Rosemary and Peter Grant and those assisting them have spendtwenty years on Daphne Major, an island in the Galapagos studyingnatural selection. They recognize each individual bird on theisland, when there are four hundred at the time of the author'svisit, or when there are over a thousand. They have observed abouttwenty generations of finches -- continuously. Jonathan Weiner follows these scientists as they watch Darwin'sfinches and come up with a new understanding of life itself.
