The Great Dying

Scientists link volcanic warming to Great Dying

The greatest catastrophe in Earth's history, a massive worldwide extinction of species that engulfed the planet 250 million years ago, may not, as many scientists suspect, have occurred with a bang but with a prolonged and deadly global gasp.

Scientists from four continents reported yesterday that the event known as the Great Dying, which wiped out more than three-quarters of all species on Earth, may have been the result of volcano-induced global warming -- not the impact of a comet or asteroid, as some scientists suspect.

"Animals and plants both on land and in the sea were dying at the same time and apparently from the same causes: too much heat and too little oxygen," says University of Washington paleontologist Peter Ward, who headed one of two studies on the event published in the journal Science.