Top stories: Skin-seeing caterpillars, a climate ‘reality check,’ and why cats eat grass

These caterpillars can camouflage themselves, even when blindfolded

When most animals change color to match their surroundings, they can see what those surroundings look like. But the peppered moth caterpillar camouflages itself with its eyes closed, according to a new study. The trick? Vision-sensing genes in its skin.

Bioenergy plantations could fight climate change—but threaten food crops, U.N. panel warns

Drafters of a new U.N. climate report are calling it a “reality check” against the seductive appeal of a process called bioenergy with carbon capture and storage (BECCS). It would use crops to suck carbon dioxide from the atmosphere before burning them for fuel and depositing the carbon deep underground. One problem: Removing enough carbon to rein in global warming would take an area of land the size of India. Others: BECCS could use up scarce water, threaten food crops, and displace endangered species.

Mystery solved? Why cats eat grass

Cats do a lot of weird things. One of the biggies is eating grass, which they often throw up just a few minutes later. Now, after centuries of mystery—and disgust—scientists think they know why.

Europe’s record heat melted Swiss glaciers

The sweltering heat wave that roasted much of Europe last month has since moved north, where it’s wreaking havoc on the Greenland Ice Sheet. But while all eyes are trained on the Arctic ice, scientists are finding that Europe’s coldest places have also suffered. According to initial findings from the Swiss Glacier Monitoring Network, Swiss glaciers experienced unusually high melt rates during June and July heat waves—on the order of 800 million tons of ice.

Space telescope would turn Earth into a giant magnifying lens

When it is finished sometime next decade, Europe’s Extremely Large Telescope will be the largest in the world, with a mirror nearly 40 meters across. But one astronomer has proposed an even more powerful space telescope—the Terrascope—that would use Earth’s atmosphere as a natural lens to gather and focus light. Astronomer David Kipping of Columbia University calculates that a 1-meter space telescope, positioned beyond the moon, could use the focusing power of the ring of atmosphere around the edge of the planet to amplify the brightness of dim objects by tens of thousands of times.