About 252 million years ago, upward of 80% of all marine species vanished during the end-Permian mass extinction ... in Earth and planetary sciences, offered a modern analogy with land animals ...

The calculations suggested 2.5 supernovas might affect Earth in some way every 1 billion years, equating to one ... a mass extinction. During the Devonian geological era, life thrived on land ...

Dino-killing asteroidCelestial events have triggered at least one mass extinction, according to scientific evidence. A city-size asteroid slammed into Earth off ... water and land over a ...

This realization led Wright and his co-authors to connect the cosmic phenomenon with mass extinctions on Earth. Cataclysmic events have taken place five times in the past 500 million years, killing ...