cover image The Beak of the Finch: A Story of Evolution in Our Time

The Beak of the Finch: A Story of Evolution in Our Time

Jonathan Weiner. Alfred A. Knopf, $30 (332pp) ISBN 978-0-679-40003-5

For more than 20 years Rosemary and Peter Grant have divided their time between Daphne Major in the Galapagos and Princeton University. On the tiny island they have intensively studied six species of Darwin's ground finches; at Princeton, they analyze their collected data. In following their work Weiner ( Planet Earth ) tells a remarkable story of continuing evolution, and of the painstaking research that reveals it. The Grants documented two dramatic changes in the finches: after a drought in 1977 reduced their numbers by 85%, the surviving birds became larger, in weight, wingspan and beak; after El Nino's floods in 1983, the trend was reversed. The Grants found that during food shortages the difference of one millimeter in the size of a finch's beak could determine its life or death. In his eloquent and richly informative report, Weiner surveys as well research on evolution being done on crossbills, sticklebacks and fruit flies. Illustrations. 40,000 first printing; BOMC, QPB , History Book Club and Natural Science Book Club alternates. (May)