1. Ecosystems
Interactions among living things

2. Natural Selection:
A process by which characteristics that make an individual better suited to it's environment become more common in the species.
Sometimes referred to as “survival of the fittest”

3. Long shallow roots, needles to protect from animals
Adaptations
Behaviors or physical characteristics that allow organisms to live successfully in their environment
Shell for protection
Long neck to reach leaves
Long shallow roots, needles to protect from animals

4. How Does Natural Selection work?
Those with the unique characteristics best suited for their environment will survive and produce offspring.
End result = ADAPTATIONS

5. English Peppered Moth –Natural selection in action
dark moth - random mutation
not as common
Soot covered tree
England 1800’s
camouflaged moth

6. Niche An organisms’ role in an ecosystem = niche.
Niche and Habitat are different
Address of an organism = Habitat
“Job” or “Profession” = Niche
Organism = tree
Habitat = Forest
Niche = produce oxygen
provide home for birds

7. Competition:
The struggle between organisms to survive as they attempt to use the same limited resources.

8. Three major types of interactions among organisms:
Competition
Predation
Symbiosis

9. Explain why two organisms cannot occupy the same niche:
If two species occupy the exact same niche in nature, one will die off due to competition for limited resources.

10. Predation:
An interaction in which one organism kills another for food.

11. Predator or Prey: Predator - organism that does the killing
Prey – organism that is killed.

12. Effect of predation on population size:
What variable is plotted on the x-axis? ______
What two variables are plotted on the y-axis? ________ and __________
years
# of moose
# of wolves

13. Effect of predation on population size:
How did the moose population change between 1965 and ___________
How did the wolf population change between 1973 and 1976? __________
It increased
It increased

14. Effect of predation on population size:
How might the change in moose population have lead to the change in wolf population?
The wolf preys on the moose so more moose meant more food for the wolf.

15. Effect of predation on population size:
How might disease in the wolf population one year affect the moose population the next year?
Disease in the wolf population might cause some to die. With less predators, the moose population would most likely increase.

16. Cheetah speed Owl eyes Jelly fish venom
Examples of Predator Adaptations
Cheetah speed
Owl eyes
Jelly fish venom

17. Defense strategies Mimicry Protective Covering False Coloring
Warning color
Camouflage

18. Symbiosis – a close relationship in nature that benefits at least one species
Bacteria from gut of termite
Termites

19. Symbiosis

20. Symbiotic Relationships
Types of Symbiotic relationships
Type of Relationship
How Species Are Affected
Mutualism
One species benefits, while the other is unharmed
Parasitism
Both species benefit
Commensalism
One species benefits while the other is harmed

21. Mutualism
Both species benefit

22. Commensalism
One species benefits, but the other isn’t harmed or helped.

23. Parasitism One species benefits and the other is harmed.
The one benefiting is the parasite
The one being harmed is a host