 By contrast, Aristotle considered the investigation of living things, and especially animals, central to the theoretical study of nature. Constituting roughly 25% of the extant corpus, his zoological writings provide a theoretical defense of the proper method for biological investigation; and they provide a record of the first systematic and comprehensive study of animals. There was nothing of similar scope and sophistication again until the 16th century. In the nineteenth century the great anatomist Richard Owen introduced a two lecture survey of Aristotle’s zoological studies by declaring that “Zoological Science sprang from his [Aristotle’s] labours, we may almost say, like Minerva from the Head of Jove, in a state of noble and splendid maturity” (Owen 1992, 91). Before examining this remarkable achievement, a few words about its creator are in  order.[1].