Tom Philpott, "New Research: Synthetic Nitrogen Destroys Soil Carbon, Undermines Soil Health," Grist, February 24, 2010, http://grist.org/article/2010-02-23-new-research-synthetic-nitrogen-destroys-soil-carbon-undermines/.

286 by pushing subsistence farmers to clear more forests

David Lapola et al., "Indirect Land-Use Changes Can Overcome Carbon Savings from Biofuels in Brazil," Proceedings of the National Academy of Sciences, January 2010.

287 have proven that a.s.sumption to be wrong

Claude Mandil and Adnan Shihab-Eldin, International Energy Forum, "a.s.sessment of Biofuels: Potential and Limitations," February 2010, http://www.ief.org/news/news-details.aspx?nid=311.

288 20 to 50 percent of all living species on Earth within this century

Nicholas Stern, The Economics of Climate Change.

289 Approximately one third of all amphibian species

Camila Ruz, "Amphibians Facing 'Terrifying' Rate of Extinction," Guardian, November 2011.

290 hit by a spreading fungal disease

Mich.e.l.le Nijhuis, "A Rise in Fungal Diseases Is Taking Growing Toll on Wildlife," Yale Environment 360, October 24, 2011.

291 the encroachment of human activities

Owen Clyke, "The Militarization of Africa's Animal Poachers," Atlantic, July 31, 2012; David Braun, "Human Encroachment Threatens Thousands of Gorillas in African Swamp," National Geographic, November 24, 2009; Yaa Ntiamoa-Baidu, United Nations Food and Agriculture Organization, "West African Wildlife: A Resource in Jeopardy," 1998, http://www.fao.org/docrep/s2850e/s2850e05.htm.

292 caused by a large asteroid crashing into the Earth

Anthony Barnosky et al., "Has the Earth's Sixth Ma.s.s Extinction Already Arrived?," Nature, March 2011.

293 "precipitated entirely by man"

Richard Leakey and Roger Lewin, The Sixth Extinction: Patterns of Life and the Future of Humankind (New York: Anchor Books, 1995), p. 235.

294 average 3.8 miles per decade toward the poles

Camille Parmesan and Gary Yohe, "A Globally Coherent Fingerprint of Climate Change Impacts Across Natural Systems," Nature, January 2003.

295 half of the mountain species had moved, on average

Craig Moritz et al., "Impact of a Century of Climate Change on Small-Mammal Communities in Yosemite National Park, USA," Science, October 2008.

296 reach the poles and the mountaintops and can go no farther

Elisabeth Rosenthal, "Climate Threatens Birds from Tropics to Mountaintops," New York Times, January 21, 2011.

297 at risk because they cannot adapt to climate change quickly enough

Kai Zhu et al., "Failure to Migrate: Lack of Tree Range Expansion in Response to Climate Change," Global Change Biology 18 (November 2011).

298 according to scientists, are facing a rising risk of extinction

Lucas Joppa et al., "How Many Species of Flowering Plants Are There?," Proceedings of the Royal Society B, July 2010.

299 United Nations Convention on Biological Diversity notes

United Nations Convention on Biological Diversity, "Global Biodiversity Outlook 3," January 2010, http://www.unep-wcmc.org/gbo-3_90.html, p. 51.

300 as a precautionary measure for the future of mankind

John Roach, " 'Doomsday' Vault Will End Crop Extinction, Expert Says," National Geographic, December 27, 2007.

301 carbon tax to the taxpayers but would have applied one third

Matt Kasper, "Rep. Jim McDermott Introduces Carbon Tax Law," August 6, 2012, ClimateProgress, http://thinkprogress.org/climate/2012/08/06/641831/rep-jim-mcdermott-introduces-carbon-tax-law/.