ABSTRACT: IN THE early 1970s Asia’s rice farmers faced ruin. The brown planthopper, an insect up till then found mostly in Japan, began to appear across the region. It fed on young plants and transmitted grassy stunt virus, causing crops to shrivel and brown. As it swept through Asia’s paddy fields, yields crashed. By the end of the decade it had caused damage costing over $300m—more than $1 billion in today’s money.