The Animal Sciences is like a science fair project. Take a group of friends – the missing Robin, crazy Kookla, jealous Duffer, lost Autumn and Latvian Igor – add baking soda and vinegar, and watch what happens. As the story rockets back and forth between the past and present, the consecutive anecdotes start to coalesce into something more than the sum of its parts, and we begin to see how the different atoms – the characters – of this particular molecule are interdependent. We come to suspect, too, that just as the laws of nature make that baking-soda volcano inevitable, so too do they rule human relationships, making volcanoes out of some chemical reactions and warmth out of others. Maybe, just maybe, human sciences aren't so different from the animal ones.

What is it that makes us human? Could it be love?