Levels of Organization in Ecosystems: Species, Populations, Communities, Ecosystems, and Biomes

1. Unit 7: Ecology Week 4: Species and Relationships

2. Bell Work • What are soils and how are they formed? • What are the different layers of soils?

3. SC Standards • Standard 7.EC.5: The student will demonstrate an understanding of how organisms interact with and respond to the biotic and abiotic components of their environments. • 7.EC.5A Conceptual Understanding: In all ecosystems, organisms and populations of organisms depend on their environmental interactions with other living things (biotic factors) and with physical (abiotic) factors (such as light, temperature, water, or soil quality). Disruptions to any component of an ecosystem can lead to shifts in its diversity and abundance of populations. • 7.EC.5A.1: Develop and use models to describe the characteristics of the levels of organization within ecosystems (including species, populations, communities, ecosystems, and biomes). • S.1A.2: Develop and use models to (1) understand or represent phenomena, processes, and relationships, (2) test devices or solutions, or (3) communicate ideas to others.

4. Monday’s Objectives • Essential Learning Experiences: It is essential that students develop and use models to describe the characteristics of the levels of organization within ecosystems

5. What we will Learn • The organization in the natural environment from most simple to most complex • species (individual organisms), populations, communities, ecosystems, and biomes. • Each level is defined by the type and number of biotic (organisms) and/or the abiotic (nonliving) factors present.

6. Species • The individual living organism • Organisms of the same species can reproduce to make more of that species • Example – whitetail deer This Photo by Unknown Author is licensed under CC BY-NC

7. Populations • All of the individuals of a given species in a specific area or region at a certain time. • Members of a population compete for food, water, space, and mates. • Example – all of the white tail deer in South Carolina This Photo by Unknown Author is licensed under CC BY-NC-ND

8. Communities • All the different populations in a specific area or region at a certain time. • Communities involve many types of interactions among the populations. • Some of these interactions involve the obtaining and use of food, space, or other environmental resources. • Example – all of the living organisms (biotic factors) in the environment with the white tail deer, including pine trees, grass, squirrels, moss, mushrooms, and Carolina wrens.

9. Ecosystems • One or more communities in an area and the abiotic factors, including water, sunlight, oxygen, temperature, and soil is an ecosystem. • Example – all of the living organisms (biotic factors) in the environment with the white tail deer, including pine trees, grass, squirrels, moss, mushrooms, and Carolina wrens as well as all of the abiotic (nonliving) factors such as rivers, soil, air, and rocks This Photo by Unknown Author is licensed under CC BY-SA

10. Biomes • Individual ecosystems grouped together according to the climate, the predominant vegetation, and characterized by adaptations of organisms to that particular environment. • Example – the temperate deciduous forest that the white tail deer lives in. This Photo by Unknown Author is licensed under CC BY-SA

11. Vocabulary • Species: • Community: • Biome • Population: • Ecosystem:

12. Review Questions • What is the level of organizations starting at the cellular level and going to biomes? • Explain the difference between a community and an ecosystem.

13. Unit 7: Ecology Lesson 3 Continued

14. Bell Work • List the abiotic and biotic factors in the classroom. • What is abiotic and biotic? •  What is the difference between a biome and an ecosystem?

15. Earth’s Biomes

16. Tropical Rain Forest Abiotic: warm and wet year-round; soils are thin and nutrient-poor • tropical rain forests are home to more species than all other biomes combined. • As the name suggests, rain forests get a lot of rain—at least 2 meters of it a year. • Tall trees form a dense, leafy covering called a canopy from 50 to 80 meters above the forest floor. • In the shade below the canopy, shorter trees and vines form a layer called the understory. • Organic matter on the forest floor is recycled and reused so quickly that the soil in most tropical rain forests is not very rich in nutrients. • Animals are active all year. • Many animals use camouflage to hide from predators; some can change color to match their surroundings. • Animals that live in the canopy have adaptations for climbing, jumping, and/or flight. Biotic: plants with large leaves and buttress tree roots; animals active year-round

17. Tropical Dry Forest Abiotic: warm year-round; alternating wet-dry seasons; rich soils • Tropical dry forests grow in areas where rainy seasons alternate with dry seasons. • In most places, a period of rain is followed by a prolonged period of drought. Biotic: deciduous plants, waxy plant leaves; many animals estivate or migrate

18. Tropical Grassland/Savanna/Scrubland Abiotic: warm; seasonal rainfall; compact soils; frequent fires set by lightning • Savanna receives more seasonal rainfall than deserts but less than tropical dry forests. • Grassy areas are spotted with isolated trees and small groves of trees and shrubs. • Compacted soils, fairly frequent fires, and the action of large animals—for example, rhinoceroses and elephants—prevent some areas from turning into dry forest. Biotic: plants with waxy leaves, seasonal leaf loss; many animals migrate or are dormant during dry season

19. Desert • Deserts have less than 25 centimeters of precipitation annually, but otherwise vary greatly, depending on elevation and latitude. • Many deserts undergo extreme daily temperature changes, alternating between hot and cold. Abiotic: low precipitation; variable temperatures; soils poor in organic material Biotic: small plant leaves; many animals nocturnal, many get water from their food

20. Temperate Grassland • Plains and prairies, underlain by fertile soils, once covered vast areas of the Midwestern and Central United States. • Periodic fires and heavy grazing by herbivores-maintained plant communities dominated by grasses. • Today, most have been converted for agriculture because their soil is so rich in nutrients and is ideal for growing crops. Abiotic: warm summers, cold winters; moderate precipitation; fertile soils; occasional fires Biotic: plants resistant to grazing and fire; small animals use camouflage and burrowing as protection

21. Temperate Woodland and Shrubland • open woodlands, large areas of grasses and wildflowers such as poppies are interspersed with oak and other trees. • Communities that are more shrubland than forest are known as chaparral. • Dense low plants that contain flammable oils make fire a constant threat. Abiotic: warm, dry summers; cool, moist winters; nutrient-poor soils; periodic fires Biotic: plants adapted to drought and fire; animals commonly browsers

22. Temperate Forest • Temperate forests are mostly made up of deciduous and evergreen coniferous trees. Coniferous trees, or conifers, produce seed-bearing cones, and most have leaves shaped like needles, which are coated in a waxy substance that helps reduce water loss. • These forests have cold winters. • In autumn, deciduous trees shed their leaves. • In spring, small plants burst from the ground and flower. • Fertile soils are often rich in humus, a material formed from decaying leaves and other organic matter. Abiotic: cold winters, warm summers; year-round precipitation; fertile soils Biotic: deciduous trees; some animals hibernate, some migrate in winter

23. Northwestern Coniferous Forest • Mild, moist air from the Pacific Ocean influenced by the Rocky Mountains provides abundant rainfall to this biome. • The forest includes a variety of conifers, from giant redwoods to spruce, fir, and hemlock, along with flowering trees and shrubs such as dogwood and rhododendron. • Moss often covers tree trunks and the forest floor. • Because of its lush vegetation, the northwestern coniferous forest is sometimes called a “temperate rain forest.” Abiotic: mild temperatures; abundant precipitation in fall, winter, and spring; cool, dry summers; rocky, acidic soils Biotic: dense plant growth, tall trees; many animals have varied diets

24. Boreal Forest • Forests of coniferous evergreens along the northern edge of the temperate zone are called boreal forests, or taiga. • Winters are bitterly cold • Summers are mild and long enough to allow the ground to thaw. • The word boreal comes from the Greek word for “north,” reflecting the fact that boreal forests occur mostly in the northern part of the Northern Hemisphere. Abiotic: long, cold winters; mild summers; moderate precipitation; acidic, nutrient-poor soils Biotic: dark-green conifers; many animals have extra insulation, some migrate in winter

25. Tundra Abiotic: strong winds; low precipitation; short, soggy summers; long, cold, dark winters; permafrost • tundra is characterized by permafrost, • Permafrost is a layer of permanently frozen subsoil. • During the short, cool summer, the ground thaws to a depth of a few centimeters and becomes soggy. • In winter, the top layer of soil freezes again. • This cycle of thawing and freezing, which rips and crushes plant roots • Tundra plants are small and stunted. • Cold temperatures, high winds, a short growing season, and humus-poor soils also limit plant height. Biotic: small plants growing low to the ground; many animals migrate in winter or have heat-saving adaptations

26. Vocabulary • Tundra: • Tropical Rain Forest: • Savanna • Desert: • Tropical dry forest:

27. Review Questions/Homework • When is the rainy season in this biome? • Why would wildfires be an even greater threat during this portion of the year? • Is this biome defined more by changes in average temperatures throughout the year or by changes in average precipitation throughout the year? • During what season does the biome get the least amount of rain? The greatest amount of rain? • What main factor distinguishes tropical rain forest from northwestern coniferous forest? • What is the lowest average temperature in Fairbanks? The highest average temperature? • Do you think heavy snowstorms and deep snowdrifts are a common winter feature in the tundra? Why or why not?   • Which other biome does this diagram remind you of in terms of precipitation?

28. Unit 7: Ecology Relationships

29. SC Standards • Standard 7.EC.5: The student will demonstrate an understanding of how organisms interact with and respond to the biotic and abiotic components of their environments. • 7.EC.5B Conceptual Understanding: Organisms in all ecosystems interact with and depend upon each other. Organisms with similar needs compete for limited resources. Food webs and energy pyramids are models that demonstrate how energy is transferred within an ecosystem. • 7.EC.5B.1: Develop and use models to explain how organisms interact in a competitive or mutually beneficial relationship for food, shelter, or space (including competition, mutualism, commensalism, parasitism, and predator-prey relationships). • S.1A.2: Develop and use models to (1) understand or represent phenomena, processes, and relationships, (2) test devices or solutions, or (3) communicate ideas to others.

30. SC Objectives • Essential Learning Experiences: It is essential that students develop and use models to explain how organisms interact in a competitive or mutually beneficial relationship for food, shelter, or space.

31. What we will be Covering • It is essential for students to understand the complex interactions between organisms in the environment. • In any given ecosystem, organisms have interactions that allow them greater access to resources. • These interactions can lead to competition for resources. • Consequently, relationships form that allow a greater number of species access to those resources. • We call these relationships symbiotic relationships. • Examples include competition, mutualism, commensalism, and parasitism.

32. Competition • Competition is a relationship that occurs when two or more organisms need the same resource at the same time. • Can be among the members of the same or different species • occurs with organisms that share the same niche. • Ecological niche refers to the role of an organism in its environment including type of food it eats, how it obtains its food and how it interacts with other organisms. • Two species with identical ecological nichescannot coexist in the same habitat. • Competition usually results in a decrease in the population of a species less adapted to compete for a particular resource.

33. Predator-Prey Relationship • Predation is an interaction between species in which one species (the predator) hunts, kills, and eats the other (prey). • This interaction helps regulate the population within an ecosystem thereby causing it to become stable. • Fluctuations in predator–prey populations are predictable. At some point the prey population grows so numerous that they are easy to find. • A graph of predator–prey density over time shows how the cycle of fluctuations results in a stable ecosystem. • As the prey population increases, the predator population increases. • As the predator population increases, the prey population decreases.

34. Predator-Pray Graph

35. Symbiosis • A symbiotic relationship exists between organisms of two different species that live together in direct contact. • The balance of the ecosystem is adapted to the symbiotic relationship. • If the population of one or other of the symbiotic organisms becomes unbalanced, the populations of both organisms will fluctuate in an uncharacteristic manner. • Symbiotic relationships include parasitism, mutualism, and commensalism.

36. Parasitism • Parasitism is a symbiotic relationship in which one organism (the parasite) benefits at the expense of the other organism (the host). • In general, the parasite does not kill the host. • Some parasites live within the host, such as tapeworms, heartworms, or bacteria. • Some parasites feed on the external surface of a host, such as aphids, fleas, or mistletoe. • The parasite-host populations that have survived have been those where neither has a devastating effect on the other. • Parasitism that results in the rapid death of the host is devastating to both the parasite and the host populations. • It is important that the host survive and thrive long enough for the parasite to reproduce and spread.

37. Mutualism • Mutualism is a symbiotic relationship in which both organisms benefit. • Because the two organisms work closely together, they help each other survive. • For example, bacteria, which have the ability to digest wood, live within the digestive tracts of termites; plant roots provide food for fungi that break down nutrients the plant needs.

38. Commensalism • Commensalism is a symbiotic relationship in which one organism benefits and the organism is not affected. • For example, barnacles that attach to whales are dispersed to different environments where they can obtain food and reproduce; burdock seeds that attach to organisms and are carried to locations where they can germinate.

39. Vocabulary • Competition: • Mutualism: • Parasitism: • Commensalism: • Symbiosis:

40. Review Questions • Name and describe a symbiotic relationship. • What is the difference between predation and parasitism? • What is the difference between mutualism and commensalism?