120 likes | 397 Views
A. Niche. 1. How organisms utilize their environment2. Niche is a pattern of living, while habitat is a place3. Fundamental niche- niche a species is capable of occupying
E N D
1. XVI. Community Ecology A. Niche
B. Competitive Exclusion
C. Predator-Prey Relationships
D. Mimicry
E. Symbiotic Relationships
2. A. Niche 1. How organisms utilize their environment
2. Niche is a pattern of living, while habitat is a place
3. Fundamental niche- niche a species is capable of occupying & utilizing
4. Realized niche- niche the species actually occupies & uses
3. B. Competitive Exclusion 1. If resources are limited, no two species can occupy & use the same niche indefinitely
2. Competition drives one species to extinction
3. Partitioning the niche avoids competition
4. Partitioned by different areas of habitat, different food sources, &/or different times
4. C. Predator-Prey Relationships 1. Predators control prey populations & prey control predator populations
2. Predator-prey interaction provides strong selective pressure on both populations
3. Predators & prey coevolve
4. Mesozoic fish could crush & eat molluscs, molluscs evolved thicker shells with defensive spines
5. D. Mimicry 1. Batesian
2. Mullerian
6. 1. Batesian Mimicry a. Harmless species resembles dangerous or unpleasant species
b. Monarch & viceroy butterflies
c. Coral snake & Scarlet Kingsnake; if nose is black, jump back Jack; if nose is red, nothing to dread
7. 2. Mullerian Mimicry Two or more unrelated but protected species resemble one another
b. Bees & wasps
8. E. Symbiotic Relationships 1. Two or more species living together in specific relationships
2. At least one benefits
3. Tend to coevolve
4. Commensalism
5. Mutualism
6. Parasitism
9. 4. Commensalism a. One species benefits, the other neither benefits nor is harmed
b. Barnacles & whales; humans & intestinal bacteria
c. Often hard to rule out if host is helped or harmed
10. 5. Mutualism a. Cooperation between species mutually benefits both
b. Coevolution of angiosperms & insects; some plants have one specific pollinator
c. Ants & acacia
11. 6. Parasitism a. One organism serves as a host to another organism
b. Host is harmed, but not killed
c. Parasite is much smaller than host
d. External- lice, fleas
e. Internal- tapeworms, flukes
12. Return to Lectures Menu