He did mention in one of the planet earth 2/3 series how so much of the land is used for farmed animals. And, for the sake of completeness of argument, for restoring what was lost, the challenge is how to raise the standard of living fast enough for people so they give a damn about anything apart from ourselves was THE challenge to combat climate change and global ecological disaster. He specifically mentioned e.g. educating girls and making older-aged societies more propsperous. Prosperous people can make better choices about farmed animals as food.