It has been nearly exterminated a couple of times, or at least the population driven low.

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Humans spread out, exterminated the easy prey and probably the competing hominids and populated the livable earth.

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Of course, that might just mean that the Clovis people had not quite exterminated bison before they, themselves, disappeared.

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And once they are exterminated, the ecology of their native reef can change in ways that make their return impossible.

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Having missed their opportunity 9m years earlier, man's ancestors and their kin now grabbed it, moving into the niches vacated by their recently exterminated cousins.

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The fifth, the end-Cretaceous event, which occurred sixty-five million years ago, exterminated not just the dinosaurs but seventy-five per cent of all species on earth.

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The spill exterminated a quarter-million seabirds and thousands of marine mammals.

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The six million men, women and children exterminated by the Nazis belonged to a great people not predestined to martyrdom, but the victim of gratuitous barbarism.

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For the most part, smallpox was exterminated decades ago.

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In the AI optimist camp, futurist and Google director of engineering Ray Kurzweil also sees intelligent machines precipitating human extinction, of a sort, only in Kurzweil's telling, humanity is not exterminated but subsumed into a superintelligent machine.

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The perfection bug has to be exterminated.

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