If people populated the Earth before us, would we even know? That’s the question explored by the Silurian Hypothesis — and it ...

The Sumerians created the world's first cities, developed the earliest known writing system, and laid the foundations for civilization in ancient Mesopotamia. Yet despite their enormous influence on ...

Earth is completely overrun with humans -- there are billions of us living and dying on this planet, leaving signs of our existence in the soil, atmosphere, and even in space. Are we the first, though ...