A scientist holds up the brains of two types of birds. The huge brain belonged to a crow, and the small one to a duck. Which helps to explain why urban corvids are so bloody clever, why they can use the wheels of cars to crack open nuts. Tokyo has 20,000 of these birds—small compared to the city's human population (13 million). The documentary is a poem—meaning it has no narrative structure or some crow specialist who consistently feeds us facts about the habits of this species. It captures only random moments, brief ideas, snatches of scientific information about the accidental relationship between them and us. (CHARLES MUDEDE)