The End of the Dinosaurs: Chicxulub Crater and Mass Extinctions

Approximately 65 million years ago, at the close of the Cretaceous era, Earth underwent a major bout of extinctions. Seventy percent of all species, including all of the dinosaurs, died out in a relatively short time. In this attractive volume, Frankel (Volcanoes of the Solar System) attempts to pinpoint the cause of this devastation. Summarizing a wealth of scientific information, he argues that either a comet or a huge asteroid slammed into Earth near Puerto Chicxulub, Mexico, releasing a massive amount of energy. The smoke from the enormous fires that ensued, coupled with the colossal amount of debris flung into the atmosphere by the impact, blocked sunlight, changed climate worldwide and led to the extinctions. A true science detective, Frankel marshals his facts, outlines the search for culprits, describes the scene of the crime and portrays the other sleuths on the case. He gives short shrift to alternative explanations (such as volcanic activity) for the mass extinction, however. His well-informed book, initially published in France in an earlier version, concludes with one chapter providing inconclusive evidence linking many of Earth's other major extinction events to impacts, and another chapter discussing steps that can be taken to avert future collisions. 67 halftones, nine line diagrams. (Sept.)