Animals of the Past

by Frederic A. Lucas

THE ANCESTRY OF THE HORSE

"Said the little Eohippus
I am going to be a horse
And on my middle finger-nails
To run my earthly course."

The American whose ancestors came over in the "Mayflower" has a proper pride in the length of the line of his descent. The Englishman whose genealogical tree sprang up at the time of William the Conqueror has, in its eight centuries of growth, still larger occasion for pluming himself on the antiquity of his family. But the pedigree of even the latter is a thing of yesterday when compared with that of the horse, whose family records, according to Professor Osborn, reach backward for something like 2,000,000 years. And if, as we have been told, "it is a good thing to have ancestors, but sometimes a little hard on the ancestor," in this instance at least the founders of the family have every reason to regard their descendants with undisguised pride. For the horse family started in life in a small way, and the first of the line, the Hyracotherium, was "a little animal no bigger than a fox, and on five[14] toes he scampered over Tertiary rocks," in the age called Eocene, because it was the morning of life for the great group of mammals whose culminating point was man. At that time, western North America was a country of many lakes, for the most part comparatively shallow, around the reedy margins of which moved a host of animals, quite unlike those of to-day, and yet foreshadowing them, the forerunners of the rhinoceros, tapir, and the horse.

[14] Four, to be exact; but we prefer to sacrifice the foot of the Hyracothere rather than to take liberties with one of the feet of Mrs. Stetson's poem.

The early horse—we may call him so by courtesy, although he was then very far from being a true horse—was an insignificant little creature, apparently far less likely to succeed in life's race than his bulky competitors, and yet, by making the most of their opportunities, his descendants have survived, while most of theirs have dropped by the wayside; and finally, by the aid of man, the horse has become spread over the length and breadth of the habitable globe.

Fig. 33.—Skeleton of the Modern Horse and of His Eocene Ancestor.

Now right here it may be asked, How do we know that the little Hyracothere was the progenitor of the horse, and how can it be shown that there is any bond of kinship between him and, for example, the great French Percheron? There is only one way in which we can obtain this knowledge, and but one method by which the relationship can be shown, and that is by collecting the fossil remains of animals long extinct and comparing them with the bones of the recent horse, a branch of science known as Palæontology. It has taken a very long time to gather the necessary evidence, and it has taken a vast amount of hard work in our western Territories, for "the country that is as hot as Hades, watered by stagnant alkali pools, is almost invariably the richest in fossils." Likewise it has called for the expenditure of much time and more patience to put together some of this petrified evidence, fragmentary in every sense of the word, and get it into such shape that it could be handled by the anatomist. Still, the work has been done, and, link by link, the chain has been constructed that unites the horse of to-day with the horse of very many yesterdays.

The very first links in this chain are the remains of the bronze age and those found among the ruins of the ancient Swiss lake dwellings; but earlier still than these are the bones of horses found abundantly in northern Europe, Asia, and America. The individual bones and teeth of some of these horses are scarcely distinguishable from those of to-day, a fact noted in the name, Equus fraternus, applied to one species; and when teeth alone are found, it is at times practically impossible to say whether they belong to a fossil horse or to a modern animal. But when enough scattered bones are gathered to make a fairly complete skeleton, it becomes evident that the fossil horse had a proportionately larger head and smaller feet than his existing relative, and that he was a little more like an ass or zebra, for the latter, spite of his gay coat, is a near relative of the lowly ass. Moreover, primitive man made sketches of the primitive horse, just as he did of the mammoth, and these indicate that the horse of those days was something like an overgrown Shetland pony, low and heavily built, large-headed and rough-coated. For the old cave-dwellers of Europe were intimately acquainted with the prehistoric horses, using them for food, as they did almost every animal that fell beneath their flint arrows and stone axes. And if one may judge from the abundance of bones, the horses must have roamed about in bands, just as the horses escaped from civilization roam, or have roamed, over the pampas of South America and the prairies of the West.

The horse was just as abundant in North America in Pleistocene time as in Europe; but there is no evidence to show that it was contemporary with early man in North America, and, even were this the case, it is generally believed that long before the discovery of America the horse had disappeared. And yet, so plentiful and so fresh are his remains, and so much like those of the mustang, that the late Professor Cope was wont to say that it almost seemed as if the horse might have lingered in Texas until the coming of the white man. And Sir William Flower wrote: "There is a possibility of the animal having still existed, in a wild state, in some parts of the continent remote from that which was first visited by the Spaniards, where they were certainly unknown. It has been suggested that the horses which were found by Cabot in La Plata in 1530 cannot have been introduced."