Feeding a growing population in a hotter world will require exploiting a far broader range of crop diversity than now — and that means valuing wild genes.

Over much of the world, the growing season of 2050 will probably be warmer than the hottest of recent years, with more variable rainfall. If we continue to grow the same crops in the same way, climate change will contribute to yield declines in many places. With potentially less food to feed more people, we have no choice but to adapt agriculture to the new conditions.

To some extent, adaptation can be done by moving crops to more favourable areas and by agronomic tweaks. But that will almost certainly not be enough. We will have to give crops a genetic helping hand, infusing them with new genes to allow them to better cope with new climates, and the new pests and diseases they will bring. Where are these genes going to come from?