Cause of global warming: greenhouse effect Primary cause of greenhouse effect: carbon dioxide emissions from fossil fuels Fossil fuels needed to produce meat-centered diet vs. a meat-free diet: 3 times more Percentage of U.S. topsoil lost to date: 75 Percentage of U.S. topsoil loss directly related to livestock raising: 85 Number of acres of U.S. forest cleared for cropland to produce meat-centered diet: 260 million Amount of meat imported to U.S. annually from Central and South America: 300,000,000 pounds Percentage of Central American children under the age of five who are undernourished: 75 Area of tropical rainforest consumed in every quarter-pound of rainforest beef: 55 square feet Current rate of species extinction due to destruction of tropical rainforests for meat grazing and other uses: 1,000 per year Source = " Diet For A New America " by John Robbins