How do we achieve food security for a global population now over 7 billion people and trending towards 10 billion by 2050? This study of the global dairy industry examines how to balance our needs with those of animals and the environment. It scrutinises ruminant bovines’ worrying exhaling of methane, a greenhouse gas which, fortunately, evidence shows can be reduced by adding seaweed to cattle feed. Are the multi-thousand-cow mega-dairies of the USA appropriate models for Africa and Asia's high-growth dairy regions, where so many women are smallholders? Is it ethical to keep cows in...