1. Ch. 21.1 Community Ecology pp.397-402
Symbiosis = interactions of species living together
Sym = together; bio = life
Score these as the “game of life”
+ if organism wins or gains
- if organism loses
0 or neutral if no effect
Score for individual organism
Community Ecology involves interactions between__________?

2. Ch. 21.1 Community Ecology pp.397-402
Symbiosis
Predation = one organism in a community catches, kills, and consumes another organism
Predator = consumer (+)
Prey = producer (they produced the food, themselves) (-)
Predator/prey: +/-
Community Ecology involves interactions between__________?
Different species

3. Ch. 21.1 Community Ecology pp.397-402
Predation is a very strong pressure of natural selection
Herbivory = an organism eating plants (herbs)
Considered a form of predation
Defense mechanisms include structures like thorns and chemicals like nicotine

4. Ch. 21.1 Community Ecology pp.397-402
Defenses:
Structures
Chemicals
Mimicry = to copy
Camouflage = copy to hide

5. Ch. 21.1 Community Ecology pp.397-402
15 top camo
Bozeman mimicry

6. Ch. 21.1 Community Ecology pp.397-402
Aposematic coloration = bright warning colors

7. Ch. 21.1 Community Ecology pp.397-402
Mimicry continued: Batesian Mimicry= a harmless species copies a harmful one

8. Ch. 21.1 Community Ecology pp.397-402
Mimicry continued: Müllerian mimicry = 2 harmful species evolve to look alike

9. Ch. 21.1 Community Ecology pp.397-402
Symbioses:
2. Parasitism = one organism feeds slowly on another organism
parasite = feeds
Host = is fed on
Parasite/host: +/-
Ecto = outside
Endo = inside

10. Ch. 21.1 Community Ecology pp.397-402
Ectoparasite: ticks

11. Ch. 21.1 Community Ecology pp.397-402
Endoparasite:
Roundworm in humans
Bacteria? Yes or no
Viruses? yes

12. Ch. 21.1 Community Ecology pp.397-402
Symbioses:
3. Mutualism = interaction in which both species benefit
+/+ win/win
Often evolved together
Good Bacteria and host
Honeybees and flowering plants
Alligator and Egyptian Plover

13. Ch. 21.1 Community Ecology pp.397-402
4. Commensalism = interaction in which one species benefits and the other is unaffected
+/0, win/neutral
Egrets and cattle
Crows and humans

14. Ch. 21.1 Community Ecology pp.397-402
5. Competition = when niches overlap, so 2 species try to use the same resource
What is the score?

15. Ch. 21.1 Community Ecology pp.397-402
5. Competition = when niches overlap, so 2 species try to use the same resource
What is the score?
-/- , lose/lose
There are costs for both

16. Ch. 21.1 Community Ecology pp.397-402
5. Competition = when niches overlap, so 2 species try to use the same resource The competition can be reduced by: Competitive exclusion = one species out competes another so it is removed Character displacement = evolution to change niche Resource partitioning = change which resources are used in the niche