Farther back in our planet’s history, volcanic eruptions, rapid climate change, and plummeting oxygen levels have caused at least four additional mass extinctions, with smaller pulses of biodiversity ...

Scientists have long treated mass extinctions as events locked deep in the fossil record. That framing now feels less distant ...

Human activity has accelerated extinction rates, raising concerns that we may be entering a sixth mass extinction.

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 ...