Left, a fossilized thecamoebian believed to have lived 720-635 mya. Right, a specimen from a group of modern amoebozoan testate amoebae Disclaimer: AAAS and EurekAlert! are not responsible for the ...

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 ...

But while lifeless during that time, the planet was already covered by vast oceans dotted with hydrothermal vent systems that released large amounts of ferrous iron into the water. The earliest ...

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 ...

Our planet’s first known mass extinction happened about 440 million years ago. Species diversity on Earth had been increasing over a period of roughly 30 million years, but that would come to a ...

The study also provides a new approach to solving one of the biggest enduring scientific mysteries: when did plate tectonics begin?

A team of researchers at the University of Oxford have uncovered crucial evidence for the origin of water on Earth. Using a ...