Bestiary

A bestiary, or bestiarum vocabulum, is a compendium of beasts. Originating in the Ancient world, bestiaries were made popular in the Middle Ages in illustrated volumes that described various animals, birds and even rocks. The natural history and illustration of each beast was usually accompanied by a moral lesson. This reflected the belief that the world itself was the Word of God, and that every living thing had its own special meaning. For example, the pelican, which was believed to tear open its breast to bring its young to life with its own blood, was a living representation of Jesus. The bestiary, then, is also a reference to the symbolic language of animals in Western Christian art and literature.

The earliest bestiary in the form in which it was later popularized was an anonymous 2nd century Greek volume called the Physiologus, which itself summarized ancient knowledge and wisdom about animals in the writings of classical authors such as Aristotle's Historia Animalium and various works by Herodotus, Pliny the Elder, Solinus, Aelian and other naturalists.

Following the Physiologus, Saint Isidore of Seville (Book XII of the Etymologiae) and Saint Ambrose expanded the religious message with reference to passages from the Bible and the Septuagint. They and other authors freely expanded or modified pre-existing models, constantly refining the moral content without interest or access to much more detail regarding the factual content. Nevertheless, the often fanciful accounts of these beasts were widely read and generally believed to be true. A few observations found in bestiaries, such as the migration of birds, were discounted by the natural philosophers of later centuries, only to be rediscovered in the modern scientific era.

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