Ocean acidification may ground swimming skates

 The more carbon dioxide people pump into Earth’s atmosphere, warming the planet, the more carbon dioxide and heat slip into the oceans. Warmer and more acidic water is thinning the shells of oysters. But they aren’t the only ocean dwellers facing unwanted home renovations. Anything with a shell is at risk. So, too, may be certain fish. A new study finds that as seawater becomes more acidic, the skeleton of a fish called the little skate stiffens in some places — and gets bendier in others. That could leave this fish better built for walking than swimming.