Global diversity of drought tolerance and grassland climate-change resilience

Drought reduces plant productivity, induces widespread plant mortality and limits the geographic distribution of plant species1–7. As climates warm and precipitation patterns shift in the future8,9, understanding the distribution of the diver-sity of plant drought tolerance is central to predicting future ecosystem function and resilience to climate change10–12. These questions are especially pressing for the world’s 11,000 grass species13, which dominate a large fraction of the terrestrial biosphere14, yet are poorly characterized with respect to re-sponses to drought. Here, we show that physiological drought tolerance, which varied tenfold among 426 grass species, is well distributed both climatically and phylogenetically, sug-gesting most native grasslands are likely to contain a high diversity of drought tolerance. Consequently, local species may help maintain ecosystem functioning in response to changin