Human history is littered with expired civilizations, and scholars and archaeologists have made a determined effort to understand why and how civilizations collapse. They've found that symptoms like a ...

Add Yahoo as a preferred source to see more of our stories on Google. Collage of a telescope under a starry sky and a planet in space. Earthlings, brace yourselves: the galaxy may be emptier than your ...

Across deserts, jungles, and polar ice, new discoveries are quietly stretching the story of civilization further back in time than many of us learned in school. As archaeologists debate mysterious ...