1 / 38

Ecology of Communities

Ecology of Communities. Types of Species Interactions. Tuesday 9/5/06 Pages 397-402 Section 21-1. Species Interactions. Close interaction between species. Predation Parasitism Competition Mutualism Commensalism. Which community is most diverse? Why?.

callie-adams
Download Presentation

Ecology of Communities

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ecology of Communities Types of Species Interactions

  2. Tuesday 9/5/06Pages 397-402Section 21-1 Species Interactions • Close interaction between species. • Predation • Parasitism • Competition • Mutualism • Commensalism Which community is most diverse? Why?

  3. Tuesday 9/05/06Pages 397-402Section 21-1 Predation • Predators capture, kill, and consume prey. • Predators are adapted to role. • Prey are adapted to survive predator Which species determines the number of the other?

  4. Tuesday 9/05/06Pages 397-402Section 21-1 Predation • Mimicry • Prey evolve defenses through natural selection. • Coloration mimics poisonous organism. • Warning coloration Why is the western King Snake not colored like the Arizona King Snake?

  5. Mimicry • Batesian mimicry • One poisonous, one not • Mullerian mimicry • Both poisonous

  6. Tuesday 9/05/06Pages 397-402Section 21-1 Predation • Plant - Herbivore • Plants are defending against herbivory. • Thorns, spines, sticky hairs. • Secondary chemicals • Nicotine • Strychnine • Digitalis • Poison oak What animal group is the plant trying to discourage?

  7. Tuesday 9/05/06Pages 397-402Section 21-1 Parasitism • Parasite is helped. • Host is harmed. • Ectoparsites • Endoparasites Why does a parasite usually not kill its host?

  8. Modern Biology Pages 397-402Section 21-1 Mutualism • Both species benefit. • Lichens • 2 layers of fungi • Algae cells inside. • Algae is kept moist • Fungi get food. Are mutualism relationships species specific?

  9. Modern Biology Pages 397-402Section 21-1 Commensalism • One species benefits. • One species is not effected. • Lichens growing on a tree limb. • Cattle egrets and live stock.

  10. Modern BiologyPages 397-402Section 21-1 Competition • Results from fundamental niche overlap. • Competitive exclusion. • When two species directly compete, one will go extinct. What, most likely, is being competed for in this study?

  11. Modern Biology Pages 397-402Section 21-1 Competition • Results from fundamental niche overlap. • Character displacement • Competitors evolve to different niches. How does the Barn Owl and Red Tail Hawk demonstrate character displacement?

  12. Modern Biology Pages 397-402Section 21-1 Competition • Results from fundamental niche overlap. • Resource partitioning. • Each competing species uses a portion of the resource. • Results in less competition between species. How does the Cape may Warbler differ from the rest of the warbler species?

  13. Review Pages 397-402Section 21-1

  14. Review Pages 397-402Section 21-1

  15. Modern Biology Pages 363-365 How is a fundamental niche different from a realized niche? • Fundamental niche • Full range of interactions in ecosystem. • All potential resources • Theoretical niche as if no other organisms present Why is the realized niche shown above smaller than the fundamental niche? Key Words: Fundamental niche Realized niche

  16. Modern Biology • Pages 371-372 Ecology of Organisms • Realized niche • All resources actually used. • Competition with other organisms limits fundamental niche. • Something less than the fundamental niche. Which species out competes the other species regarding niche?

  17. Modern BiologyPages 397-402Section 21-1 Properties of Communities • Species richness. • The total number of species in an ecosystem.

  18. Modern BiologyPages 397-402Section 21-1 Properties of Communities • Species diversity. • The total number of species in an ecosystem. • Also accounts for the number of each species.

  19. Modern BiologyPages 397-402Section 21-1 Patterns of Species Richness • Closer to the equator, the greater the richness. • Reasons why: • Older communities in tropics. • Stable climate • More available energy

  20. Modern BiologyPages 397-402Section 21-1 Succession • Gradual regrowth of species after a disruption. • Two types of succession: • Primary (starts with pioneer species) • Secondary (occurs after disruption) • Fire • Flood • Storm • Human activity • Farming

  21. Modern BiologyPages 397-402Section 21-1 Primary Succession • Starts slow due to lack of minerals. • Pioneer species first appear. • Eventually soil is produced. • Grasses appear. • Shrubs appear. • Finally trees appear.

  22. Modern BiologyPages 397-402Section 21-1 Secondary Succession • Disturbance leaves just soil intact. • Secondary succession starts with grasses. • A stable climax community results. • Some communities never reach stable climax community.

  23. Energy Transfers in Communities

  24. Monday 3/23/03Pages 415-419Section 22-1 Producers • Producers use energy to produce organic molecules. • Autotrophs • Use energy to produce carbohydrates. • Most are photosynthetic. • Few are chemosynthetic.

  25. Monday 3/23/03Pages 415-419Section 22-1 Measuring Productivity • Gross Primary productivity: • The rate at which producers capture energy. • Equal to all of the carbohydrates produced using photosynthesis.

  26. Monday 3/23/03Pages 415-419Section 22-1 Measuring Productivity • Net Primary Productivity. • All organic material in an ecosystem is referred to as biomass. • All stored energy in the ecosystem. • Rate at which biomass accumulates is NPP. • GPP - carbohydrates used for living.

  27. Monday 3/23/03Pages 415-419Section 22-1 Consumers • Consumers are heterotrophs. • Obtain energy by consuming organic molecules. • Herbivores • Carnivore • Omnivore • Detritivore • Decomposers

  28. Monday 3/23/03Pages 415-419Section 22-1 Energy Flow • Energy is transferred from organism to organism. • Trophic level refers to feeding position in community • Trophic levels: • 1st level = producers • 2nd level = herbivores • 3rd level = carnivore • 4th level = second carnivore

  29. Monday 3/23/03Pages 415-419Section 22-1 Food Chains • A single pathway of energy through the ecosystem. • Approximately 10% of energy is preserved in each transfer. • 5% of sun’s energy is preserved in the producers.

  30. Monday 3/23/03Pages 415-419Section 22-1 Food Webs • Several food chains interlinked. • Better shows energy flow in an ecosystem.

  31. Monday 3/23/03Pages 415-419Section 22-1 Food Webs • Several food chains interlinked. • Better shows energy flow in an ecosystem.

  32. Wednesday 3/25/03Pages 420-423Section 22-2 Biogeochemical Cycle • Energy flows through an ecosystem. • Water and minerals recycle in the ecosystem. • Water Nitrogen • Minerals Calcium • Carbon Phosphorus

  33. Wednesday 3/25/03Pages 420-423Section 22-2 Water Cycle • Availability of water determines productivity. • Evaporation • Transpiration • Precipitation • 90% of water that evaporates in ecosystem passes through plants.

  34. Wednesday 3/25/03Pages 420-423Section 22-2 Carbon Cycle • Carbon cycle is composed of two processes: • Photosynthesis • Respiration • Autotrophs do ____. • Heterotrophs do ____. • Detritivores do ____. • Decomposers do ____.

  35. Wednesday 3/25/03Pages 420-423Section 22-2 Nitrogen Cycle • All living organisms need nitrogen (N2) • 78% of the atmosphere is composed of N2. • Only usable to a few organisms. • Nitrogen fixation • Nitrogen fixation bacteria. • Breakdown of organic material results in ammonia. • Nitrogen is returned to the atmosphere.

  36. Modern BiologyPages 397-402Section 21-1 Species-Area effect • Larger areas support higher degree of richness. • Example: islands

  37. Modern BiologyPages 397-402Section 21-1 Community Stability • How well a community with stands change. • Species richness improves stability. • Experiment • Grass plots

More Related