Life at the start of the Ordovician remained confined to the seas ... Ordovician reefs were also home to large sea lilies, relatives of sea stars. Anchored to the bottom inside calcareous tubes ...

At least two mass extinction events in Earth's history were likely caused by the 'devastating' effects of nearby supernova explosions, a new study suggests. Researchers say these super-powerful blasts ...

At least two mass extinction events in Earth's history were likely caused by the "devastating" effects of nearby supernova ...

Most people know the theory that an asteroid smashed into Earth — hitting what is now the Yucatán Peninsula — and killed off ...

Learn how the rocks formed, take a look at the life in the ocean that covered this area 450 million years ago ... The pieces commonly found in Southwestern Ohio were formed about 450 million years ago ...

As part of this, the research team calculated the supernova rate within 20 parsecs of the Sun, or approximately 65 light-years, and compared this with the approximate rate of mass extinction events on ...