"We should never forget that it is these personal struggles that make up the extinction process ... Extinction is not a cold calculus about the numbers of breeding females and the degree of genetic ...

There have been five unquestionably great extinctions on earth: the end-Ordovician, the late-Devonian, the end-Permian, end-Triassic, and the end-Cretaceous extinctions. Some think we are now in a ...