1. Ecology
Communities

2. Community Vocab. Community = all organisms in area
Species richness = # different species
determined by - abiotic factors
- food supply
- evolutionary history
- species interactions
- physical disturbances (frequency)
Highest in Tropics – high primary productivity
- old stable ecosystem

4. Niche =
role in ecosystem - all activites & interactions
Fundamental niche =
niche it would fill if not limited by competition
Realized niche =
actual role played,
area covered,
food used etc.

5. INTERACTIONS Can be…. A) Interspecific – between species
B) Intraspecific – within species
- competition, mates, social
C) Obligatory – needed for survival
D) Facultative – helpful but not necessary

6. Competition Intraspecific & Interspecific 2 types:
Interference Competition =
one species blocks access of
another species to some resource
Exploitative Competition =
one species is better at using the resource
so gets more

7. Competitive Exclusion Theory
2 species that use identical resources (identical niche)…
can not coexist indefinitely
One species will go extinct in that area
Gause - studied Paramecium sp.
- showed competitive exclusion

9. Resource Partitioning = subdividing resources to allow species to coexist

10. More types of interactions
1) Predation =
(+,-) One predator kills and eats
more than one prey organism

11. 2) Parasitoid =
(+,-) One parasitoid kills and eats
one host organism.

12. 3) Herbivory :
(+,-)herbivore eats plant

13. Symbiotic Relationships
Organisms live closley together
Names end in –ism
Parasitism
Mutualism
Commensalism

14. 4) Parasitism = (+,-) Many parasites feed on
one host organism….try not to kill host

15. 5) Mutualism =
(+,+) symbiotic relationship where
both benefit

16. 6) Commensalism = (+,0) one organism benefits
the other is not affected

17. More on Predator-Prey Interactions
Co-evolution: joint evolution of 2 species that exert selective pressure on each other
Lynx & Snowshoe hare
also common w/ mutualisms
Adaptations:
inherited genetic traits that improve an organism’s fitness

18. Adaptations Can Help plants avoid being eaten
Help predators capture prey
Help prey avoid predators
Match organisms to their habitat

19. 1.Cryptic Coloration Camouflage color Camouflage shape
Camouflage behavior

26. 2.Chemical Defense
Smell
Taste
Poison
venom

33. 3.Aposematic Coloration
Warning color
Red/orange
Black & some bright color

36. Arizona Coral Snake

38. Organism looks/behaves like a different organism
4. Mimicry
Organism looks/behaves like a different organism

39. 3 Types of Mimicry
1) A harmless/defenseless mimic
looks like a dangerous model
Batesian
Mimicry

40. Red next to black venom lack.

42. 2) Two dangerous/bad-tasting organisms mimic each-other
Mullerian
Mimicry

43. Monarch Viceroy

44. 3) Harmful predator/parasite mimics harmless model

45. Cleaner Wrasse Mimic
Saber-toothed Blenny * Cleaner Wrasse

47. 5. Physical Defense
Armor/Shell/Spines
Teeth/Claws
Speed/Size