Erin from Scotland had already switched to a completely plant-based diet when she asked Bill Nye on the Big Think to explain the science behind her decision to go vegan.

"I went vegan after watching documentaries like 'Before the Flood' and 'Cowspiracy,'" Erin said, but she questioned conflicting reports on the amount of global emissions caused by animal agriculture.

Nye explained that it can be difficult to peg the exact amount of greenhouse gases that come from cows, sheep and goats. However, he said that as the human population has surged along with the number of animals raised for food, "it's very reasonable that we're creating a tremendous amount of extra methane that wouldn't otherwise be there in the atmosphere, and that is causing global warming and climate change to happen more rapidly than [it] would otherwise."

Nye said that his diet "is becoming increasingly vegetarian," and might soon be following her lead.



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