This chapter examines the role of animals in divination in ancient times. It discusses ancient observers' interpretaion of signs coming from instinctive animal behaviour and from the structure of animal body parts. It explains the three main currents of philosophical thought on divination. Plato and Aristotle believed the divinatory insights to be tied with animal instinct and belong to a fringe form of cognition that is specifically connected with humans' animal natures. On the other hand, the Stoics considered divination as an important piece of their understanding of the cosmos as a whole, and of humans as part of it.