Ecology Unit

1. Ecology Unit

2. 2.1 Organisms & Their Environment • Ecology • What does –ology mean on the end of any word? The study of • What word does eco- remind you of? Ecosystem Definition:Ecology is the study of how organisms interact with each other and their environment.

3. The environment has abiotic and biotic factors. Remember: The prefix a- in front of any word means no or not. The prefix bio- mean life or living Definitions: Abiotic factors – nonliving things in the environment. Biotic factors – living things in the environment.

4. Air Cat Temperature Moisture Plant Mushroom Light Soil Water Seeds Abiotic Biotic Abiotic Abiotic Biotic Biotic Abiotic Abiotic Abiotic Biotic Label the following items as biotic or abiotic.

5. Circle the biotic factor(s) and underline the abiotic factor(s) in the following studies: • Example #1 – Study of the life cycle of trout to observe whether they need to lay their eggs on rocky bottomed streams or sandy bottom streams. • Example #2 – Study of moles and observe which soil types the animals prefer to dig their tunnels in.

6. Levels of Organization(smallest to largest) 1. Organism – an individual living thing 2. Population – a group of organism (all of one species) that breed with each other & live in the same place. 3. Community (or Biological Community) – all populations of different species that live in the same place.

7. 4. Ecosystem – all the biotic & abitoic factors that interact with each other in a given area. Two major types of ecosystems: • Terrestrial – ecosystems located on land • Aquatic - ecosystems located in fresh or salt water Definitions: Habitat – a place where an organism lives its life - can change or disappear - example: a tree, ocean, soil, pond Niche (neesh) – how organisms interact with their biotic and abiotic parts of the habitat

8. It is an advantage for a species to occupy a niche different from other species in the same habitat. Two species can’t exist for long in the same community of their niches are the same (leads to competition & reduces resources such as food).

9. 5. Biosphere – the portion of Earth that supports life

10. www.chesterfield.k12.sc.us/.../BiologyICP.htmlRemove frame www.ux1.eiu.edu/~cfruf/bio3002/levels_ecology.htm

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12. Do all organisms get along with each other? • How organisms live together in an ecosystem is called symbiosis. • There are 3 types of symbiosis: • Mutualism • Commensalism • Parasitism

13. Mutualism • Both species benefit from each other. • Example – ants and acacia trees • Ants protect the acacia tree from other animals that might eat the tree. The tree provides nectar and a home for the ant. They both benefit from each other!

14. Commensalism • One species benefits and the other species is neither harmed nor benefited. • Example – Spanish moss growing on trees • Spanish moss has a place to live on the trees but the trees are not harmed by the moss or get nutrients from the moss. Only one benefits and the other does not.

15. Parasitism • One species benefits at the expense of another species. • Parasites usually don’t kill their host (the animal they live on). Why would you kill the person that is providing you food & a home??? • Example – ticks on a dog • Tick is a parasite that feeds off the nutrients in the dog’s blood. The dog doesn’t get the nutrients so it is harmed. • Tapeworm & roundworms work the same way as tick but they are inside the host’s body.

16. Predator – Prey relationship • Predator – found in all ecosystems and eat plants and/or animals. Predators are a type of consumer that seek out and eat other organisms. • Prey – the animal that the predator eats. • Example – cat & mouse; lion & antelope

17. Section 2.2 Nutrition & Energy Flow In order to be living, one of the characteristics of life is to use energy. How is that energy obtained by organisms? It varies on the organism. • Autotrophs – make their own food • Autotrophs are called producers. Think about the definition! Autotrophs produce their own food so called producers. • Example – grass, trees, green algae which is a unicellular organism

18. Heterotroph – can not make their own food; instead have to eat food to get energy. • Heterotrophs are called consumers. Think about the definition! Heterotrophs consume food so called consumers. • Example – deer eating leaves; bison eats grass; owl eats a mouse

19. Heterotroph Relationships: • Herbivore – consumers (heterotrophs) that eat producers (autotrophs) Example – rabbits, grasshoppers, beavers, squirrels, bees, elephants, bats 2. Carnivores – consumers (heterotrophs) eat consumers (heterotrophs) Example – lion kills another lion 3. Omnivores – consumers (heterotrophs) that eat a variety of foods (plant or animal) Example – raccoons, opossum, bears, humans

20. 4. Others Scavengers – do not kill for food; eat animals that are already dead Example - vultures Decomposers – break down dead decaying plants and animals. Example – bacteria & fungi

21. Flow of Matter & Energy • Food Chain is a simple model that shows how matter & energy moves through an ecosystem. • Arrows indicate the direction in which energy is transferred from one organism to the next. Example – Berries (autotroph) Mice (first order heterotroph)  Hawk (second order heterotroph

22. http://www.umaine.edu/umext/earthconnections/images/foodchain.gifhttp://www.umaine.edu/umext/earthconnections/images/foodchain.gif http://kentsimmons.uwinnipeg.ca/16cm05/1116/53-10-FoodChains-L.jpg http://www.bcgrasslands.org/SiteCM/i/upload/4D9BB688B89B4092F9D10BDAEF83EC41E762FBDB.jpg

23. Trophic level – a feeding step in the passage of energy & materials • First order heterotroph – organism that feeds on plants • Second order heterotroph – organism that feeds on a first order heterotroph

24. http://www.utc.edu/Faculty/Deborah-McAllister/educ575/wq04MichaelKavur/image002.jpghttp://www.utc.edu/Faculty/Deborah-McAllister/educ575/wq04MichaelKavur/image002.jpg http://www.mlms.logan.k12.ut.us/~mlowe/EnergyPyramid.gif

25. Food webs – show many food chains that can occur in a community. • Ecological pyramids show how energy flows through an ecosystem in a pyramid form. • Base is always the autotrophs (first trophic level). • Next layers build upon each layer for higher trophic levels.

26. http://cmore.soest.hawaii.edu/cruises/operex/images/terrestrial_food_web_full.jpghttp://cmore.soest.hawaii.edu/cruises/operex/images/terrestrial_food_web_full.jpg

27. 3.1 Communities • Various combinations of abiotic and biotic factors interact in different places around the world which results in conditions in one part of the world are suitable or certain life and not others. • Limiting factors – any biotic or abiotic factor that restricts (or limits) the existence, numbers, reproduction, or distribution, or distribution of organisms.

28. Examples of limiting factors: • Availability of water & food would affect how many, if any, organisms can live in an area • Predators to an area would affect the number of organisms (prey) living in the area • Temperature of the area affect which animals live there (polar bear will not be in a desert) List of common limiting factors: amount of sunlight, climate, temperature, water, nutrients/food, fire, soil, chemistry, space, other organisms

29. Factors that limit one population in a community may also have an indirect effect on another population. • Example – lack of water limits the growth of grass  lack of grass limits the seeds produced  lack of seeds limits the mouse population  lack of mice limits the hawk population • Tolerance – ability of an organism to withstand many biotic and abiotic factors. • Different species have different ranges of tolerance

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31. Succession • Natural changes & species replacements that take place in the community of an ecosystem. • Occurs in stages and at each stage different species of plants and animals may be present • At each stage of succession, new organisms may move in, others may die or move out • Difficult to observe because takes decades or more to go to the next stage • Two types of succession: Primary & Secondary

32. Primary Succession • Colonization of barren land by communities of organisms. • Takes place in land where nothing lived before Example – after a volcano • First species to grow in the area are called pioneer species Example - lichens LICHENS http://botit.botany.wisc.edu/images/332/Lichens/Foliose_lichens_130_d.gif

33. Pioneer species eventually die making the first stage of soil for other organisms to live Example – small ferns, fungi, & insects • These organisms die & more soil builds. Seeds carried or blown in will start to grow • After time, the are will become more stable. A stable, mature community that undergoes little or no change is called a climax community. • Can last 100’s of years • Change DOES occur in a community but changes are balanced.

34. http://www.life.illinois.edu/bio100/lectures/s97lects/05Succession/rockSuccession.GIFhttp://www.life.illinois.edu/bio100/lectures/s97lects/05Succession/rockSuccession.GIF

35. Volcanic Eruption Primary Succession Secondary Succession http://tinyurl.com/y95bfk9

36. Secondary Succession • The sequence of changes that takes place after an existing community is severely disrupted in some way Example – forest fire, field is not replanted, tear down a building and leave it • Are gradually changed over time • Soil already exists in a secondary succession so takes less time than primary succession to reach a climax community.

37. Years after a forest fire. http://www.ck12.org/ck12/images?id=113572

38. Stages of secondary successsion http://images.google.com/imgres?imgurl=http://biology.clc.uc.edu/graphics/bio303/wetland.jpg&imgrefurl=http://biology.clc.uc.edu/Courses/bio303/succession.htm&usg=__Q0_2nL72qKCEi_kxV7HCsux1_NM=&h=300&w=571&sz=126&hl=en&start=16&tbnid=IPIoNmJGqcPCQM:&tbnh=70&tbnw=134&prev=/images%3Fq%3Dstages%2Bof%2Bsecondary%2Bsuccession%26gbv%3D2%26hl%3Den

39. Chapter 4 Population Biology Section 4.1 Population Dynamics Principles of Population Growth • Populations typically form a “J” shape curve This “J” shaped curve is called Exponential Growth – means that as a population gets larger, it also grows at a faster rate. http://peer.tamu.edu/curriculum_modules/ecosystems/images/exponential.jpg

40. Initial increase in the number of organisms is slow because of the number of reproducing organisms is small. • Rate of growth will increase because number of individuals able to reproduce has increased. • Can a population grow indefinitely (meaning forever)? NO • Populations have limiting factors! See Chapt. 3 for the list of limiting factors. Because of these limiting factors the population may form an “S” shape growth curve.

41. Carrying capacity – number of organisms of one species that an environment can support indefinitely (forever). http://www.saburchill.com/IBbiology/images/140106009.jpg

42. Questions • What happens to a population when there are more births than deaths? • What happens to a population when there are more deaths than births? • What happens to a population when the number of deaths equal (or close to equal) the number of births? • When the population overshoots the carrying capacity, the ________ take over to bring the population into check. • Why can a population fluctuate (go up and down) once it reaches carrying capacity?

43. Answers • Increases • Decreases • Stays the same • Limiting factors • The population can go up and the limiting factors take over and bring it back down into check. The population can go down and the amount of resources (food) goes up and the population will go up.

44. Reproduction Patterns • Life–history pattern – an organism’s reproductive pattern • Can be studied by population biologists to determine if carrying capacity has been reached • Two types of reproductive patterns: • Rapid life history pattern • Slow life history pattern

45. Rapid Life History Pattern • Meaning the organism can reproduce rapidly • Typically increase rapidly & then declines when environmental conditions change Example-mosquitoes grow and reproduce quickly in the summer but not in the winter. • Usually have: • Small body size • Mature rapidly • Reproduce early • Have a short life span

46. Slow Life History Pattern • Meaning the organism reproduces slowly • Typically live in a more stable environment • Opposite of all the things listed in rapid life history patterns • Maintain population sizes at or near carrying capacity • Example – elephants, bears, whales, humans

47. 3 Ways Organisms Are Dispersed 1. Random – often seen (ex. Dandelions) 2. Clumped – most common 3. Uniform – least common (visible with birds on a wire) Uniform

48. There are 2 kinds of limiting factors when it comes to dispersal: Density-dependent factors – include disease, competition, predators, parasites, & food -these factors have an increasing effect as the population increases Density-Independent factors – mostly abiotic factors like volcanic eruptions, temperature, storms, floods, droughts -all populations can be affected by these factors, small organisms are most vulnerable

49. What can limit a population size? 1 – Predation affects population size. • If number of predators decrease then the number of prey increases • If number of prey increases then the number of predators will increase over time & then eventually will decrease because to many predators for the amount of food available.

50. What can limit a population size? 2 – Competition within a population • When resources (food, water, shelter) are plentiful, the population will increase • But when resources are not plentiful, competition will occur or those resources & the population will decrease