The Hollow Bones implores us to pay careful attention to the crucial lessons we might learn from our not-too-distant history. I remember you once told me about mockingbirds and their special talents for mimicry. They steal the songs from others, you said. I want to ask you this: how were our own songs stolen from us, the notes dispersed, while our faces were turned away? Berlin, 1936. Ernst Schäfer, a young, ambitious zoologist and keen hunter and...