MIT geophysicist predicts a sixth mass extinction by 2100
MIT geophysicist Daniel Rothman, who studied Earth's five mass extinction events over the last 540 million years, found human activities could add enough carbon to world's oceans by 2100, triggering another mass extinction. Rothman identified "thresholds of catastrophe" from previous carbon cycles, crossing which could lead to a sixth mass extinction event, lasting for about 10,000 years.