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November 18, 2009. How to Make Pumpkins Fly "It's a redneck thang. You wouldn't understood." . Reading Ch. 13 YES, there is class on FRIDAY.
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November 18, 2009 How to Make Pumpkins Fly "It's a redneck thang. You wouldn't understood." • Reading Ch. 13 • YES, there is class on FRIDAY (Nov. 14) -- Start with one delightfully warped science project contest for grown-ups. Add a touch of county fair and a whole lot of tailgating. What do you get? Flying pumpkins. Every year on the first weekend after Halloween, competitors bring catapults, trebuchets, air cannons and all sorts of other pumpkin-launching contraptions to a vast cornfield near Bridgeville, Del. The World Championship Punkin Chunkin draws fans from all over the country to rural Sussex County, where a pumpkin is a "punkin" and "chunkin" rolls off the tongue so much easier than "chucking" after "punkin." This year, there were 109 machines in the competition, and 70,000 spectators.
Permian Mass Extinction (251mya) • Devastated 90-95% all species • < 5% sea life survived • ~1/3 of large land animals survived • Trees almost obliterated http://evolution-textbook.org/content/free/figures/ch10.html http://ngm.nationalgeographic.com/ngm/0009/feature4/index.html
Proposed Causes • Global cooling? • Caused other extinctions • Reduced marine habitats • Support • Pangaea formation • Glaciers at poles • Siberian traps • Flood basalts • Likely cause? • Probably not • mid-Permian cooling • Climate instability http://www.emporia.edu/earthsci/student/kaczor1/rk.htm http://earthobservatory.nasa.gov/Features/SiberiaBlog2008/page9.php
Proposed Causes • Volcanic activity • Ash would block sunlight • Acid rain generation, followed by greenhouse • Support • Siberian traps • Asteroid impact • Support • Possible impact crater • Anarctica http://researchnews.osu.edu/archive/erthboom.htm http://science.nasa.gov/headlines/y2002/28jan_extinction.htm http://earthsci.org/fossils/space/craters/permian/permian.html http://www.scientificamerican.com/article.cfm?id=geologists-link-the-great
Proposed Causes • Ocean anoxia • Oxidation of organic matter • Created dead zones • Bicarbonate burp • CO2 upwelling • Sulfide production • Phototroph blooms • fed by nutrient input from eroding land • Chlorobium (GSB) http://www.msnbc.msn.com/id/30563213/ http://www.bio.ku.dk/nuf/projects/index.htm http://waterresearch.blogspot.com/2007/06/bule-green-algae-bloom-in-dianchi-lake.html