8 th Grade Ecology Changes in the Environment Study Guide

1. 8th GradeEcologyChanges in the Environment Study Guide

2. 1. Diapause Insect form of hibernation Technical Definition: A period of suspended growth or development in certain insects in response to adverse environmental conditions Example: ladybug beetles becoming dormant and over-wintering in a sheltered log-pile until spring. . Image from: http://www.glyphguy.com/blogs/2008/11/; Technical Definition: www.thefreedictionary.com; Student Definition: adapted from www.thefreedictionary.com

3. 2. Adaptation A change in an organism that enables it to survive. Technical Definition: A structure, behavior or other trait in an organism that enables it to survive in its environment. Example: A more flexible neck so the tortoise can reach more food. OR: In a saltwater bay area that gets flooded with fresh water after a rain, plants that can tolerate both salt and freshwater will survive better than those that can’t. Image from: http://www.education.com/files/25001_25100/25038/file_25038.jpg; Technical Definition: www.thefreedictionary.com; Student Definition: adapted from Access Science Glossary, page 310.

4. 3. Natural Selection Helpful traits are passed on to new generations. Only those organisms best suited to a particular environment are likely to survive. Natural selection is not a result of short-term environmental change, it happens over generations. Which fox is best suited for the environment? Technical Definition: The process by which organisms with traits best suited to an environment survive and pass their traits to the next generation more often than organisms without these traits. Images adpated from: http://www.hickerphoto.com/data/media/40/snow-white-arctic-fox_29632.jpg & http://www.arkive.org/media/6E/6E96B6F5-59DF-4B8F-91C9-A4F023ED7FBE/Presentation.Large/Arctic-fox-in-winter-coat-mouth-open.jpg; Technical Definition from: www.thefreedictionary.com; Student Definition: adapted from Access Science Glossary, pg 202.

5. 4. Long Term Environmental Changes • Long-term environmental changes are much more gradual and allow populations the opportunity to adapt. • For example, natural temperature fluctuations and cycles occur on Earth over thousands of years (Climate change). These fluctuations may cause changes to an ecosystem that are too gradual to be observed directly. Over time, populations adapt in order to better survive in their changing ecosystems. • Other Long-term changes include: Deforestation, Urbanization, Radioactive waste, Extinction.

6. 5. Long-term Human Impact • Humans can cause environmental changes through Global Warming, Deforestation, Urbanization, Building Dams, and Introduced Species, Long-term Pollution. • For example: An introduced species, like a snake, may prey on native animals, like ground nesting birds, that are unable to adapt quickly and cause the native animal to go extinct. • OR: pollution may cause mutations.

7. 6. Rainfall and Bird Beaks • In the Gizmo you did in class, longterm droughts caused plants with thick seed coats to be more likely to survive. In response, birds with strong thick bills are better able to crack the hard seeds and are more likely to survive. The birds with thick bills will be the ones to reproduce and pass the trait to the next generation.

8. 7. Short-term Environmental Changes • Short-term environmental change: environmental change that occurs quickly and affects organisms immediately. • Short-term environmental changes, like droughts, blizzard, floods, and fires, do not give populations time to adapt to the change and force them to either move (migrate) or become extinct. (Extinct species no longer exist.)

9. 8. Organisms Respond to Short-term Changes • Organisms may leave the area (for example frogs leaving a dried up creek) • Populations may be wiped out in a flood • Insects may go dormant during a sudden snow storm

10. 9. Dormancy / Hibernation • Sometimes the two terms are used interchangeably, but technically the term hibernation only applies to mammals like squirrels and mice that undergo very specific metabolic changes when they enter winter dormancy.  • Dormancy is a period in an organism'slife cycle when growth, development, and (in animals) physical activity are temporarily stopped. This minimizes cellular activity and helps an organism to conserve energy. • Dormancy tends to be closely associated withenvironmental conditions.  In addition to surviving winter, plants and animals may need to go dormant (aestivation) during hot, dry conditions as well.

11. 9.Migration Technical Definition: The seasonal movement of a complete population of animals from one area to another. The movement of animals due to the changing seasons is a long-term adaptation to the seasonal climate pattern. Animals might also migrate or move away from an area that is affected by a temporary change such as pollution, drought, fire, or other short-term natural disaster. If conditions improve, animals may quickly move back from nearby areas. If the change becomes long-term, the animals must adapt or they can no longer live there. Adaptation is a long term change. Image from: http://www.paulnoll.com/Oregon/Birds/Avian-migration-Swans.jpg; Technical Definition: www.thefreedictionary.com; Student Definition: adapted from ScienceSaurus Glossary, page 501.

12. 10. & 11. Air Pollution • Any substance that people put into the atmosphere that has damaging effects on living things and the environment is considered air pollution. • Causes: Burning fossil fuels, CFCs in refrigerants & aerosols, Sulphur dioxide in smog, smoke • Effects: Global warming due to greenhouse effect, acid rain, soot covered trees.

13. Q. 12. & 13. Runoff Pollution Runoff pollution is caused by rainfall or snowmelt moving over and through the ground. As therunoffmoves, it picks up and carries away natural and human-made pollutants, like nitrogen and phosphorus in chemical fertilizers, manure from cattle feedlots, pesticides, oils, antifreeze, and other chemicals. The contamination is finally deposited into lakes, rivers, groundwater, and oceans. Fertilizers can cause dead zones. (see next slide) Other chemicals can disrupt hormones in aquatic organisms, and cause mutations. Image adapted from: http://blog.lib.umn.edu/schne644/architecture/; Technical Definition: www.thefreedictionary.com; Student Definition: adapted from Access Science, page 106.

14. 18. & 21. Dead Zones Low-oxygen areas in the world's oceans. Excessive fertilizer (nitrogen) can cause the overgrowth of phytoplankton (algae) which then die off and use up the oxygen. This can cause dead-zones or fish kills. The Gulf of Mexico dead zone near the mouth of the Mississippi River (Photo courtesy NOAA). Image from: http://www.ens-newswire.com/ens/mar2008/2008-03-11-091.html; Definition: www.thefreedictionary.com

15. Q. 14., 15., 16. & 20. Coral Reefs • Coral reefsare underwater ecosystems with high biodiversity held together by colonies of tiny animals called polyps. Mostcoral reefs are built from stonycorals. • Corals are sensitive to water temperature, pH (ocean acidification), and excessive nutrients. Humans negatively impact corals through global warming (increased storms), CO2 pollution (dissolved acids), and fertilizer runoff. • Anartificial reef is a human-made underwater structure, typically built to promote corals and other marine life in areas with a generally featureless bottom. Artificial reefs may help to control erosion. This is generally a positive human impact on the environment.

16. Camouflage Blending into the environment Technical Definition: The concealment by disguise or protective coloring. Example: Light-colored moths against a dark tree trunk are easier to see than camouflaged dark moths against dark tree trunks. Image from: http://bp1.blogger.com/__GX3PlNzEG0/RwUFJD6a2vI/AAAAAAAAApQ/ZKrdC2t5Bxo/s1600-h/camouflaged-animals-1.jpg; Technical Definition: www.thefreedictionary.com; Student Definition: adapted from www.thefreedictionary.com

17. Biodiversity Biodiversity is the variety of life on Earth and the essential interdependence of all living things In general, the more variety or diversity in a population or ecosystem, the healthier and more stable it is. The greater the number of different kinds of organisms, the better. Biodiversity is good!