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Mon. Tues. Wed. Thurs. Fri. Week of Oct. 27. Week of Nov. 3. Exam 2 no OH. no OH. Forest ecology lab – dress for weather . Week of Nov. 10. Independent project analysis . Week of Nov. 17. T lab switch?. Lab Exam . River ecology lab – dress for weather .
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Mon. Tues. Wed. Thurs. Fri. Week of Oct. 27 Week of Nov. 3 Exam 2 no OH no OH Forest ecology lab – dress for weather Week of Nov. 10 Independent project analysis Week of Nov. 17 T lab switch? Lab Exam River ecology lab – dress for weather
For exam: - Chaps. 6,7,8,13 - Chap. 14 – only equations and concepts we talked about in class - Chapter 15 – only through p. 302. Lab open for counting Lemna every day 10 - 4
Structure of course Environmental variability Organisms Ecosystems Populations Species interactions Communities Applied Ecological Issues
Species interactions Introduction Consumer/resources interactions (predation, herbivory, parasitism) Competition Mutualism
Change in pop. size of one species has an effect on growth rate of other species
Species interactions Introduction Consumer/resources interactions (predation, herbivory, parasitism) Competition Mutualism
Consumer/resource interactions - Consumer Resource + Arrows represent effect on growth rate
Consumer Resource Predator Prey Parasite Host Herbivore Plant/algae Detritivore Dead organic matter
Consumer/resource interactions • Predation • Herbivory • Parasitism • Dynamics of C/R interactions
Given that predators have adaptations that allow them to capture prey, why don’t predators drive their prey extinct?
Periodical cicadas 100% 6,000 Cicada mortality due to predation Live cicadas per 1,000 m2 3,000 0% 0 May 15 May 30 June 15 June 30 Decline due to thunderstorm
The predator’s predator - - Predator Prey +
Consumer/resource interactions • Predation • Herbivory • Parasitism • Dynamics of C/R interactions
Given that herbivores have adaptations that allow them to exploit resource, Why don’t herbivores drive plants extinct? Or Why is the world green?
Spatial refuge Figure 17.1
Production of population not individuals Cost Index of cone production
Consumer/resource interactions • Predation • Herbivory • Parasitism • Dynamics of C/R interactions
Parasites are incredibly diverse Examples?
Parasites on wood mice On skin – 1 sp. tick. On fur – 12 sp. of mites, 1 sp. tick, 11 sp. fleas, 1 sp. lice. In stomach – 1 sp. roundworm. In small intestine – 3 sp. roundworms, 3 sp. flatworms, 2 sp. flagellates, 1 sp. ciliate, 1 sp. amoeba. In liver – 1 sp. tapeworm. etc. 47 species not counting bacteria and viruses
pillbug = intermediate host tapeworm in a crow tapeworm changes pillbug behavior
Challenges for a parasite • 2. overcoming host defenses
Consumer/resource interactions • Predation • Herbivory • Parasitism • Dynamics of C/R interactions
Dynamics of consumer/resource interactions Consumers can reduce resource populations Examples of cycles Models of consumer/resource interactions
Figure 17.18 Effect on growth rate