1. The Marine Research Facility
Malibu High School
P r e s e n t s
c o l o g y
basics 5.

2. THE 10% RULE
and
ECOLOGICAL PYRAMIDS

3. The Laws of Thermodynamics and
FOOD CHAINS !

4. The
10 %
RULE !

5. trophic level is used to keep the
The maximum amount of ENERGY that passes from one trophic level to the next is 10%.
90% of the ENERGY at each
trophic level is used to keep the
organisms alive and is
converted to HEAT.

6. Always start
with the SUN.

7. HEAT 90% of the ENERGY captured by PRODUCERS is used to keep
The 10% RULE !
PHYTOPLANKTON
90% of the
ENERGY captured
by PRODUCERS
is used to keep
themselves
alive (converted
to heat).
HEAT
Max. 10 % to
HERBIVORES

8. of the pyramid of biomass because their ENERGY comes direct
PRODUCERS
HERBIVORES
1st Order
CARNIVORES
Producers are the BASE
of the pyramid of biomass because
their ENERGY comes direct
from the SUN.
2nd Order
CARNIVORES
3rd Order
CARNIVORES

9. HEAT Max. 10 % to CARNIVORES The 10% RULE ! 10% 90% 90% was used
PHYTOPLANKTON
10%
ZOOPLANKTON
90%
HEAT
90% was used
to keep the
HERBIVORES
alive.
Max. 10 % to
CARNIVORES

10. PRODUCERS HERBIVORES 1st Order CARNIVORES 2nd Order CARNIVORES
exist on only 10%
of the ENERGY
from PRODUCERS.
2nd Order
CARNIVORES
3rd Order
CARNIVORES

11. HEAT The 10% RULE ! 10% 10% 90% 10% PHYTOPLANKTON ZOOPLANKTON
1st Order CARNIVORES
90%
HEAT
10%
Max. 10 % to
2nd O. CARNIVORES

12. 1st O. Carnivores are max.10%
PRODUCERS
HERBIVORES
1st Order
CARNIVORES
2nd Order
CARNIVORES
3rd Order
CARNIVORES
1st O. Carnivores are max.10%
of HERBIVORES.

13. The 10% RULE ! 10% 10% 10% 2nd Order CARNIVORES PHYTOPLANKTON
ZOOPLANKTON
10%
1st Order CARNIVORES
10%
2nd Order CARNIVORES

14. ENERGY left near the top.
PRODUCERS
HERBIVORES
1st Order
CARNIVORES
2nd Order
CARNIVORES
3rd Order
CARNIVORES
There isn’t much
ENERGY left near the top.

15. PRODUCERS HERBIVORES 1st Order CARNIVORES 2nd Order CARNIVORES
The 10%
RULE . . .
2nd Order
CARNIVORES
3rd Order
CARNIVORES
...results
in this
ECOLOGICAL
PYRAMID

16. PRODUCERS - 1000 HERBIVORES - 100 1st Order CARNIVORES - 10 2nd Order
The 10%
RULE . . .
2nd Order
CARNIVORES - 1
3rd Order
CARNIVORES
0.1
...is used
to help
predict
NUMBERS.

17. 1000 100 10 1 0.1 The 10% RULE . . . ...is used to help predict
BIOMASS.
0.1

18. The ecological pyramid at ZUMA.
PHYTOPLANKTON
10%
ZOOPLANKTON
10%
1st Order CARNIVORES
10%
2nd Order CARNIVORES

19. 1,000 100 10 1 Population size ratios at ZUMA. 10% 10% 10% individuals

20. Biomass at
ZUMA.
pounds
1,000
pounds
10%
100
pounds
10% 10
10% 1
pound

21. ? 1 lb. For every 1 lb. of halibut, how many lbs. of Zalophus
can be supported ?
1 lb. ?

22. 1 lb. 0.1 lbs For every 1 lb. of halibut, 0.1 lbs. of Zalophus
can be supported !
1 lb.
0.1 lbs

23. 30,000 lbs. 3,000 lbs. For a 30 lb. halibut, 30,000 lbs.
of phytoplankton
are necessary !
PHYTOPLANKTON
30,000 lbs.
3,000 lbs.
ZOOPLANKTON
1st Order CARNIVORES
300 lbs.
30 lbs.
2nd Order CARNIVORES

24. REVIEW CHECKPOINT: 1. What is the 10% rule ?
2. Where does most of the ENERGY go
at each trophic level ?
3. What 2 things can the ecological
pyramid help predict?
4. If there are 14,963 kg of anchovies at
Zuma, tell how many kg are predicted:
a. Zooplankton c. Halibut
b. Phytoplankton d. Zalophus

25. Coming soon:
FOOD WEBS !