Chapter 5: Evolution and Community Ecology

1. Chapter 5: Evolution and Community Ecology Mr. Manskopf Notes Can Also Be Found at http://www.manskopf.com

2. Section 3: Ecological Communities • Explain the difference between producer and consumer. • Explain the effect of inefficient energy transfer on community structure. • TERMS: primary producer, photosynthesis, consumer, cellular respiration, herbivore, carnivore, omnivore, detritivore, decomposer, trophic level, food chain, biomass, food web, keystone species.

3. What makes an ecosystem like this “work?”

4. Life Depends ENERGY, LOTS OF ENERGY…from the Sun • Average Star • 93 million miles away • Nuclear Fusion • No Sun, No Life

5. Life Depends on the Sun ALL organisms need a constant supply of energy or they die Why do plants grow upwards?

6. Life Depends on the Sun • The ultimate source of almost all energy for organisms is the SUN. • What did you eat? (Nuclear Powered?) • Only some deep sea creatures do not get energy from sun Mmmm, solar energy tastes good!

7. Life Depends on the Sun • Photosynthesis: plants use the suns energy, water and CO2, to make energy. • Base of ALL food chains

8. Almost all organisms depend either directly or indirectly on photosynthesis

9. From Producer to Consumer • Producer: an organism that makes it own food • Plants • Autotrophs, self-feeders • Use sunlight • Base of all food chains

10. From Producer to Consumer • Consumer: gets it energy by eating producers or other consumers • Heterotrophs • Indirectly solar powered

11. Types of Consumers • Herbivore: eats only producers (vegetarian) • Cows, sheep, deer, grasshopper, mice, rabbits

12. Types of Consumers • Carnivore: eats other consumers • Lion, hawks, snakes, alligator, whales

13. Types of Consumers • Omnivore: eats both producers and consumers • Bears, pigs, raccoons and most humans

14. Types of Consumers • Decomposer: breaks down dead decaying organisms • Critical to ecosystem health • Returns nutrients • Fungus, bacteria

15. Detritivores and decomposers: recycle nutrients within the ecosystem by breaking down nonliving organic matter

16. How do Organisms Use Energy Most organisms spend large amounts of time/energy in search of food and a mate.

17. How do Organisms Use Energy • Cellular Respiration: processes of breaking down food to yield energy • Gives energy to walk, read, grow, think, run, fight diseases • Excess stored as fat

18. Glucose (sugar) + Oxygen yields carbon dioxide, water and energy REACTANTS PRODUCTS

20. Energy Transfer Each time one organism eats another, energy is transferred Ecosystems are all about energy flowing from one organism to another

21. Energy Transfer • Who are the producers? • Consumers? • Herbivores? • Carnivores? • Omnivores? • Decomposers? • Where does the energy start?

22. Energy Transfer • Food Chain: sequence in which energy is transferred from one organism to another • Starts with producers

23. Energy Flow • Food Web: shows many feeding relationships that are possible in a ecosystem • More complex and realistic

26. Energy Flow • Trophic Level: each step which energy is transferred

27. Energy Pyramid

28. Energy Flow • Why are there fewer organisms at the top? (Why fewer bears than the fruit they feed on) • Why aren’t there more than 4-5 trophic levels in a energy pyramid?

29. Energy Flow • At each trophic level about 90% of energy is lost • Cellular respiration • Lost to heat body and carry out living

31. Energy Flow • Why are there fewer organisms at the top? (Why fewer bears than the fruit they feed on) • Why aren’t there more than 4-5 trophic levels in a energy pyramid?

32. What does this diagram show?

34. Keystone Species • Species that have strong and/or wide-reaching effects on a community • Removal of a keystone species can significantly alter the structure of a community.

35. Keystone Species http://www.youtube.com/watch?v=Xg62WKwA470 (Otter Keystone Species) Prairie Dogs: Keystone species http://www.youtube.com/watch?v=kEh4r4iQiBU NATURE's "Silence of the Bees“ http://www.youtube.com/watch?v=dIUo3STj6tw

36. Section 3 Review • Explain the difference between producer and consumer. • Explain the effect of inefficient energy transfer on community structure. • TERMS: primary producer, photosynthesis, consumer, cellular respiration, herbivore, carnivore, omnivore, detritivore, decomposer, trophic level, food chain, biomass, food web, keystone species.

37. Section 3 Quiz B. The SUN 1) The ultimate source of energy in an ecosystem in which deer eat grass and coyotes eat deer is A. the grass. B. the sun. C. the deer. D. chemosynthesis.

38. 2) When energy is transferred between trophic levels, the amount of available energy lost is aboutA. 90 percent.B. 50 percent.C. 25 percent.D. 10 percent. A. 90%

39. 3) Humans are generallyA. carnivores.B. herbivores.C. omnivores.D.detrivores. C. Omnivores

40. 4) Any being that uses the sun’s energy to create sugars is aA. primary producer.B. secondary producer.C. primary consumer.D. secondary consumer. A. primary producer.

41. 5) In a food web that consists of grass, mice, deer, coyotes, and hawks, which species is likely to have the greatest biomass?A. grassB. miceC. coyotesD. hawks A. grass

42. 6) The first level of all food pyramidsA. consists of primary producers.B. consist of primary consumers.C. is chemosynthesis.D. is photosynthesis. A. consists of primary producers.

43. 7) Short Answer: In a meadow community, you observe a high biomass of plants, a fairly high number of rodents, but only a single fox. Explain. This is due to inefficient energy transfer through the food web. Only about 10 percent of energy is available from one level to the next, so a high biomass of plants will support only a few predators.

44. 8) Short Answer: Grasslands are generally considered highly productive ecosystems, and we see some of the largest and most diverse assemblages of mammal species on grasslands such as the Serengeti. Why do you think this is, as opposed to an ecosystem like a northern pine forest, for example? Grasslands produce a huge amount of available plant energy, which in turn supports a large number of herbivores, and a higher concentration of carnivores. A forest contains a lot of biomass as unavailable woody material that animals cannot easily consume, so energy remains locked at the producer level.

45. 9) Short Answer: Explain why a food web is a better representation of energy flow in a community than a food chain. A chain represents a single avenue of energy transfer. In reality, there are numerous relationships between a single species and the other species in its community, so energy might travel along any of several paths.

46. 10) Identify a producer, a primary consumer, and a secondary consumer from the illustration. Plants are producers. Deer, crayfish, moorhens, raccoons, shrimp, and flagfish are primary consumers. Pin frogs, bobcats, alligators, crayfish, killfish, largemouth bass, anhingas, and alligators are secondary consumers.

47. 11) If an anhinga consumes a crayfish, what percentage of the energy of the crayfish’s original plant-based meal will reach the anhinga? One percent of the original energy of the plants will be available to the anhinga.

48. 12) Which populations in this ecosystem would you expect to have the fewest members, and why? The anhingas, bobcats, and alligators would probably be fewer in number than other species, since they are secondary or tertiary consumers and much of the ecosystem’s energy has been lost by the time it reaches them.

49. 13) What would happen if alligators were removed from the ecosystem? Explain the effects on each level of the food web. The alligator’s prey species might increase, which might put pressure on plant resources and on other species that the alligator’s prey species eat. On the other hand, competitors of the alligator would most likely flourish, so anhingas might also experience an increase in population.

50. 14) Identify two species in this web that might compete with each other, and explain which resources they compete for. Alligators and bobcats are competing for food in the form of moorhens. Raccoons, moorhens, white-tailed deer, crayfish, glass shrimp, and flagfish compete for plant foods. Anhingas and alligators compete for pin frogs. Pin frogs and anhingas compete for crayfish. Bass and anhingas compete for killfish. Bass and killfish compete for grass shrimp and worms.