Diver Susan Bird working at the bottom of Hoyo Negro, a large dome-shaped underwater cave on Mexico’s Yucatán Peninsula. She carefully brushes the human skull found at the site while her team members take detailed photographs. Photograph: Paul Nicklen/National Geographic

Cave divers have discovered one of the oldest human skeletons yet found in North America. Near perfectly preserved, the bones yielded DNA that has hel(...)

A newly hatched  loggerhead turtle on a Cyprus beach. Photograph: Reuters/Andreas Manolis

Scientists have developed a robot that mimics the movements of a newborn sea turtle as it struggles across the sand towards water. They hope th(...)