Chapter 2: Principles of Ecology

1. Chapter 2: Principles of Ecology Biology I

2. Section 1: Organisms and Their Relationships • Ecology – the scientific study of interactions between living organisms and their environment • Environment includes: • Physical surroundings, climate, interactions with other living organisms • Ecology also includes the study of the biosphere • Biosphere – the portions of the planet in which life exists • For example: Land, water, air, or space

3. Biotic and Abiotic Factors • Organisms living within ecosystems are influenced by a wide range of environmental factors. • There are two types of factors: • Biotic • Abiotic • Together, these factors determine: • The survival and growth of an organism/species. • The success of an ecosystem

4. What are They? • Biotic factors • Factors that are LIVING! (Bio = life!) • For example: plants, animals, bacteria, fungi • Abiotic factors • Those factors that are NONLIVING! (A = not!) • Often related to climate and weather • For example: temperature, sunlight, wind, soil, precipitation, humidity, pressure

5. Levels of Organization • Remember the cellular levels of organization?? • Cell  Tissue  Organ  Organ System  Individual • There are 6 levels of ecological organization: • 1. Individual • 2. Population • 3. Community • 4. Ecosystem • 5. Biome • 6. Biosphere

6. How Do I Remember Those? • Remember “My Very Educated Mother Just Served Us Nachos?” • Used by many to remember the planets • Use this to remember the 6 levels of ecological organization: • In Paris cows eat buttered bread. • I = individual, p = population, c = community, e = ecosystem, b = biome, b = biosphere

7. RA Activity • Each group will be assigned one of the levels of organization. • Group 1 – Individual/Organism • Group 2 – Population • Group 3 – Community • Group 4 – Ecosystem • Group 5 – Biome • Group 6 – Biosphere • Your group will become the expert on your assigned level and then make a poster explaining YOUR LEVEL ONLY! • We will do a gallery walk to learn about the levels; take notes as you tour the posters (a tree map would be a great way to organize your notes for this!) • Homework – create your own diagram showing each of the ecological levels of organization

8. More About the Levels • Level One: Individual – an organism • Characteristics of an individual or living thing: • Have cells • Sense and respond to change • Reproduce • Have DNA • Use energy • Grow and develop • Examples: human, giraffe, daisy, tree

9. Levels, Continued • Level Two: Population – a group of individuals of the same species living in the same geographic area • For example: humans in Avon, snapping turtles in a pond, deer in a certain forest

10. Levels, Continued • Level Three: Community – different populations that live together in the same geographic area • For example: All animals that live in Avon (mice, rabbits, dogs, cats, humans) • Level Four: Ecosystem – a collection of communities in an area plus the abiotic factors • Includes living and nonliving components • For example: Pond (H2O, fish, turtles, bacteria, plants)

11. Levels, Continued • Level Five: Biome – a group of ecosystems that have the same climate and communities present • For example: Indiana, Midwest Region, Desert • Level Six: Biosphere – the portion of the Earth in which all life exists

12. Habitats • A habitat is an area where an organism lives! • Include biotic and abiotic factors • For example: Turtle’s habitat • Abiotic factors: water, temperature, sun, mud/dirt • Biotic factors: fish, other turtles, bacteria, plants

13. Niches (rhymes with witches) • A niche is the role an organism plays in an ecosystem • Includes a full range of biotic/abiotic factors • Such as: • Living environment – Where in an ecosystem does that specific species live? • Eating – What does it eat? How does it obtain food? • Reproduction – How many mates are available? When is mating season? • Climate – Are there changes in temperature? Humidity? • Competition – With what do I have to compete for mates, food, and space?

14. Community Interactions • Organisms in a community must interact with each other to obtain food, space, mates, etc. • There are three types of community interactions: • Competition • Predation • Symbiosis

15. Competition • Competition is when organisms of the same or different species attempt to use an ecological resource at the same time. • A resource is any necessity of life. • For example: water, light, food, space • Examples of competition include: • Two crocodiles competing for a place to lay eggs • Three female songbirds competing for a male mate • Geese and ducks competing for a nest around a retention pond

16. Predation • Predation is an interaction in which one organism captures and feeds upon another • There are TWO organisms present • Predator – the organism that is KILLING and EATING • For example: tiger, anaconda, lion • Prey – the organism being eaten • For example: rabbit, mouse, antelope

17. PREDATOR: SLY FOX PREY: POOR LITTLE RABBIT

19. RA Activity • On pages 39 and 40 in your Zebra text, read all 3 types of symbiotic relationships . • Quickly summarize ALL 3 relationships on your CH 2 Notes Packet • Listen for EXAMPLES OF EACH in the “Magic School Bus” video as you do your worksheet. • Magic School Bus Symbiosis • Using the info from the video, your text, and your table partner, do a Think Aloud and summarize the three types of symbiosis at the bottom of your video worksheet.

20. Symbiosis • Symbiosis is any relationship in which two species live closely together • There are THREE types of symbiosis: • Mutualism – both organisms benefit • For example: Flowers and insects • Commensalism – one organism benefits, the other is neither harmed nor helped • For example: Birds on rhino/antelope’s backs; sharks and ramora fish; whales and barnacles • Parasitism – one organism hurts, the other benefits • For example: Tick and humans; fleas and dogs

21. Mutualism Parasitism Commensalism Commensalism

22. Section 2: Flow of Energy in an Ecosystem • All living things need energy to power every little thing they do; the flow of energy through an ecosystem is VERY important! • Things to think about: • Where does the energy for life processes come from? • How does energy flow through living systems? • How efficient is the transfer of energy among organisms in an ecosystem?

23. Producers • Producers are organisms that produce their own food • They often use sunlight /special pigments to produce food • Also known as autotrophs • Auto = self; troph = feeder • For example: plants and algae • Producers rely on two types of energy to make food: • 1) Sunlight 2) Other chemicals (chemotrophs)

24. Sunlight & Chemicals • Sunlight • Photosynthesis – when plants use sunlight, water, and carbon dioxide to make food • For example: Plants and algae • Other chemicals • Chemosynthesis – when bacteria use other chemicals to produce food because they don’t have a source of sunlight • Generally use methane or hydrogen gas • For example: bacteria at the bottom of the ocean

25. Consumers • Consumers are organisms that can’t produce their own food • Also known as heterotrophs • For example: Any animal (human, mouse, elephant) • Consumers rely on energy from the sun INDIRECTLY • They will often eat autotrophs to obtain food/energy • They often also eat other heterotrophs to obtain food/energy

26. Consumers, Continued • There are 5 types of consumers. • 1. Herbivores – animals that only eat plant material • For example: rabbits, cows, most insects • 2. Carnivores – animals that only eat meat/animals • For example: hawks, tigers, snakes

27. Consumers, Continued • 3. Omnivores – animals that eat both plants and animals • For example: Humans, black bears, crows • 4. Insectivores – these eat only insects • For example: Most reptiles and amphibians (turtles, frogs, salamanders, etc.)

28. Consumers, Continued • 5. Decomposers/detritivores – eat dead and/or rotting material • For example: Bacteria, fungi, earthworms, snails, and mites

29. Trophic Levels • Each step in a food chain or food web is called a trophic level. • 1st Level: ALWAYS producers • 2nd, 3rd, and 4th levels: ALWAYS consumers • 2nd level is always an herbivore – they eat plants/producers from level 1 • First consumer = primary consumer • Second consumer = secondary consumer • Third consumer = tertiary consumer • Fourth consumer = quaternary consumer

30. Trophic Level Examples • Food Chain: • Flower  Caterpillar  Frog  Snake  Owl • Flower = producer • Caterpillar = primary consumer • Frog = secondary consumer • Snake = tertiary consumer • Owl = quaternary consumer

31. Food Chains A food chain is a series of steps in which organisms transfer energy by eating (and being eaten). Food chains show a one-way flow of energy. They use arrows to indicate the direction of energy flow. For example: grass  rabbit  snake  owl

32. Food Chain

33. Food Web A food web is a network of complex food chain interactions. Links all food chains in an ecosystem More complex portrayal of energy flow Shows all possible food chains Fig. 14, pg. 43

34. Food Web

35. More Examples

36. Ecological Pyramids • An ecological pyramid is a diagram that shows the approximate amounts of energy/matter contained within each trophic level in a food chain or web. • The amount of energy/matter will ALWAYS decrease as you go UP the pyramid. • There are three types of ecological pyramids: • 1. Energy • 2. Biomass • 3. Numbers

37. Energy Pyramids • Energy pyramids show how much energy is transferred to each trophic level. • For example: grass  rabbit  owl • How much energy does the rabbit gets when it eats the grass? How about when the owl eats the rabbit? • Only 10% of the energy moves on to the next level! • The rest of the energy is eliminated as heat. • For example: Grass (100%)  Rabbit (10%)  Owl (1%)

39. Biomass Pyramid • A biomass pyramid shows how much biomass there is at each level. • Biomass is the amount of living tissue within a given trophic level. • Biomass is usually expressed in grams (g) or kilograms (kg) per meter2 • The greatest amount of biomass is at the bottom of the pyramid.

41. Numbers Pyramid A numbers pyramid shows how many individuals are at each trophic level. For example: blades of grass  # of rabbits  # of owls (per acre) The greatest number of individuals is at the bottom of the pyramid!

43. Section 3: Cycling of Matter • Recycling in the Biosphere • Energy flows ONE-WAY! • From: the Sun  producer  primary consumer  secondary consumer  tertiary consumer • Matter has a cyclical (circular) flow • What kind of matter can flow in a cycle? • Elements, chemical compounds • For example: water, carbon, nitrogen, phosphorus • The biogeochemical cycle is a cycle which passes matter through an ecosystem. • For example: Water cycle, nitrogen cycle

44. Recycling in the Biosphere • A nutrient that is scarce or cycles very slowly is called a limiting nutrient. • The limiting nutrients limit an ecosystem’s productivity/success. • For example: Space, water, nutrients, sunlight • Farmers often add nutrients to the soil (through the use of fertilizers) to make sure nutrients do not limit production of crops.

45. Water Cycle • All living things require water to survive • Water moves through the biosphere using the water cycle • Parts of the Water Cycle • Liquid  Gas (evaporation, etc.) • Gas  Liquid (condensation) • Solid  Liquid (melting) • Liquid  Solid (freezing) • Movement of water on land (runoff, infiltration, percolation) • ***Fig. 17 p. 46

47. Water Cycle • LIQUID  GAS • Occurs when water enters the atmosphere and changes from liquid form to gaseous form (water vapor) • 3 types • 1. Evaporation – water leaving any water body (puddle, pond, lake, etc.) • 2. Transpiration – water leaving plants (from the leaves) • 3. Perspiration – water leaving animals (through the skin/pores)

48. Water Cycle GAS  LIQUID • This occurs when water leaves the atmosphere to fall to the ground or other bodies of water • Called condensation • Gas molecules become so compacted (because there are SO many of them in the clouds) that they combine to become liquid • Then the liquid falls as precipitation • For example: Rain, sleet, snow, or hail

49. Water Cycle OTHER WATER MOVEMENTS • 3 types • 1. Runoff • Water that drains or flows, water not absorbed by soil. • Why? Because the soil/ground is saturated with water. • 2. Infiltration • When water is absorbed into the topsoil of the ground • 3. Percolation • A small amount of water will reach the depths of the ground • This water becomes ground water (which can be used in wells, etc.) • Water Cycle Video Clip