Archaeologists have long known that complex societies can rise, flourish and then disappear so completely that only scattered ruins hint at what was lost. Now a new wave of research is sharpening the ...

Introduction : our cultural Amnesia -- Adena, first civilizers of North America -- Who were the Adena? -- The keltic fingerprint on prehistoric America -- Hopewell masters of ceremony -- Who were the ...

Earthlings, brace yourselves: the galaxy may be emptier than your last Tinder date. According to a new study, any alien civilizations out there? Probably short-lived — and doomed to fail spectacularly ...