For 2.5 million years, humans sustained themselves by eating plants and animals that lived and reproduced without our manipulation. That changed 10,000 years ago, when Homo sapiens began to intervene in the lives of a few plant and animal species, sparking what we now call the Agricultural Revolution. The Industrial Revolution followed some 10,000 years later, in the early 1700s, revolutionizing our eating habits yet again. Just as the Humanist religions were defining human beings as the image of god, humans started to view animals as meat machines. Farmers brought the techniques of the factory system into the slaughterhouse, dramatically increasing the number of animals they could raise and kill for food. The industrialization of agriculture has led to the practice now known as “factory farming,” a multibillion dollar industry that controls nearly a third of Earth’s land, is transforming ocean ecosystems, and produces more greenhouse gas emissions than planes, ships, trucks, cars, and all other transport combined.
