Global warming could rapidly reduce the cultivation of wheat and rice, threatening the production of breakfast cereals along with half of all the calories consumed by humans.
A study looking ahead to 2070 found that climate change was occurring 5,000 times faster than certain grasses can adapt, New Scientist reported.
Wheat, rice, maize, rye, barley and sorghum are all edible grasses that yield nutritious grains. In many parts of the world and throughout history, wheat or rice famines have led to widespread starvation.
The research examined how 236 grass species could adapt to the local environments they depended on for survival.
Experts predict evolutionary adaptation seems particularly unlikely for domesticated species and the result will be devastating for some human populations.