Precariously balanced rocks, or PBRs, record a history of things that haven't happened We've all seen them; we've even taken pictures of ourselves pretending to hold them up or to push them over.

They look like you could blow them over with a sneeze. Across the world, thousands of "precariously balanced rocks" are perched in strange positions, poised to topple. Once they would have been ...

A chilling new report from the world’s top climate scientists has delivered a stark warning, Earth's "vital signs" have reached a breaking point, with the future of humanity precariously hanging ...