Life without light: cave creatures thrive under cover of darkness.

You won't find most inhabitants of Romania's Movile Cave anywhere else on Earth. That in itself would make the place intriguing. But now scientists have identified this extraordinary ecosystem west of the Black Sea as the first known on land to thrive without photosynthesis, the use of sunlight to make food.

"The ecosystem in Movile Cave is much more like a deep-sea vent community than that of other caves," says biologist Thomas Kane of the University of Cincinnati. Like the animals discovered clustered around hydrothermal vents on the ocean floor, the creatures of Movile Cave live in an ecosystem using hydrogen sulfide, not sunlight, as its basic energy source. …