If you’ve been thinking “At least cactus will flourish,” think again.

[E]ven these prickly survivors may be reaching their limits as the planet grows hotter and drier over the coming decades, according to research published on Thursday. The study estimates that, by midcentury, global warming could put 60 percent of cactus species at greater risk of extinction.

There’s nothing surprising in that really. Being adapted to the climate of Arizona doesn’t mean you’re adapted to the climate of a furnace.

Most cactus species “are in some way adapted to the climates and the environments that they live in,” said Michiel Pillet, a doctoral student in ecology and evolutionary biology at the University of Arizona who led the new study, which was published in the journal Nature Plants. “Even a slight change may be too much for them to adapt over shorter time scales.”

Adaptation can be fussy that way. “I didn’t say any old amount of heat, I said this heat right here.”

“It’s a popular image of cacti,” said David G. Williams, a professor of botany at the University of Wyoming who was not involved in the new research. “‘Ah, we don’t have to worry about cacti. Look at them, they’ve got spines, they grow in this terrible environment.’” But cactuses, like most plants, exist in delicate balance with the ecosystems around them, he said. “There are a lot of these tipping points and thresholds and interactions that are very fragile and responsive to changes in the environment, land use and climate change.”

…

Brazil is a hot spot for cactus diversity. As the country’s northeastern drylands experience hotter temperatures, more intense droughts and desertification, that plant wealth is in jeopardy, said Arnóbio de Mendonça, a climate and biodiversity researcher at the National Institute for Space Research in Brazil who did not work on the new study.

“Species either adapt or they will go extinct,” he said. “As adaptation is a slow process and current climate change is occurring rapidly, it is likely that many species will be lost.”

Don’t look up.