Marine counterparts of land creatures

The idea that there are specific marine counterparts to land creatures, inherited from the writers on natural history in Antiquity, was firmly believed in Islam and in Medieval Europe, and is exemplified by the creatures represented in the medieval animal encyclopedias called bestiaries and in the parallels drawn in the moralising attributes attached to each. "The creation was a mathematical diagram drawn in parallel lines," T.H. White said a propos the bestiary he translated. "Things did not only have a moral they often had physical counterparts in other strata. There was a horse in the land and a sea-horse in the sea. For that matter there was probably a Pegasus in heaven". The idea of perfect analogies in the fauna of land and sea was considered part of the perfect symmetry of the Creator's plan, offered as the "book of nature" to mankind, for which a text could be found in Job:

"But ask the animals, and they will teach you, or the birds of the air, and they will tell you; or speak to the earth, and it will teach you, or let the fish of the sea inform you. Which of all these does not know that the hand of the Lord has done this? In his hand is the life of every creature and the breath of all mankind."

All of Creation was considered to reflect the Creator, and Man could learn about the Creator through studying the Creation, an assumption that underlies the "Watchmaker analogy" offered as a proof of God's existence.

The correspondence between the realms of earth and sea, extending to its denizens, offers examples of the taste for allegory engendered by Christian and Islamic methods of exegesis, which also encouraged the doctrine of signatures, a "key" to the meaning and use of herbs.

The source text that was most influential in compiling the bestiaries of the 12th and 13th centuries was the Physiologus, one of the most widely read and copied secular texts of the Middle Ages. Written in Greek in Alexandria the 2nd century CE and accumulating further "exemplary" beasts in the next three centuries and more, Physiologus was transmitted in the West in Latin, and eventually translated into many vernacular languages: many manuscripts in various languages survive.Aelian, On the Characteristics of Animals (A.F. Scholfield, in Loeb Classical Library, 1958).

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