One of Earth's most consequential bursts of biodiversity—a 30-million-year period ... time, they found oxygen levels stayed relatively flat for millions of years and then rose during the Paleozoic era ...

Tomkins and his colleagues were intrigued by a window of time in the Ordovician period (~485-443 million years ago ... Earth's surface other than some of the earliest land plants. The animals of Earth ...

The world and its ecosystems have been around for a long time — so long that the first mass extinction occurred “just shy” of ...

“This mass extinction event in the Ordovician, this happened ... where most organisms lived during that time. Those factors from that period make Anticosti Island a prime location to research ...

This time was called the Cambrian Explosion. And the animals that evolved during this period had hard body parts like shells ... Earth saw its first mass extinction event. This was the ...

Ancient artifacts can tell the story of humanity and how we evolved technologically, spiritually, and emotionally. However, sometimes archaeologists find ...

Let’s start with a clear definition of what constitutes a mass extinction. Unlike regular extinctions, which occur at a steady background rate — about 10% of species lost every million years — mass ...

ISTOCK / GETTY IMAGES PLUS The researchers' idea that Earth once had rings comes from reconstructions of Earth's plate tectonics from the Ordovician period—which ran between ... the area of the Earth ...