A renowned biologist explores the evolutionary and environmental reasons behind why birds do what they do. Biologist Bridget Stutchbury takes readers along on her escapades as a bird detective, stalking subjects through the woods for hours, taking blood samples from nestlings for DNA analysis, and mounting miniature tracking devices on tiny backs. She captures several young white-and-brown male purple martins and paints them the darker color of mature males to see if the painted youngsters are more successful than their unaltered peers in wresting away nest sites from older males. They are nbsp;The Private Lives of Birds is a treasure trove of fascinating insights into bird behavior. But understanding the social lives of birds does much more than slake our curiosity. Aware that many birds will not occupy an area unless other birds are already there, biologists used mirrors and two-dimensional cutouts to lure Atlantic puffins to establish colonies off the coast of Maine, getting curious puffins to visit the site and linger long enough to encounter a live bird. As Stutchbury says, “Trying to save birds without understanding what makes them tick is a shot in the dark ... birds are highly social, and their social needs are at least as important as their physical needs.”