<p> Ecosystem Unit Notes</p><p>1. Organism – any living thing (ex: 1 trout, 1 frog, 1 bear)</p><p>2. Population - group of organisms of same type of species that </p><p> live together in same area. (ex: trout in a stream; redwoods in </p><p> a forest; frogs in a pond)</p><p>3. Community - living part of any ecosystem - all the different</p><p> populations living together in an area. (ex: pond community: </p><p> has lily pads, frogs, fish, insects, cat tails, etc)</p><p>4. Ecosystems - all living and nonliving things in an area that</p><p>Interact with one another – the community and the environment.</p><p>(ex: forest, ocean, drop of water, solar system)</p><p> a. Ecosystems can be as tiny as drop pond water or a garden and as</p><p> large as ocean, forest, or planet – it’s size is defined by the person </p><p> studying it.</p><p> b. Ecosystems are not isolated; they overlap & affect one another. (ex: grizzly [forest] eats salmon</p><p>[stream]; owl [mountains] eats hare [desert], etc.) </p><p>5. Abiotic – the nonliving things in the ecosystem. (ex: dirt, water, rocks, air, temperature, humidity, etc)</p><p>6. Biotic – the living things in the ecosystem. (ex: fish, frog, lily pad, cat tails, trees, whales, insects, etc)</p><p>7. Habitat - place in which organism lives. It provides food, shelter, & other resources organisms need to</p><p> survive. Organisms protect their habitat and fight with one another for the limited resources available.</p><p> a. More than one species can share a habitat. (ex: coral reef, tropical rainforest, field, etc – Many </p><p> different plants & animals live in each of these habitats) </p><p> b. More than one species can share similar habitats and food. (ex: shark and dolphin live in the same</p><p> habitat and eat similar food.)</p><p>8. A niche includes everything the organism does and everything it needs in the environment - place to live,</p><p> food, predators, other organisms around it, light, humidity, temperature, etc.)</p><p> a. Organisms can have more than one name to their niche. (ex: lion is a predator, consumer, and a</p><p> carnivore; a rabbit is a consumer, prey, herbivore, etc) b. Two species CAN NOT share the same niche. Over time, one species will die off because there </p><p> will not be enough for it to survive.</p><p>Energy Flow through the Ecosystem</p><p>9. Food chains, food webs, & energy pyramids show the FLOW OF ENERGY, not what eats what. </p><p>ARROWS POINT TO WHO GETS THE ENERGY.</p><p>10. Producer – makes its own energy through photosynthesis (ex: tree, grass, flower) – always at the </p><p> beginning of all food chains, webs, & pyramids. PHOTOSYNTHESIS IS THE FOUNDATION or </p><p>BASIS FOR ALL FOOD CHAINS, FOOD WEBS, and ENERGY PYRAMIDS.</p><p>11. Consumer – must eat to get the energy it needs to survive (ex: cow, human, bat, mouse, lion, frog) – </p><p> can’t make its own food through photosynthesis.</p><p>12. Herbivore – type of consumer that only eats plants. (ex: cow, horse, rabbit, grasshopper, elephant)</p><p>13. Omnivore – type of consumer that eats both plants and other animals. (ex: humans, bears, monkeys)</p><p>14. Carnivore – type of consumer that only eats other animals. (ex: owl, lion, frog, wolf, eagle, blue shark)</p><p>15. Decomposer – type of consumer that breaks down dead organisms and returns the nutrients to the soil.</p><p>(ex: earthworm, ant, mushroom, bacteria) – always last in the food chains and webs because they return</p><p> the nutrients to the producers completing the cycle.</p><p>16. Scavenger – type of consumer that eats dead, dying, injured, old, young, and other easy prey. (ex: </p><p> coyote, buzzards, hyenas)</p><p>17. 1 st order consumer/1 st level consumer – first consumer in food chain, web, or pyramid – a herbivore.</p><p>18. 2 nd order consumer/2 nd level consumer – second consumer in food chain, web, or pyramid – eats other</p><p> animals – either an omnivore or carnivore.</p><p>19. 3 rd order consumer/3 rd level consumer – third consumer in food chain, web, or pyramid – eats other </p><p> animals – either an omnivore or carnivore. Changes in a Population</p><p>20. Populations will INCREASE when: more births than deaths, more immigration </p><p>(moving in) then emigration (moving out), decrease in predators or competitors,</p><p> increase in food or prey, increase in habitat or territory, decrease in hunting by</p><p> humans, decrease in habitat destruction or pollution</p><p>21. Populations will DECREASE when: more deaths than births, more emigration </p><p>(moving out) then immigration (moving in), increase in predators or</p><p> competitors, decrease in food or prey, decrease in habitat or territory, disease </p><p> or natural disaster, increase in hunting by humans, increase in habitat destruction</p><p> or pollution</p><p>22. Limiting factors prevent population from growing beyond a certain point.</p><p>(ex: amount of food/prey available, amount of habitat/territory, weather conditions</p><p>– too cold / hot / wet / dry, predators, competitors, pollution, etc.</p><p>23. Carrying capacity is the maximum amount of a population an environment can hold – when the </p><p> population reaches this point there is no more food / space available and the population begins to starve. </p><p>Population numbers cannot increase beyond this point and stay.</p><p>Behaviors that Change a Population Size 24. Predator – animal that hunts down, kills, & eats another animal for its energy.</p><p>(ex: giant sea bass catching & eating a smaller fish; smaller fish hunting down and eating a sea urchin)</p><p>– herbivores can’t be predators</p><p>25. Prey – animal that is hunted down and eaten by another animal. (ex: the smaller fish that is eaten by the </p><p> giant sea bass; the sea urchin that is eaten by the smaller fish) - producers can’t be prey</p><p>26. Competitor – an organism that competes with another organism for a resource (food, water, shelter, etc) </p><p> or mate - can be two organisms in the same species or in different species. (ex: two lions competing for </p><p> a mate; a rabbit and mouse competing for the same shelter) – organisms at the same level in a food web </p><p> or energy pyramid compete with each other.</p><p>27. Symbiosis – close relationship between 2 different species of organisms where 1 organism lives near,</p><p> on, or inside the other and at least 1 organism is helped.</p><p>28. Commensalism – symbiosis where 1 organism is helped and the other isn’t helped or harmed – it </p><p> couldn’t care less about that animal being there. Examples: osprey hawk and the wren (little bird) or the </p><p> red-tailed hawk and the saguaro cactus.</p><p>29. Mutualism – symbiosis where both organisms are helped – two different species. Examples: algae and </p><p> coral, sea anemone and clown fish, blind person and seeing-eye dog.</p><p>30. Parasitism – symbiosis where 1 organism is helped and the other is harmed. Examples: tick and dog, </p><p> leech and human, tapeworm and dog.</p><p>31. Cooperation – two or more organisms OF THE SAME SPECIES working together to get what’s</p><p> needed. (ex: wolves hunt in a pack, bees taking care of the babies together)</p>