So economically it meant more-- it made more sense to eat meat under those circumstances, but of course the meat didn't exist in all places of the world, so some people were dependent on plants.

因此,从经济角度看,在那样的环境中,食肉更加合理,当然肉类并不是世界各地到处都有,因此,有些人们就依赖于农作物

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选