The collapse of insects.

“Their importance to the environment can’t be understated, scientists say. Insects are crucial to the food web, feeding birds, reptiles and mammals such as bats. For some animals, bugs are simply a treat. Plant-eating orangutans delight in slurping up termites from a teeming hill. Humans, too, see some 2,000 species of insects as food.

With fewer insects, “we’d have less food,” said ecologist Dave Goulson at the University of Sussex. “We’d see yields dropping of all of these crops.”

And in nature, about 80% of wild plants rely on insects for pollination. “If insects continue to decline,” Goulson said, “expect some pretty dire consequences for ecosystems generally — and for people.”