Paleobiologists have discovered that extinctions of large numbers of species have occurred at intervals of around 26 million years. The last such mass extinction episode took place some 11.3 million years ago, so the next large-scale renewal of species should be due about 10 million years from now.
古生物學者發現，物種的大量滅絕約二千六百萬年會上演一次，上一回物種的滅絕顛峰距今一千一百三十萬年，因此下一次的物種大換血應在一千萬年以後。