Gorillas often get a bad rap, but folks who work with them say they're as much gentle as giant. On a recent trip to scope out the primates, an NPR producer trekked into the Virunga mountains of East Africa, where more than half of the world's mountain gorillas live.

The depths of our oceans are dark, punishingly cold and utterly devoid of life. Or so scientists thought, until a team of researchers in the late 1970s stumbled upon squishy, rubbery worms, up to 7 feet long, living 8,000 feet below the surface of the Pacific.