1. Ecology

2. Ecology Ecology = the study of the interactions among organisms and their environment Ecology = the study of the interactions among organisms and their environment

3. The nonliving or physical things in an environment are called ABIOTIC factors. Examples: - Sunlight - Temperature - Rainfall - Air -S-S-S-Soil -E-E-E-Earthquakes Abiotic Factors

4. Biotic Factors The living or biological things in an environment are called the biotic factors. Examples: parasitism disease predators prey competition

5. Levels of Organization Ecologists study organisms ranging from the various levels of organization: Ecologists study organisms ranging from the various levels of organization: –Species –Population –Community –Ecosystem –Biome –Biosphere

6. Species =a group of similar organisms that can breed and produce fertile offspring Species =a group of similar organisms that can breed and produce fertile offspring Levels of Organization

7. Population =group of organisms, all of the same species, which interbreed and live in the same area. EX: all the turtles in Town Lake

8. Levels of Organization Community = a collection of different populations that live together

9. Levels of Organization Ecosystem = a collection of interacting populations and their physical surroundings (abiotic factors)

10. Levels of Organization Biome = a group of ecosystems with the same climate and dominant communities Tropical rain forest Tropical dry forest Tropical savanna Temperate woodland and shrubland Desert Temperate grassland Boreal forest (Taiga) Northwestern coniferous forest Temperate forest Mountains and ice caps Tundra

11. Levels of Organization Biosphere= the part of the earth where life exists including land, water, air, and atmosphere It extends from high in the atmosphere to the bottom of the oceans. If the earth could be shrunk to the size of an apple, the biosphere would be no thicker than the apple's skin.

12. Habitat vs. Niche HABITAT Place where an organism lives Place where an organism lives Lots of organisms have the same habitat Lots of organisms have the same habitat NICHE Role and position a species has in its environment Role and position a species has in its environment Organisms want a unique niche Organisms want a unique niche

13. Habitat vs. Niche HABITAT Ex: red fox’s habitat is the forests’ edge, meadows, and river bank Ex: red fox’s habitat is the forests’ edge, meadows, and river bank NICHE Ex: red fox’s niche is a predator which feeds on the small mammals etc. that is active at night Ex: red fox’s niche is a predator which feeds on the small mammals etc. that is active at night

14. Symbiotic Relationships Symbiosis = permanent (living together) relationship between two different organisms 3 types: 1. Mutualism 2. Commensalism 3. Parasitism

15. Symbiotic Relationships 1. Mutualism = when both organisms benefit from each other EX: clownfish and sea anemone EX: lichen EX: flower and bee

16. Symbiotic Relationships 2. Commensalism = one organism benefits, the other is not helped or harmed EX: pilot fish and shark (fish eats scraps from the shark’s food)

17. Symbiotic Relationships 3. Parasitism = one organism benefits, the other is harmed EX: tapeworms EX: ticks

18. Predation Relationships Predator = an animal that feeds on another animal Predator = an animal that feeds on another animal Prey = that animal that is killed and eaten Prey = that animal that is killed and eaten EX: lion (predator) hunts and eats the zebra (prey)

19. Population Size Size of a population changes over time. Size of a population changes over time. Most populations stabilize rather than grow endlessly. Most populations stabilize rather than grow endlessly. Why? Because of demands on the ecosystem (ex. Enough food?) Why? Because of demands on the ecosystem (ex. Enough food?)

20. Limiting Factors Limiting Factors = any environmental factors that limit the size of a population Limiting Factors = any environmental factors that limit the size of a populationEX: - Availability of food - Availability of water - Availability of oxygen - Availability of sunlight

21. Density- Dependent Limiting Factors Limit the growth of a population when the pop gets to a certain size Limit the growth of a population when the pop gets to a certain size Population density = the # of organisms in a given area Population density = the # of organisms in a given area

22. Density- Dependent Limiting Factors Two Main Factors 1. Competition- when a pop gets big, organisms compete for available resources EX: group of trees fighting for sunlight, soil, or water

23. Density- Dependent Limiting Factors 2. Predation – if the predator population becomes too large, there will not be enough prey to support it

24. Density-Independent Factors Limit the growth of a population regardless of its size Limit the growth of a population regardless of its sizeEX: - Climatic events like extreme cold/heat, tidal waves, volcanoes, flooding, drought

25. Density-Independent Factors Diseases such as HIV, influenza, tuberculosis, Bubonic Plague, and etc. Diseases such as HIV, influenza, tuberculosis, Bubonic Plague, and etc. They kill humans without the care of the population. They kill humans without the care of the population.

26. Carrying Capacity Carrying capacity = the largest population that a given environment can support over a long period of time Carrying capacity = the largest population that a given environment can support over a long period of time Important for conservationists in managing wildlife pops Important for conservationists in managing wildlife pops

27. Carbon Cycle The cycling of carbon dioxide from the atmosphere through the land and back. The cycling of carbon dioxide from the atmosphere through the land and back. Processes of photosynthesis and aerobic respiration had this cycle balanced. Processes of photosynthesis and aerobic respiration had this cycle balanced. Industrial revolution brought about the burning of fossil fuels which increased the amount of CO 2 released into the atmosphere. Industrial revolution brought about the burning of fossil fuels which increased the amount of CO 2 released into the atmosphere. This excess of CO 2 (greenhouse gas) has increased the Earth’s atmospheric temperatures resulting in a climate change. This excess of CO 2 (greenhouse gas) has increased the Earth’s atmospheric temperatures resulting in a climate change.

28. Water cycle The cycling of water from the atmosphere down to Earth and back to the atmosphere. The cycling of water from the atmosphere down to Earth and back to the atmosphere. This cycle is driven by solar energy. This cycle is driven by solar energy.

29. Nitrogen Cycle The cycling of nitrogen from the Earth to the atmosphere and back. The cycling of nitrogen from the Earth to the atmosphere and back. Nitrogen cycle was in balance but the addition of fertilizers along with burning of fossil fuels has unbalanced the cycle. Nitrogen cycle was in balance but the addition of fertilizers along with burning of fossil fuels has unbalanced the cycle. Excess of nitrogen in our water systems results in eutrophication. Excess of nitrogen in our water systems results in eutrophication. Eutrophication is also known as alga blooms. It ends up killing off all the organisms in the system. Eutrophication is also known as alga blooms. It ends up killing off all the organisms in the system.

30. Oxygen Cycle The cycling of oxygen from the atmosphere through photosynthesis and aerobic respiration. The cycling of oxygen from the atmosphere through photosynthesis and aerobic respiration.

31. QUESTIONS 1. Which of the following is a symbiotic relationship where both organisms benefit? a. mutualism b. commensalism c. altruism d. competition

32. Questions 2. Which of the following pairs of animals are most likely to have a predator-prey relationship? a. dog and tapeworm b. buffalo and tickbird c. spider and fly d. whale and barnacle

33. Questions 3. Some species of shark allow small fish to enter their mouths without eating them. Inside the mouth, the small fish feed on debris around the teeth. The sharks get their teeth cleaned, which reduces the risk of decay and infection. Which term best categorizes this relationship? a. predation b. mutualism c. commensalism d. parasitism

34. Questions 4. Which of the following is a density- dependent limitation on population growth? a. wildfire b. competition c. unlimited nutrients d. severe drought

35. Questions 5. Which cycle is responsible for the increase in the Earth’s atmospheric temperatures? a. Water b. Nitrogen c. Carbon d. Oxygen