有趣的海洋生物世界-兼修英語.ppt

1、So you want to study marine biology?,有趣的海洋生物,Introduction to Marine Biology,Physical Oceanography Waves, Tides, Ocean Circulation, Seawater, and Surfing?,Introduction to Marine Biology,Marine Biology - Species Diversity,Introduction to Marine Biology,Marine Biology Habitats, Ecology, and Interaction

2、 with the environment,Introduction to Marine Biology,A few general concepts,Evolution as the unifying theory of biology,Darwins theory of evolution by natural selection:,1. Genetic variation,2. Inheritance of variation by offspring,3. Natural selection Selects for adaptations that enhance a) surviva

3、l b) reproduction,Sources of Variation?,1. Mutations most destructive, but,2. Sexual reproduction -,Introduction to Marine Biology,A few general concepts,The scientific method- How do things work?,Steps:,1. Observation,2. Hypothesis,3. Experiment,4. Conclusion,Tested hypothesis Theory!,Other things

4、to consider:,1. Controls,2. Sample sizes,Atmospheric circulation,Different parts of the earth are heated by the sun at different rates.,Equatorial regions are exposed to more direct sun light and are therefore heated more than the higher latitudes.,Atmospheric circulation,Note that the differential

5、heating of the equatorial regions relative to the poles results in the temperature difference with latitude, but does not explain “seasons”.,Seasons are a function of the tilted axis of the earth.,Atmospheric circulation,What happens to air as it heats up or cools down?,A convection current is forme

6、d.,Atmospheric circulation,Same thing happens to the earth!,Atmospheric circulation,But things are not so simple on earth the earth rotates what is the effect of the rotation?,The Coriolis Effect -,The tendency of any object moving freely across the globe to appear to curve to the right in the north

7、ern hemisphere, and to the left in the southern hemisphere.,Reason? has to do with differences in the cross-sectional circumference of the earth as a function of latitude Can you think of demonstrations to see how this might work?,Atmospheric circulation,So what is the result of the coriolis effect

8、on the atmospheric circulation of the earth?,What other factors can you think of that would influence atmospheric circulation?,Atmospheric circulation,What other factors can you think of that would influence atmospheric circulation?,There is a difference between the geographical equator and the meteorological equator. Since the meteorological equator is not constant (because of the seasons), the position of The intertropical convergence zone (ITCZ) changes,And dont forget about the potential effect of land masses, storm systems, and other factors such as volcanoes, et