 So chicken stacks up pretty well against other meats. But as I've been finding out, there are huge differences in the ways that different chickens are kept. So what's the environmental difference between a high welfare bird, a long-lived, free-range bird slaughtered at, say, 16 weeks, versus an intensive bird, raised fast and killed young at five or six weeks? How do they stack up? Well, if we just forget for the moment the fact that a chicken might be a sentient being and its quality of life might matter...