Ch. 17 : Biological Communities

1. Ch. 17 : Biological Communities By: Brianna Shields March 24, 2006

2. Coevolution Predation Parasitism Secondary Compound Symbiosis Mutualism Commensalism Competition Niche Fundamental Niche Realized Niche Competitive Exclusion Biodiversity Climate Biome Littoral Zone Limnetic Zone Profundal Zone Plankton List the terms in your vocab notebook, leaving about 3-4 spaces between each term

3. DO NOW • Which cycle requires the nutrient to be released into the soil by dissolving rock? • Which food chain member possesses the greatest amount of available energy? • Which member of a food web is considered to be a primary consumer?

4. GOALS • Describe coevolution • Predict how coevolution can affect interactions between species • Identify the distinguishing features of symbiotic relationships • Describe the role of competition in shaping the nature of communities • Distinguish between fundamental and realized niches • Describe how competition affects an ecosystem • Summarize the importance of biodiversity • Recognize the role of climate in determining the nature of a biological community • Describe how elevation and latitude affect the distribution of the Earth’s major biomes • Compare features of plants and animals found in different biomes • Compare and contrast the major freshwater and marine habitats

5. Coevolution Back and forth evolutionary adjustments between interacting members of an ecosystem Biological Communities

6. Coevolution • Example: • flower adaptations appeared promoting the dispersal of their pollen • adaptations appeared in pollinators allowing them to obtain food from the flowers they’re pollinating

7. Predation Act of one organism killing another for food Biological Communities

8. Predation Example • Ex: snake eating a mouse • Ex: spider eating a an insect

9. Parasitism One organism lives in or on another One benefits, host is harmed Ex: lice, ticks, mosquitoes Biological Communities

10. Plant Defenses Difficult for plants to escape from, avoid or fight off predators Use thorns, spines, prickles Secondary Compounds- defense chemicals Distasteful to other species Advertise toxicity Ex: Mustard Oils Biological Communities

11. Plant Defenses Example • Although mustard oils secondary compounds are toxic to most insects, cabbage butterfly larvae can break the oils down & digest them

12. Symbiosis Close, long-term relationship between organisms Biological Communities

13. Mutualism Both species benefit Biological Communities

14. Mutualism Example • Ants & Aphids • Aphids suck sugar fluids from plants • Honey dew exiting their aphid anus is milked by ants • Ants “guard” the aphids from predators

15. Commensalism One species benefits, other is unharmed Biological Communities

16. Commensalism • Tropical fish and sea anemones • Fish hide in are protected by sea anemones (fish are immune to their stinging cells) • Sea anemones sting many other types of fish

17. Assessment • Explain why predator-prey coevolution can be described as an “arms race”. • Is the relationship between a plant and its pollinator mutualistic? Why or why not? • In a relationship that is an example of commensalism, would the species that is neither helped or harmed evolve in response to the other species? Defend your answer. • In Japan, native honeybees have an effective defense strategy against giant Japanese hornets. Imported European honeybees, however, are unable to defend themselves. Use this example to illustrate the results of natural selection in adaptation.

18. Competition Biological interaction that results when two species use the same resources Food Nesting Sites Living Space Light Nutrients Water How Competition Shapes Communities

19. Niche Function of a species in the ecosystem (job or pattern of living) How the species contributes to energy flow in the ecosystem Overlapping niches = competition Space utilization Food consumption Temperature range Mating factors How Competition Shapes Communities

20. Niche • Jaguar feeds on mammals, fish and turtles

21. Fundamental Niche Entire range of resource opportunities an organism can potentially occupy How Competition Shapes Communities

22. Fundamental Niche • Ex: Cape May Warbler • Summers in North Eastern U.S. and Canada • Nest in midsummer • Eats small insects • Searches for food high atop Spruce

23. Realized Niche Part of a fundamental niche that a species occupies May only occupy a part because it divides up resources with potential competitors Competition can limit how species use resources How Competition Shapes Communities

24. Realized Niche • Cape May Warblers can feed on insects all over a Spruce Tree, but they stay mainly at the top. • Remaining portions of the Spruce are divided among its potential competitors

25. Competitive Exclusion Elimination of a competing species Species using resources more efficiently will eliminate the other How Competition Shapes Communities

26. Competitive Exclusion • Small paramecium compete with larger paramecium because the have similar niches • Larger ones are driven to extinction, because smaller ones are resistant to bacterial waste products

29. Coexistence of Competitors If the niches of two potentially competitive species don’t overlap too much, coexistence can occur How Competition Shapes Communities

31. Coexistence of Competitors • 2 paramecium that potentially compete, have the same fundamental niche (living in a culture tube) • They have different realized niches • One better living at top due to high oxygen and bacteria to feed on • Other better living at bottom due to low oxygen and high concentration of yeast to feed on

32. Predation Predation reduces competition and increases biodiversity Biodiversity- variety of living organisms in a community How Competition Shapes Communities

33. Predation and Competition • Sea Stars are fierce predators • When removed from an intertidal community, the number of prey such as clams and mussels declined • Normally mussels easily outcompete all other types of prey species for space on rocks • Seas stars keep mussel populations low by prohibiting them from outcompeting similar species

34. Biodiversity Increased biodiversity leads to greater productivity and greater stability How Competition Shapes Communities

36. Biodiversity • Prairie plots with more plant species produced greater amounts of plant material and recovered from drought quicker than plots with fewer plant species

37. Assessment • Distinguish between niche and habitat • Describe the conclusions reached by Connell and Paine about how competition affects ecosystems • Describe how Tilman’s prairie- plot experiments demonstrate the effects of biodiversity on productivity and stability. • Can an organism’s realized niche be larger than its fundamental niche? Justify your answer. • A scientist finds no evidence that species in a community are competing and concludes that competition never played a role in the development of this community. Is this conclusion valid? Why? • When two species use the same resource, one species may drive the other to extinction. What is this phenomenon called?

38. Climate Prevailing weather conditions in any given area 1. Temperature Optimal ranges for certain species Influences growing season 2. Moisture Rainfall patterns determines area’s lifeforms Moisture holding ability of air increases with temperature Major Biological Communities

39. Biome Major biological community occurring over a large area of land Soil Type Wind Temperature Precipitation Major Biological Communities

41. Biome As latitude and elevation increase Temperature decreases Moisture holding ability of air decreases Major Biological Communities

42. Tropical Rainforest Great amount of rainfall High biodiversity High primary productivity Poor soil Major Biological Communities

43. Savannas Dry grasslands Low precipitation Seasonal drought Open landscape, few trees Major Biological Communities

44. Taiga Long, cold winters Coniferous trees Large mammals Covers vast areas Major Biological Communities

45. Tundra Covers 1/5 of Earth’s land Low precipitation Frozen water Permafrost ground Major Biological Communities

46. Desert Low precipitation Sparse vegetation Interiors of continents Major Biological Communities

47. Temperate Grasslands Rich, prairie grass Interior of North America Highly productive agriculture Deep, fertile soil Major Biological Communities

48. Temperate Deciduous Forest Mild climate (warm summers, cold winters) Plentiful rain Leaf-shedding trees Eastern U.S. Major Biological Communities

49. Temperate Evergreen Forest Quite dry Evergreen growth (pines) Major Biological Communities

50. Freshwater Lakes, ponds, rivers, streams 2% of Earth’s surface Zones Littoral- shallow, shore water Limnetic- farther from shore, near surface Profundal- deep water, low light Major Biological Communities