As we have discussed, bestiaries seem to utterly fail at any sort of easy organization. The work modern readers call a “bestiary” covers everything from beasts to stones. The bestiary T.H. White translated and the Aberdeen bestiary both follow the same progression. They begin with beasts, either prologues or disrupted by a discussion of Creation, then proceed to Birds, Snakes, Worms, Fish, Trees, Man, and finally ending at Stones. Even within each section, there is great difficulty in analyzing why each thing is classified within the group. Beings which are viewed today as fantastic stand along the most mundane and individual sections range from something as large as an elephant to as small as an ant (literally). The relationship the text places the animals across classifications is even more confusing. So, I will here re-iterate what the class presented, the issues with what was discussed, and finally present theory as to why the bestiary is organized the way it is.
The discussion of the bestiary must begin with analysis of what sections are present, and what medieval authors placed in those sections. So, we begin with beasts. At first glance, it seems that this merely refers to terrestrial animals. However, snakes and lizards are contained within their own section, and the amphibians are split. So, perhaps the definition of “large upright terrestrial animal” works better? Again, it seems close, but the theory is broken on two fronts. The first occurs at the end of the Aberdeen Bestiary’s section of beasts: the ant. If something as small as an ant counts as a beast, then “large” cannot be part of the definition. The other argument against this lies in the section on “Man” who is clearly terrestrial, clearly similar to some beasts (i.e. monkeys), and is certainly large. The primary physical difference to medieval authors, though, is that Man walks upright and clothes himself; the beasts do not. So, it appears that a close definition to categorize what is a beast is “All things which walk above their belly on at least four legs”. This eliminates lizards, which have splayed legs, and fish, which do not walk. The precise means of locomotion is the core argument within the definition, and is one which the class eventually decided on as a scale for categorizing a new animal into a section.
Let us see what the definition of every other section is. Birds are those things which fly. This includes some beings which appear anomalous to modern scientists (i.e. Bats and Bees). Notably, medieval thinkers were perfectly aware that bats were mammals, and comment that they are unusual among the birds in that way (Aberdeen Bestiary Folio 51v). However, this simply did not matter to them, as it fit the definition of what a bird was. Snakes are those things which slither or crawl. Scales are not required, as the salamander does not have them. Notably, the medieval concept of a dragon does fit this definition, as the Aberdeen Bestiary states that the dragon’s “strength lies not in its teeth but its tail” (Folio 66r). This description to a modern observer seems to fit more closely with a boa or other snake, and the depiction on the previous page, in which the dragon only has two very small legs and no wings, seems to support this. Worms are a little more complicated. To the medieval writers, the section on worms seems to serve as a catch-all for all bugs which do not fit any other definition. For that, we have leeches, millipedes, ticks, fleas, and spiders all in the same class. The bestiary White translated mentions that the worms generate from the elements, so that a spider is generated from air, the leech from water, etc. In this case, locomotion does not serve as the best definition.
Fish are simply those things which live primarily in the water, if we follow White’s bestiary. This creates an issue, as nearly stationary things, such as clams, are fish alongside whales and crocodiles. The Aberdeen bestiary, however, is more restrictive, eliminating shellfish from the roster of fish. In that case, merely primarily swimming is a perfectly viable definition for a fish. Trees are those things which only move vertically as they grow, so their lack of locomotion the other categories have is in fact the definition of the section on trees.
To this point, the relationship between the sections has been clear. Beasts are the closest below man on the rank of how close to the divine image they are, then birds which fly close to heaven, then the other being of the land, then the fish of the sea, then those things which cannot move to seek perfection. The final two sections destroy that organization. Man is defined by his intellect, not his locomotion. It is this attribute, which medieval writers defended endlessly, that separates man from everything following. Stones refer only to precious and semiprecious stones; not merely any rock will do. Interestingly, for the Aberdeen bestiary, this includes pearl-oysters as something distinct from pearls. Specifically, these stones are those which are used to build the heavenly Jerusalem as seen by St. John in Revelation, and bear special relationship to God. However, these are some of the first things created; any argument that a bestiary is organized in terms of decreasing perfection would not place stones next to Man. So, some deeper organization is required.
What I propose is that the bestiary is organized according to two separate hierarchies. The first is the list of living things in terms of decreasing perfection. Beasts, as the most active and similar to humans, are the top, and trees, which can merely grow upwards towards heaven, without fulfilling any tasks on Earth are the lowest. This governs the first seven books of the bestiary perfectly. However, a new rule takes control for the final two books. To this point, the bestiary serves as an encyclopedia of things which the readers may or may not have viewed before. Even the common beasts, such as sheep or cats, are still somehow different, and can be described formally in relation to other beasts well. The more exotic beasts are even better, as it is a chance to bring classical knowledge of beasts never before seen to medieval audiences. However, Man is an uninteresting topic, even if it is the only one governed by intellect. Every person has a conception of what a Man is, just as every person has seen topaz or other jewels inside the altars of the great cathedrals. That was no different in the Middle Ages than it is now. So, in a full encyclopedia of Creation, these have to be treated carefully to not cause insult or boredom. So, I believe that the final two books are arranged in the two most divine things. First comes Man, greater than all created before in life, and given governance over all the beings described previously. Stones, however, are the very foundation of Heaven, used by God to construct the walls of the city of the faithful. A description of precious gems is then also a description of the most direct work of the Father. In addition, ending with stones serves as a mirror then of Revelation. The work seeks to clarify all things made in the Creation, and give glory to God through knowledge of his world, and it is only fitting to end with the people to inherit that creation and a final vision of what it is they shall inherit.