About 250 million years ago, at the end of the Permian period, something killed some 90 percent of the planet's species. Less than 5 percent of the animal species in the seas survived. On land ...

Toward the end of the Permian period, Earth was reeling from cataclysmic volcanic activity in modern ... a Ph.D. candidate in Earth and planetary sciences, offered a modern analogy with land animals: ...

Toward the end of the Permian period, Earth was reeling from ... offered a modern analogy with land animals: "If someone asked you today where you'd find kangaroos, you'd say Australia," she ...