What Is a Bestiary? Animal Books That Were Never About Animals

A typical entry follows a consistent structure. It names the animal, frequently offers an etymology explaining the name as revealing the creature's nature, describes its appearance and behaviour drawing on earlier written sources rather than observation, and then supplies a moral or theological interpretation, explaining what the animal signifies about God, Christ, the devil, the soul or the conduct expected of a Christian. The pelican wounding its own breast to revive its young signifies the crucifixion. The lion cub born dead and revived on the third day signifies the resurrection. The phoenix signifies the same. The fox feigning death to catch birds signifies the devil's deceptions. Once that structure is recognised, the apparent credulity of the texts looks different, since the compiler was assembling a system of symbols with scriptural and moral content, and an animal that did not exist served that purpose as well as one that did.

The tradition is textual and its sources can be traced with unusual precision:

• •The Physiologus, a Greek compilation probably from Alexandria in the second or third century, which supplied the basic structure and much of the content and was translated into many languages
• •Classical natural history, principally Pliny the Elder, whose work transmitted both genuine observation and a great deal of hearsay
• •Isidore of Seville's seventh-century encyclopaedia, which supplied etymologies used as interpretative keys
• •Scriptural references to animals, which required explanation and which the bestiaries supplied
• •Later additions and reorganisations, producing recognisable families of manuscripts that scholars use to trace transmission
• •Illustration traditions, which frequently copied earlier images rather than living animals, which is why some creatures drift steadily further from their appearance across successive copies

Copying from texts rather than from life produces characteristic patterns. An error introduced once is reproduced indefinitely, and mistranslation generates creatures, with several fabulous animals traceable to a misread word. Descriptions of exotic animals compound, since a compiler in northern Europe describing an elephant worked from a text by someone who may also never have seen one. Illustrations degrade the same way, which is why the whale is drawn as an island with trees on it, and why some medieval lions look nothing like lions while medieval dogs and hares look entirely convincing, the difference being whether the illustrator had access to the animal. The tradition also had no mechanism for correction, since authority came from earlier written sources rather than from observation, so a report in a respected text outweighed anything anyone could see, which is precisely the habit that later natural history had to break in order to become a science.

A handful of entries account for most of the tradition's afterlife and each carries a fixed meaning:

• •The unicorn, untameable except by a virgin in whose lap it lays its head, read as an image of the incarnation, and probably derived ultimately from garbled accounts of the rhinoceros
• •The pelican, piercing its breast to feed or revive its young with its own blood, which became a standard image of sacrifice and appears widely in church decoration and heraldry
• •The phoenix, consumed by fire and rising from its own ashes, read as resurrection and borrowed from classical and older eastern sources
• •The whale, mistaken by sailors for an island until they light a fire on its back, read as the devil deceiving those who trust him
• •The beaver, said to bite off the organs hunters pursue it for and escape, read as renouncing sin, and resting on a mistaken belief about what the animal was hunted for
• •The salamander, believed to live in fire unharmed, which attached itself to the word for a creature that merely emerges from damp logs thrown on a hearth

Bestiaries shaped European visual culture far beyond the manuscripts. Heraldry draws directly on their symbolic vocabulary, so the animals on coats of arms mean what the bestiaries said they meant. Church carving, misericords, capitals, roof bosses and stained glass reproduce their creatures, and a great deal of medieval architectural sculpture is unintelligible without them. Literary allusion depends on them, since a medieval or early modern reference to a pelican, a phoenix or a unicorn carries an established meaning rather than a description. The tradition faded as observation-based natural history developed from the sixteenth century onward, though early printed natural histories retain substantial bestiary content alongside genuine zoology, which makes the transition visible within single volumes. The form has been revived repeatedly as a literary device, with modern writers and artists producing bestiaries that use the structure knowingly, since a catalogue of creatures each carrying a meaning remains a useful way to organise a book.

Each entry names an animal, describes it from earlier texts and then explains what it signifies, and the significance was the purpose, so a creature that did not exist served as well as one that did. The material descends from a Greek compilation of the second or third century through Pliny and Isidore. Authority came from written sources rather than observation, so errors were copied indefinitely. Heraldry and church carving still speak this vocabulary.