Aristotle's History of Animals / In Ten Books

by Aristotle

8. There is a great difference in the teeth of animals, both among themselves and from the human type; all viviparous and sanguineous quadrupeds have teeth; some have teeth in both jaws, which others have not; this is the first distinction. Those which have horns do not possess teeth in both jaws, for they have no front teeth in the upper jaw. There are others, as the camel, which, though it has no horns, has not teeth in the upper jaw.

9. Some animals have tusks like the boar, others have not; some have pointed teeth, as the lion, panther, and dog; the teeth of others have an even surface, as the ox and the horse. Animals with pointed teeth have their teeth fitting into each other; no animal has both tusks and horns, neither those with pointed teeth nor any others. Most animals have their front teeth sharp, and their hind teeth flat; all the teeth of the seal are sharp pointed, showing an approximation to the race of fishes, for all fishes have pointed teeth.

10. None of these genera have a double row of teeth. But, if we may believe Ctesias, there are some which have this peculiarity, for he mentions an Indian animal called martichora, which had three rows of teeth in each jaw; it is as large and as rough as a lion, and has similar feet, but its ears and face are like those of a man; its eye is grey, and its body red; it has a tail like a land scorpion, in which there is a sting; it darts forth the spines with which it is covered instead of hair, and it utters a noise resembling the united sound of a pipe and a trumpet; it is not less swift of foot than a stag, and is wild, and devours men.

11. Man sheds his teeth, and so do other animals, as the horse, the mule, and the ass; man sheds his front teeth, but no animal sheds the molar teeth; swine do not shed any of their teeth. About dogs, there is some doubt; some persons think they do not shed their teeth at all, others that they shed only the canine teeth; but it has been observed that they do shed their teeth like men: perhaps it has escaped notice, because they do not shed them before the inner ones, which are similar, are grown up.

12. And it is probable that the same takes place in other wild animals, since they are said only to shed their canine teeth. Young dogs are known from old ones by their teeth, for young dogs have sharp white teeth, old dogs have them black and blunted. The horse is in this respect different from all other animals; for while the teeth in other animals become darker as they grow older, in the horse they become more white.

13. Those which are called canine teeth are placed between the cutting and the molar teeth, and partake of the nature of both, for they are wide below, but sharp at the top. The male has more teeth than the female in mankind, and sheep, and goats, and swine. This has not been observed in other animals. Those persons which have the greatest number of teeth are the longest lived; those which have them widely separated, smaller, and more scattered, are generally more short lived.

14. The last molar teeth, which are called wisdom teeth, appear, both in the male and female about the age of twenty, and some women cut the molar teeth at eighty years of age, causing great pain in the extremity of the jaw, and some men also: this happens with persons who do not cut their wise teeth at the proper age.

15. The elephant has four teeth on each side, with which he grinds his food, for he reduces his food very small, like meal. Besides these, he has two tusks: in the male these are large, and turned upwards; in the female they are small, and bent in the contrary direction. The elephant has teeth as soon as it is born; but the tusks are small, and therefore inconspicuous at first. It has so small a tongue within its mouth, that it is difficult to see it.

Chapter IV.

1. Animals have very differently-sized mouths, for some have wide, open mouths, as the dog, the lion, and all animals with pointed teeth; other animals have a small mouth, as man, or a moderately-sized one, as the swine. The Egyptian river-horse has a mane like a horse, and a cloven hoof like the ox; it has a flat face; the talus is like that of other animals with cloven hoofs, and it has large projecting teeth; it has a tail like a hog, and utters a sound like the neighing of a horse; it is about the size of an ass, and its skin is so thick that shields are made of it; its intestines are like those of a horse or ass.