article_snippet.sent: Writer Stewart Brand said: 'The five historic mass extinctions eliminated 70 per cent or more of all species in a relatively short time.
article_snippet.sent: Around 26 per cent of all marine families were wiped out and 60 per cent of all genera - an estimated 82-88 per cent of all species.
article_snippet.sent: Three quarters of all species on Earth died out in the Late Devonian mass extinction, though Three quarters of all species on Earth may have been a series of extinctions over several million years.
article_snippet.sent: Around 22 per cent of all marine families, and 57 per cent of all genera were wiped out - an estimated 79-87 per cent of all species.
article_snippet.sent: All life on Earth today is descended from the 4 per cent of species that survived.
article_snippet.sent: There were two or three phases of extinction that made up the Triassic-Jurassic mass extinction event. 
article_snippet.sent: 22 per cent of all marine families and 53 per cent of all genera -
article_snippet.sent: an estimated 76-84 per cent of all species.
article_snippet.sent: However, many other organisms perished including 16 per cent of all marine families and 47 per cent of all genera -
article_snippet.sent: an estimated 71-81 per cent of all species.