HOW DO
POPULATIONS
INTERACT?
final chapter
Populations compete amongst themselves &
between other populations
…amongst themselves
Populations compete amongst themselves &
between other populations
…amongst themselves
…between populations
dayum!
Populations compete amongst themselves &
beteen other populations…
…amongst themselves
…between populations
Populations COMPETE amongst themselves & beteen
other populations & BETWEEN TROPHIC LEVELS!
ECOLOGY PYRAMIDS show the FEEDING
RELATIONSHIPS among a GROUP of ORGANISMS.
LET’S MAKE THREE!!!!
Kids get out their food webs,
paper template, scissors and cut
their pyramid sheet out. Gather
colored pencils.
ECOLOGY PYRAMIDS measure THREE THINGS!
1. NUMBERS
2. BIOMASS
3. ENERGY
3 ECOLOGY PYRAMIDS
1. NUMBERS of individuals
2. BIOMASS—amount of MASS they make up
3. ENERGY—the amount of energy (calories)
they ALL contain
LET’S START OFF
EASY…
ECOLOGY PYRAMIDS measure THREE THINGS!
1. NUMBERS of individuals
2. BIOMASS—amount of MASS they make up
3. ENERGY—the amount of energy (calories)
they ALL contain
Pick a critter off your food web that could be on
your FOURTH trophic level!
Pick a critter off your food web that could be on
your FOURTH trophic level!
Choose one of the pyramids as a NUMBERS
pyramid. DRAW or LABEL ONE of these
consumers here!
• He’s a TERTIARY
CONSUMER!
NUMBERS pyramid
Now check your food web to see what food this
consumer eats.
Draw &/or label 10x as many of these
secondary consumers here!
NUMBERS pyramid
• SO, IF YOU HAD 1
FOX AT THE TOP
OF YOUR
PYRAMID…HOW
MANY BIRDS
SHOULD YOU
HAVE AT THIS
TROPHIC LEVEL?
10
Now check your food web to find who your
PRIMARY CONSUMERS are
Draw &/or label 10x as many of these consumers
at your second trophic level here!
4th
3rd
2nd
1st trophic level
NUMBERS pyramid
• SO, IF YOU HAD
30 BIRDS, HOW
MANY BUNNIES,
GRASSHOPPERS
& MICE SHOULD
YOU HAVE AT
THIS LEVEL?
Draw &/or label 10x as many of these consumers
at your second trophic level here!
4th
3rd
2nd
1st trophic level
NUMBERS pyramid
• SO, IF YOU HAD
10 BIRDS, HOW
MANY BUNNIES,
GRASSHOPPERS
& MICE SHOULD
YOU HAVE AT
THIS 2ND LEVEL?
100!!!!!!
Check for your autotrophs…
Draw and/or label all your producer/autotroph
(plants & stuff) down here, MULTIPLIED by 10!!
4th
3rd
2nd
1st trophic level
NUMBERS pyramid
• So, how many
numbers of
producers
/autotrophs are
at the base of
this numbers
pyramid?
•1000
DON’T FORGET TO PUT
NUMBERS IN YOUR
NUMBERS PYRAMID!
As you move UP each trophic level, how many
organisms are available at next higher trophic
level?
4th
3rd
2nd
1st trophic level
NUMBERS pyramid
A.
B.
C.
D.
10%
50%
90%
100%
As you move up each trophic level, how many
organisms are available at next higher trophic
level?
4th
3rd
2nd
1st trophic level
NUMBERS pyramid
A.
B.
C.
D.
only 10%
50%
90%
100%
NUMBERS ECOLOGY PYRAMID:
LET’S DO ANOTHER..
http://www.brainpop.com/games/foodchaingame /#
http://www.akidsheart.com/animals/sea/foodchain/f
oodchain.html
LET’S DO ANOTHER…
PICK AN ADJOINING
EMPTY PYRAMID YOU
HAVEN’T FILLED IN
WE’LL CALL THIS A
BIOMASS PYRAMID
DO YOU REMEMBER
WHAT BIOMASS IS?
BIOMASS is the total amount of living or
recently living matter in our world.
Our BIOMASS PYRAMID measures the MASS of
BIOMASS in EACH TROPHIC LEVEL
NOTE HOW WE
MEASURE EACH
TROPHIC LEVEL
IN MASS (Kg)
RATHER THAN
IN NUMBERS.
we’ll call this a BIOMASS PYRAMID
BIOMASS pyramid
DOES
BIOMASS
INCREASE or
DECREASE as
you MOVE
DOWN to the
1ST TROPHIC
LEVEL?
we’ll call this a BIOMASS PYRAMID
BIOMASS pyramid
DOES
BIOMASS
INCREASES as
you MOVE
DOWN to the
1ST TROPHIC
LEVEL.
WHY?
Just look outside. Isn’t it OBVIOUS? Most life in
our world are producers.
HOW MUCH is BIOMASS REDUCED as
you go UP EACH TROPHIC LEVEL?
A.
B.
C.
D.
BIOMASS pyramid
10%
50%
90%
100%DO
ES
HOW MUCH is BIOMASS REDUCED as
you go UP EACH TROPHIC LEVEL?
A.
B.
C.
D.
BIOMASS pyramid
10%
50%
90%
100%DO
ES
So, if you are a WHALE & you
need to eat a LOT each day,
would you feed on higher or
lower trophic levels?
So, if you are a WHALE & you
need to eat a LOT each day,
would you feed on higher or
lower trophic levels?
LOWER…there’s more food
down here!
So, if we have to feed more people on Earth,
will we need to eat more meats or produce?
A.
B.
C.
D.
10%
50%
90%
100%DO
ES
BIOMASS pyramid
So, if we have to feed more people on Earth,
we need to eat more produce?
A.
B.
C.
D.
10%
50%
90%
100%DO
ES
BIOMASS pyramid
Make sure your BIOMASS pyramid has actual
MASS in KILOGRAMS on it!
A.
B.
C.
D.
10%
50%
90%
100%DO
ES
BIOMASS pyramid
LAST ONE!
HOW DOES ENERGY
FLOW WITHIN A FOOD
WEB?
Let’s do our last ecology
pyramid…pick the right side so
you can make a pyramid!
ENERGY PYRAMIDS measure the amount of energy
in KILOCALORIES available at each trophic level.
Like the
other
pyramids,
where is
most of the
energy
stored in
our world’s
food?
ENERGY pyramid
ENERGY PYRAMIDS measure the amount of energy
available at each trophic level.
Like the
other
pyramids,
where is
most of the
energy
stored in
our world’s
food?
ENERGY pyramid
MOST of our world’s food ENERGY is stored within
our AUTOTROPHS because they get their energy
FROM WHERE?
ENERGY pyramid
Like the
other
pyramids,
where is
most of the
energy
stored in
our world’s
food?
the
BOTTOM!
MOST of our world’s food ENERGY is stored within
our AUTOTROPHS because they get their energy
FROM THE SUN!!!
We measure
biomass in
kilograms
(Kg), what
do we
measure
ENERGY in?
ENERGY pyramid
We measure biomass in kilograms (Kg), what do
we measure ENERGY in? KILOCALORIES (kcal)!
Make sure your
ENERGY
pyramid is labels
with
KILOCALORIES
(kcal)!!!
ENERGY pyramid
What percent of ENERGY is LOST as you
GO UP each TROPHIC LEVEL?
A. 10%
B. 50%
C. 90%
D. 100%
ENERGY pyramid
What percent of ENERGY is LOST as you GO
UP each TROPHIC LEVEL?
A. 10%
B. 50%
C. 90%
D. 100%
ENERGY pyramid
Only 10% of chemical energy is available to
the next highest trophic level.
%Where
does 90%
of the
energy go?
ENERGY pyramid
As we EAT we lose body _ _ _ _!
• http://www.youtube.com/watch?v=thhsuwYt_hQ
As we EAT we LOSE body HEAT!
• http://www.youtube.com/watch?v=thhsuwYt_hQ
Only 10% of chemical energy is available to
the next highest trophic level.
Most energy
is lost by
higher level
consumers as
HEAT
ENERGY pyramid
Only 10% of chemical energy is available to the next
highest trophic level. MOST ENERGY IS LOST AS
HEAT!
Draw this
arrow &
note
what’s
written
inside!
ENERGY pyramid
REMEMBER THE RULE OF 10: As you go up a
trophic level, only 10% of the NUMBERS, MASS &
ENERGY is avaible for the next level.
• tiered discussion follows…
WHY IS THERE THE
MOST ENERGY WITH
PRODUCERS???
….that 1 st trophic level?
Decomposers
MOST
ENERGY
AVAILABLE
PRIMARY
SECONDARY
TERTIARY
TROPHIC LEVELS represent TRANSFERS OF ENERGY
from one organism to another.
Decomposers
MOST
ENERGY
AVAILABLE
PRIMARY
SECONDARY
LEAST
ENERGY
TERTIARY
AVAILABLE
TROPHIC LEVELS represent TRANSFERS OF ENERGY
from one organism to another.
WHICH NEEDS MORE ENERGY TO GET FOOD?
LOW LEVEL PRODUCERS?
UPPER LEVEL CONSUMERS?
MOST
ENERGY
AVAILABLE
Decomposers
PRIMARY
SECONDARY
LEAST
ENERGY
TERTIARY
AVAILABLE
Upper trophic levels have the least energy available &
they use the most energy to hunt, flee & reproduce.
Do we lose or gain energy as we go up trophic
levels?
We LOSE 90% of energy as we go up trophic levels!
When dinosaurs’ environment changed, there was
NOT enough food energy to meet their
GARGANTUAN energy needs at higher trophic
levels!
Decomposers
MOST
ENERGY
AVAILABLE
PRIMARY
SECONDARY
LEAST
ENERGY
TERTIARY
AVAILABLE
TROPHIC LEVELS represent TRANSFERS OF ENERGY
from one organism to another.
Your PYRAMID should have THREE (3) SIDES!
ENERGY
BIOMASS
NUMBERS
SOME FOLLOW-UP
QUESTIONS…
If the world becomes way too overpopulated,
why will we eat less meat?
What costs less:
• Pound of apples or pound of shrimp?
• Pound of bread or a pound of hamburger?
• Pound of sugar or pound of chicken?
What costs less: WHY?????
• Pound of apples or pound of shrimp?
• Pound of bread or a pound of hamburger?
• Pound of sugar or pound of chicken?
BIOMASS ecology PYRAMID:
Energy pyramid…
• http://www.youtube.com/watch?v=CReZd9OHEfs
ENERGY ecological PYRAMID:
ENERGY ecological PYRAMID:
ENERGY ecological PYRAMID:
ENERGY ecological PYRAMID: We lose more
energy the higher trophic levels we go!
As we EAT, we LOSE ENERGY as body HEAT!
http://www.youtube.com/watch?v=thhsuwYt_hQ
Your ecology pyramid should have three (3) sides:
ENERGY
BIOMASS
NUMBERS
DON’T FORGET TO SHOW THE FOLLOWING!
NUMBERS pyramid:
• show, label & draw numbers
of producers, consumers
(primary…etc.)
BIOMASS pyramid:
• show, label and draw
different organisms, show
masses with the RULE of 10
ENERGY pyramid:
• show, label and draw
different organisms, show
energies with the RULE of 10