Why would a grown man chase hornets with a thermometer, paint whirligig beetles bright red, or track elephants through the night to fill trash bags with their prodigious droppings? Some might say--to advance science. Bernd Heinrich says--because it's fun. Heinrich, author of the much acclaimed Bumblebee Economics, has been playing in the wilds of one continent or another all his life. In the process, he has become one of the world's...