Answers such bird behavior questions as "Why do males of many species sport bright colors?' and "Why do some birds hatch naked, while others come with thick coats of down?"
I like the format of this book for people who are curious about birds: One question at a time discussed and illustrated with nice photographs.
This would be a good choice for a beginning birder or someone interested in animal behavior. For me, it mostly reinforced what I'd already learned, but there were still great tidbits for me to learn.