A sustainable strategy to nourish the planet and its people must also promote biodiversity conservation. This strategy will have to include reduction in land degradation and unsustainable overuse of fertilisers, pesticides, fungicides, herbicides, and irrigation water. A case can be made for conserving biodiversity as a source of traits for incorporation, by different genetic tools, into food plants and animals, but an even stronger case can be made for a conserved biodiversity to supply ecosystem services that will nourish the planet and its occupants into the future. Biodiversity is under severe threat from many angles. One of the best ways to promote biodiversity is to preserve native habitats. By maintaining or even increasing yields on existing land, biotechnology crops can help to minimise expansion of agriculture into natural areas. It has also been estimated that agricultural biotechnology has changed pesticide spraying so as to greatly reduce greenhouse gas emissions and decrease environmental impacts of insecticides and herbicides. Gene flow from cultivated, including biotechnology-based, crops to and from wild plants is known to occur. The consequences of this flow vary from species to species, but as a general rule, do not pose a significant threat to biodiversity.