Coffee growers in Costa Rica have increased their coffee yields by leaving patches of surrounding rainforest untouched. Researchers discovered that leaving segments of rainforest in their natural state boosted bird biodiversity. Those birds fed on the borer beetle, an aggressive coffee bean pest. This model was shown to improve coffee bean yields by hundreds of dollars per hectare. The study is the first to put a monetary value on the pest control benefits rainforest can provide to agriculture. Read more at Stanford University