and travel back to 750 million years ago ... around 240 million years ago. On the Ancient Earth map, you can see the full outline of what will be the U.S. inside that supercontinent.

A bout 250 million years ago, Earth faced its greatest catastrophe. The End-Permian Event wiped out more than 80% of ocean ...

A day on Earth was just 23.5 hours long, 70 million years ago. Researchers discovered this by studying the growth rings of ancient mollusk fossils. The findings could tell us more about or planet ...

Life on Earth might have started billions of years ago on land, not in the sea ... moves back evidence of life on land by 580 million years. And not only that, it hints at the possibility that ...

Dinosaurs are the extinct relatives of birds that roamed the lands and seas of ancient Earth. They first appeared around 240 million to 230 million years ago in the Triassic Period, and went ...

No, the whole earth — including the oceans — froze ... bottoms of long-vanished oceans between 550 million and 750 million years ago. Layers of jumbled rocks (presumably brought there by ...

Learn about the time period that took place 251 to 199 million years ago. 3 min read The start of the Triassic period (and the Mesozoic era) was a desolate time in Earth's history. Something—a ...

About 800 million years ago, oxygen levels reached about 21 percent and began to breathe life into more complex organisms. The oxygen-rich ozone layer was also established, shielding the Earth's ...

A crater at the edge of the Yucatán peninsula in Mexico was created by a massive asteroid that hit Earth 66 million years ago At the end of the Cretaceous Period 66 million years ago, an ...

Our solar system's journey around the center of the Milky Way takes it through varying galactic environments, and one may have had a lasting impact on Earth's climate, according to a new study.