Chapter XIV.
Birds are connected to fish with various relationships; however, they do not lack the function of feet. About the various types and differences of different birds.
45. However, after the description of the fish, a discussion followed about those birds which are accustomed to the waters, because they also delight in swimming and have a talent for it. Therefore, the first connection seems to be between these birds and fish, because there seem to be certain commonalities in swimming between both groups. The second connection is also shared by all birds and fish, because the use of flying is similar to swimming. For just as a fish cuts through water by swimming, so a bird cuts through the air with rapid flight. And both species similarly have tails and wings for propulsion; just as fish raise themselves with the wings to the front, and proceed to the back, they also easily turn their tails with a rudder wherever they want, or direct themselves with a certain force from the opposite direction. Birds also float in the air like they do in water, and as if they extend their wings, they also raise their tails to the higher parts or submerge them in the lower parts. Since in some respects the same use and appearance exist, therefore the creation of both kinds of waters has proceeded from the divine precept. For God said: Let the waters bring forth reptiles having life according to their kind, and flying creatures above the earth under the firmament of heaven according to their kind. Therefore, not without reason, because both kinds are produced from water, swimming is suitable for both.
Certainly, both the smooth snake and all other serpents (for the name 'serpent' is given to them because they cannot walk but instead creep), as well as dragons, are in a similar manner to fishes mostly without feet; no kind of birds is without the function of feet, because they all live on land; and therefore they are supported by the function of feet, because they need this kind of service for seeking food. And so, some birds are armed with talons for seizing prey, like hawks and eagles which practice hunting for plunder: others, either for walking or for preparing food for themselves, use a fitting use and service.
47. However, there is one name for birds, but different kinds; how could anyone comprehend them with memory or knowledge? Therefore, there are birds that feed on flesh. That is why they have rough claws, a curved and sharp beak, and swift flight; because they live by snatching, so they can quickly seize the prey they follow, and quickly disembowel it with their mouth or claws. There are also birds that feed on discovered seeds: others on different and accidental food. There is also a variety of mating, for the sake of which they engage in raids. For due to their greed for plundering, or for the sake of spying, they do not agree with each other; and therefore they avoid joining together. For avarice rejects the partnership of many. Furthermore, the joining together of many would easily expose itself. Therefore, there is no mating partnership for these birds except the yoke of partnership. Therefore, eagles and hawks have this way of life. On the other hand, pigeons, cranes, starlings, crows, and magpies, as well as thrushes, enjoy the union of many.
48. There are also other types of birds, some of which stay in one place at all times, others that travel to different regions and return after winter is over. There are also some that return during winter and migrate during summer; either because they move to warmer places during winter, or because they prefer to spend most of their time in the more pleasant locations they know. Finally, thrushes return at the end of autumn, near the beginning of winter, as if summer had come to an end. They endeavor to ensnare us with inhospitable cruelty, trying to deceive us now with treacherous traps, now with sticky snares, now with lures. The return of the storks raises the banner of spring. Cranes, because they seek the heights, often love to wander.
49. Some birds subject themselves to the hand, and become accustomed to the master's table, and are soothed by touch: others are afraid: others delight in the same dwellings as humans: others love a hidden life in the deserts, which they compensate for by their love of freedom and the difficulty of seeking food. Some birds only make noise with their voices: others delight with their melodious and sweet modulation. Some speak naturally, others speak with the training of different voices, so that you might think a bird is speaking when it is actually a human speaking. How sweet is the song of the blackbird, how distinct is the voice of the parrot! There are also other simple birds, like doves: others cunning, like partridges: the rooster is more boastful, the peacock more splendid. There are also different ways of life among birds; some work together for the common good and, using their combined strength, take care of the state as if under a king; others focus on themselves, refuse authority, and if captured, prefer to leave servitude unworthy of them.