Around three quarters of the crop types grown for human food benefit from animal pollination, though they account for a much smaller share of the calories eaten, since wheat, rice and maize are pollinated by wind. What pollinators supply is largely the variety in a diet: fruit, nuts, coffee, and most vegetables grown for seed. A world without them would not starve, but it would eat a monotonous and less nutritious diet, which is a different kind of loss. Estimates of what pollination is worth vary widely for exactly this reason.