terremoto in Giappone: la mappa delle scosse

Attendete il caricamento

View full map

la sesta estinzione di massa?

Credit: Nicolle Rager Fuller, National Science Foundation

Negli ultimi 540 milioni d'anni ci sono state cinque grandi estinzioni di massa. In ognuna di esse sono scomparse il 75% delle specie presenti.

"If you look only at the critically endangered mammals--those where the risk of extinction is at least 50 percent within three of their generations--and assume that their time will run out and they will be extinct in 1,000 years, that puts us clearly outside any range of normal and tells us that we are moving into the mass extinction realm," said Anthony Barnosky, an integrative biologist at the University of California at Berkeley, and first author of the paper.
...
"A modern global mass extinction is a largely unaddressed hazard of climate change and human activities," said H. Richard Lane, program director in the National Science Foundation's (NSF) Division of Earth Sciences, which funded the research.

continua su Earth's Sixth Mass Extinction: Is It Almost Here?