Download Ecology - WHS Biology

Ecology
LEARNING TARGETS
At the end of this lesson you should be able
to say
1. I can identify the difference between
primary and secondary succession.
2. I can determine which organisms are
producers and consumers.
3. I can identify organisms as herbivores,
carnivores, omnivores and
decomposers/detritivores.
4. I can identify the difference between the
symbiotic relationships commensalisms,
parasitism & mutualism.
WHAT IS ECOLOGY?
Ecology- the scientific study of
interactions between organisms and
their environments, focusing on
energy transfer
Ecology is a science of relationships
WHAT DO YOU MEAN BY ENVIRONMENT?
The environment is made
up of two factors:
•
Biotic factors- all living
organisms inhabiting the
Earth
• Abiotic factors- nonliving
parts of the environment
(i.e. temperature, soil,
light, moisture, air
currents)
Biosphere
Biome
Ecosystem
Community
Population
Organism
Organism - any unicellular or
multicellular organism.
•The lowest level of organization
POPULATION
Population-a group of
organisms of one species
living in the same place at
the same time that
interbreed
Community - several interacting
populations that inhabit a common
environment and are interdependent.
Ecosystem - populations in a
community and the abiotic factors
with which they interact (ex. marine,
terrestrial)
Biome – Group of ecosystems with the
same climate and similar communities
(ex. Desert, Tundra & Arctic)
Biosphere –part of the EARTH in
which life exists (including air, land
and water).
•The highest level of organization
Succession (changes in an ecosytem)
Primary succession- change in an environment
where life had not existed before
• Areas such as receding glaciers or new land
created by lava
Succession
Secondary successionchange in an
environment where
life had existed
before
• Areas such as forest
clearings or areas
where a forest fire
occurred
Feeding Relationships
Producer- all
autotrophs (plants),
that trap energy from
the sun
• Bottom of the food
chain
Feeding Relationships
Consumer- all heterotrophs: they
consume food (other organisms)
1.
2.
3.
4.
Herbivores (eats only plants)
Carnivores (eats only meat)
Omnivores (eats both)
Decomposers (absorb nutrients
from dead and decaying plants
& animals)
Feeding Relationships
Herbivores-eat only
plants
Feeding Relationships
Carnivores-eat meat
Feeding Relationships
Omnivores -eat both plants
and animals
Feeding Relationships
Decomposers/Detriti
vores
-obtains nutrients
from dead and
decaying plants and
animals
Ex. Bacteria or Fungi
& Earthworms
Symbiotic Relationships
Symbiosis- two species living together
3 Types of
symbiosis:
1. Commensalism
2. Parasitism
3. Mutualism
Symbiotic Relationships
Commensalismone species benefits
and the other is
neither harmed nor
helped
Ex. Pilot fish and sharks
Commensalism: Pilot fish follows
underneath the shark and eats any
scrap pieces that the shark does not.
Symbiotic Relationships
Commensalismone species benefits
and the other is
neither harmed nor
helped
Ex. polar bears and
cyanobacteria
Commensalism: Cyanobacteria grow on
the fur of the Polar Bear and neither
helps nor harms the bear.
Symbiotic Relationships
Parasitismone species benefits (parasite) and
the other is harmed (host)
• Parasite-Host relationship
Symbiotic Relationships
Parasitism- parasite-host
Ex. lampreys,
leeches, fleas,
ticks, tapeworm
Symbiotic Relationships
Mutualismboth species
benefit
Ex. cleaning birds
and rhino
Mutualism: cleaning birds eat
the bugs off the rhino and
the rhino is now free of bugs
Type of
Species
relationship
harmed
Commensalism
Parasitism
Mutualism
= 1 species
Species
benefits
Species
neutral
Trophic Levels
Food Chains & Food Webs
LEARNING TARGETS
At the end of this lesson you should be able
to say
1. I can describe the different trophic
levels.
2. I can explain the 10% rule.
3. I can construct a food chain to explain
how matter flows through living systems
and the physical environment.
Trophic Levels
• Trophic levels represent feeding
steps and the transfering of energy
and matter in an ecosystem.
E
N
E
R
G
Y
Trophic Levels
Tertiary
consumers- top
carnivores
Secondary consumerssmall carnivores
Primary consumers- Herbivores
Producers- Autotrophs
Trophic Levels
• As you move up both the amount of
energy and biomass decrease.
• Energy is transferred upwards but is
diminished with each transfer.
E
N
E
R
G
Y
Trophic Levels
Tertiary
consumers- top
carnivores
Secondary consumerssmall carnivores
Primary consumers- Herbivores
Producers- Autotrophs
Energy Pyramid
Energy pyramidgraphic
representation
of the relative
amounts of
energy or matter
at each trophic
level
Which level obtains the most
amount of energy from the sun?
• The
Whichproducer
or bottom
level obtains
the most
amount of
energy from
the sun.
10% Rule
10% Rule: As the energy moves up
the pyramid or food chain, only
10% of the energy from the
previous level will transfer to the
next.
Trophic Levels
Food chainsimple model
that shows
the flow of
matter and
energy
through an
ecosystem
What would be the effect on the
food chain if the cricket population
decreased in size?
The mouse,
snake and hawk
population would
decrease in size.
Trophic Levels
Food web-represents a network of
interconnected food chains
Food chain
(just 1 path of energy)
Food web
(all possible energy paths)
What is the producer in this
food web?
The grass on
the bottom.
Which organisms are the
herbivores?
The rabbit,
mouse
and
grasshopper.
What would happen to the
bird population if the hawk
population increased?
The bird
population would
increase since
the hawk preys
on snakes and
birds are eaten
by snakes.
Which carnivores would be most
affected if the rabbit population
suddenly decreased?
The Fox and
Hawk would be
most affected.