Birds show bewildering diversity in their life histories, mating systems and risk of extinction. Why do albatrosses delay reproduction for the first 12 years of their life while zebra finches breed in their first year? Why are fairy-wrens so sexually promiscuous while swans show lifelong monogamy? Why are over a quarter of parrot species threatened with global extinction while woodpeckers and cuckoos remain secure? Some of these topics are classic...