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Mass extinctions of land-dwelling animals, including amphibians, reptiles, mammals, and birds, occur once every 27 million years, according to a new study. US researchers performed statistical ...

Five times in our planet's history, adverse conditions have extinguished most of life. Now, scientists say, life on Earth could be in trouble again, with some even saying we could be entering a sixth ...

From the Ordovician period to present day where we may be experiencing a sixth mass extinction, here are the mass extinctions that repeatedly wiped out life on Earth. Congratulations, you’re part of ...

The worst mass extinction event in the history of the Earth, 252 million years ago, took ten times longer on land than it did in the water, according to a new study. Known as the End-Permian mass ...

What is a mass extinction? Extinction is a part of life, and animals and plants disappear all the time. About 98% of all the organisms that have ever existed on our planet are now extinct. When a ...

Humans have wiped out hundreds of species — with many more on the brink or experiencing large declines in population. Some scientists have argued that we have entered a “sixth mass extinction” event ...