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New Way to Read the Record Suggests Abrupt Extinction

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Science  22 Nov 1996:
Vol. 274, Issue 5291, pp. 1303-1304
DOI: 10.1126/science.274.5291.1303


Everyone has heard that an asteroid or comet slammed into Earth 65 million years ago, but did this impact really kill off thousands of species, including the dinosaurs? For many species, the record suggests gradual, not catastrophic, extinction, so paleontologists have been skeptical. But on page 1360, researchers using statistical analyses of the fossil record suggest that at least one type of sea creature, the ammonites, was indeed snuffed out quickly at the time of the impact.