaction in
which one organism
kills and eats another
is called predation.
The organism that
does the killing is the
predator. The one
that is killed is the
prey.
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Predators have
adaptations that help
them catch and kill
their prey.
For example a cheetah
can run very fast for a
short time, enabling it
to catch its prey.
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Remember the
Peppered Moth. That
is an example of prey
adaptations.
Other examples are
protective coverings
such as the quills a
porcupine has.
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As Predator
Populations increase
they overuse their
resources and prey sizes
decrease.
Because there is less
prey this causes
predator sizes to
eventually decrease.
Because predator sizes
go down this causes
prey sizes to increase.
As you can see this can
be an endless cycle!
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Symbiosis is a close
relationship between
two species that
benefits at least one of
the species.
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A relationship in which
both species benefit is
called mutualism.
At this very moment
you are participating in
a mutualistic
relationship. Bacteria
called Escherichia coli
in your stomach. They
help you digest foods
that mammals can not
normally digest and
you give them a place to
live.
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Commensalism is a
relationship in which
one species benefits and
the other species is
neither helped nor
harmed.
Least common type of
symbiosis
Red Tailed Hawk can
build it’s nest in a
cactus. The hawk gets
shelter but the cactus
gets no benefit.
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Parasitism involves one
organism living on or
inside another organism
and harming it.
Common parasites are
ticks and leeches. These
parasites have adaptations
that enable them to attach
to their host and feed on
its blood.
Unlike a predator, a
parasite does not usually
kill the organism it feeds
on.
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An organisms energy
role in an ecosystem
may be that of a
producer, consumer,
or decomposer.
Most energy is
introduced through
the sun into the
ecosystem.
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Energy first enters most
ecosystems as sunlight.
Some organisms such as
plants, algae, and some
bacteria, are able to
capture the energy of
sunlight and store it as
food energy.
An organism that can
make its own food is a
producer. Producers are
the source of all the food
in an ecosystem.
Photosynthesis: Using
Sunlight + CO2 + H20 =
O2 + Sugar (Glucose)
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Some Archaebacteria
can produce food
from gas and
hydrogen sulfide.
They are often found
in deep sea vents,
geysers, or under
ground.
Archaebacteria are
now part of the
Kingdom Monera.
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Consumers are organisms
that obtain energy by
feeding on other organisms.
Consumers are classified by
what they eat. (Cattle, Deer)
Consumers that eat only
plants are called herbivores.
Consumers that eat only
animals are called
carnivores. (Lions, Spiders,
Snakes)
Consumers that eat both
plants and animals are
called omnivores.
(Example: Crows, Goats,
Humans)
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Organisms that break
down wastes and dead
organisms and return the
raw materials to the
environment are called
decomposers. (Bacteria,
Fungi, Mushrooms, Mold)
Without Decomposers
their would be no energy
cycle because they return
materials such as carbon
and nitrogen back to the
soil where plants can use
them)