2050, to put it in brutal terms, the extra humans on the planet will weigh a little over 100 million tonnes, whereas, unless the current trend is disrupted, the extra farm animals will weigh 400 million tonnes.102 The biggest population crisis is not the growth in human numbers, but the growth in livestock numbers. This escalating pressure is caused by Bennett’s Law, which states that the consumption of fat and protein rises with people’s incomes.
