Cheap meat, dairy, and eggs are an illusion—we pay for each with depleted forests, polluted freshwater, soil degradation, and climate change. Diet is the most critical decision we make with regard to our environmental footprint—and what we eat is a choice that most of us make every day, several times a day. Dietary choice contributes powerfully to greenhouse gas emissions (GHGE) and water pollution. Animal agriculture is responsible for an unnerving quantity of greenhouse gas emissions. Eating animal products—yogurt, ice cream, bacon, chicken salad, beef stroganoff, or cheese omelets—greatly increases an individual’s contribution to carbon dioxide, methane, and nitrous oxide emissions. Collectively, dietary choice contributes to a classic “tragedy of the commons.” Much of the atmosphere’s carbon dioxide (CO2) is absorbed by the earth’s oceans and plants, but a large proportion lingers in the atmosphere—unable to be absorbed by plants or oceans (“Effects”). Plants are not harmed by this process, but the current overabundance of carbon dioxide in the atmosphere causes acidification of the earth’s oceans. As a result of anthropogenic carbon dioxide emissions, the “acidity of the world’s ocean may increase by around 170% by the end of the century,” altering ocean ecosystems, and likely creating an ocean environment that is inhospitable for many life forms (“Expert Assessment”). Burning petroleum also leads to wars that devastate human communities and annihilate landscapes and wildlife—including endangered species and their vital habitats. Additionally, our consumption of petroleum is linked with oil spills that ravage landscapes, shorelines, and ocean habitat. Oil pipelines run through remote, fragile areas—every oil tanker represents not just the possibility but the probability of an oil spill. As reserves diminish, our quest for fossil fuels is increasingly environmentally devastating: Canada’s vast reserves of tar sands oil—though extracted, transported, and burned only with enormous costs to the environment—are next in line for extraction. Consuming animal products creates ten times more fossil fuel emission per calorie than does consuming plant foods directly (Oppenlander 18). (This is the most remarkable given that plant foods are not generally as calorically dense as animal foods.) Ranching is the greatest GHGE offender.