Centennial (11 page)

These profound evolutions occurred on the plains that surrounded the site of the twin pillars. There on flat lands that knew varied climates, from tropical to sub-arctic, depending upon where the equator was located at the time, this singular breed of animal went through the manifold changes that were necessary before it stood forth as an accomplished horse.

One of the biggest changes in the antecedents of the horse appeared about six million years ago, when pliohippus, the latest in the breed, evolved with only one toe on each foot and with the pads on which his ancestors had run eliminated. It now had a single hoof. This animal was a medium-sized beautiful horse in almost every sense of the word, and would have been recognized as such, even from a considerable distance. There would be minor refinements, mostly in the teeth and in the shape of the skull, but the horse of historic times was now foreshadowed.

He arrived as equus about two million years ago, as splendid an animal as the ages were to produce. Starting from the mysterious and unseen ‘paleohippus,’ this breed had unconsciously and with great persistence adapted itself to all the changes that the earth presented, adhering always to those mutations which showed the” best chance of future development. ‘Paleohippus,’ of the many capacities, eohippus of the subtle form, merychippus with the horse-like appearance, pliohippus with the single hoof—these attributes persisted; there were dozens of other variations equally interesting which died out because they did not contribute to the final form. There were would-be horses of every description, some with the most ingenious novelties, but they did not survive, for they failed to adjust to the earth as it was developing; they vanished because they were not needed. But the horse, with its notable collection of virtues and adjustments, did survive.

About one million years ago, when the twin pillars were well formed, a male horse with chestnut coloring and flowing tail lived in the area as part of a herd of about ninety. He was three years old and gifted with especially strong legs that enabled him to run more swiftly than most of his fellows. He was a gamin creature and had left his mother sooner than any of the other males of his generation. He was the first to explore new arrivals on the prairie and had developed the bad habit of leading any horses that would follow on excursions into canyons or along extended draws.

One bright summer morning this chestnut was leading a group of six adventurous companions on a short foray from the main herd. He took them across the plains that reached out from the twin pillars and northward into a series of foothills that contained passageways down which they galloped in file, their tails flowing free behind them as they ran. It was an exhilarating chase, and at the end of the main defile they turned eastward toward a plain that opened out invitingly, but as they galloped they saw blocking their way two mammoths of extraordinary size. The great smooth-skinned creatures towered over the horses, for they were gigantic, fourteen feet tall at the shoulders, with monstrous white tusks that curved downward from the head. The tips of the tusks reached sixteen feet, and if they caught an adversary, they could toss him far into the air. The two mammoths were imposing creatures, and had they been ill-disposed toward the horses, could have created havoc, but they were placid by nature, intending no harm.

The chestnut halted his troop, led them at a sober pace around the mammoths, coming very close to the great tusks, then broke into a gallop which would take him onto the eastern plains, where a small herd of camels grazed, bending awkwardly forward. The horses ignored them, for ahead stood a group of antelope as if waiting for a challenge. The seven horses passed at full speed, whereupon the fleet antelope, each with a crown of four large antlers, sprang into action, darting after them.

For a few moments the two groups of animals were locked in an exciting race, the horses a little in the lead, but with a burst of speed the antelopes leaped ahead and before long the horses saw only dust. It had been a joyous race, to no purpose other than the challenge of testing speed.

Beside the grazing area on which the antelope had been feeding there rested a family of armadillos, large rat-like creatures encased in collapsible armor. The horses were vaguely aware of them but remained unconcerned, for the armadillo was a slow, peaceful creature that caused no harm. But now the round little animals stopped searching for slugs and suddenly rolled themselves into a defensive position. Some enemy, unseen to the horses, was approaching from the south and in a moment it appeared, a pack of nine dire wolves, the scourge of the plains, with long fangs and swift legs. They loped easily over the hill that marked the horizon, peering this way and that, sniffing at the air. The wolf serving as scout detected the armadillos and signaled his mates. The predators hurried up, inspected the armor-plated round balls, nudged them with their noses and turned away. No food there.

With some apprehension, the horses watched the nine enemies cross the grassland, hoping that they would pass well to the east, but this was not to be. The lead wolf, a splendid beast with sleek gray coat, spotted the horses and broke into a powerful run, followed instantly by his eight hunting companions. The chestnut snorted and in the flash of a moment realized that he must not lead his six horses back into the canyons from which they had just emerged, for the two mammoths might block the way, allowing the dire wolves to overtake any straggler and cut him down.

So with an adroit leap sideways he broke onto the plains in the direction the antelope had taken and led his troop well away from their home terrain. They galloped with purpose, for although the dire wolves were not yet close at hand, they had anticipated the direction the horses might take and had vectored to the east to cut them off. The chestnut, seeing this maneuver, led his horses to the north, which opened a considerable space between them and the wolves.

As they ran to their own safety, they passed a herd of camels that were slower-moving. The big awkward beasts saw the apprehension of the horses and took fright, although what the cause of the danger was they did not yet know. There was a clutter on the prairie and much dust, and when it had somewhat settled, the horses were well on their way to safety but the camels were left in the direct path of the wolves. The lumbering camels ran as fast as they could, scattering to divert attack, but this merely served to identify the slowest-moving and upon this unfortunate the wolves concentrated.

Cutting at him from all sides with fearful teeth, the wolves began to wear him down. He slowed. His head drooped. He had no defense against the dire wolves and within a few moments one had leaped at his exposed throat. Another fastened onto his right flank and a third slashed at his belly. Uttering a futile cry of anguish, the camel collapsed, his ungainly feet buckling under the weight of the wolves. In a flash, all nine were upon him, so that before the horses left the area, the camel had been slain.

At a slow walk they headed south for the hills that separated them from the land of the twin pillars. On the way they passed a giant sloth who stood sniffing at the summer air, dimly aware that wolves were on the prowl. The huge beast, twice the size of the largest horse, knew from the appearance of the horses that they had encountered wolves, and retreated awkwardly to a protected area. An individual sloth, with his powerful foreclaws and hulking weight, was a match for one wolf, but if caught by a pack, he could be torn down, so battle was avoided.

Now the chestnut led his horses into the low hills, down a gully and out onto the home plains. In the distance the twin pillars—white at the bottom where they stood on the prairie, reddish toward the top, and white again where the protecting caps rested—were reassuring, a signal of home, and when all seven of the troop were through the pass, they cantered easily back to the main herd. Their absence had been noted and various older horses came up to nuzzle them. The herd had a nice sense of community, as if all were members of the same family, and each was gratified when others who had been absent returned safely.

Among the six followers accompanying the chestnut on his foray was a young dun-colored mare, and in recent weeks she had been keeping close to him and he to her. They obviously felt an association, a responsibility each to the other, and normally they would by now have bred, but they were inhibited by a peculiar awareness that soon they would be on the move. None of the older animals had signified in any way that the herd was about to depart this congenial land by the twin pillars, but in some strange way the horses knew that they were destined to move ... and to the north.

What was about to happen would constitute one of the major mysteries of the animal world. The horse, that splendid creature which had developed here at twin pillars, would desert his ancestral home and emigrate to Asia, where he would prosper, and the congenial plains at the pillars would be occupied by other animals. Then, about four hundred thousand years later, the horse would return from Asia to reclaim the pastures along the river, but by the year 6000 B.C. he would become extinct in the Western Hemisphere.

The horses were about to move north and they knew they could not accommodate a lot of colts, so the chestnut and the mare held back, but one cold morning, when they had been chasing idly over the plains as if daring the dire wolves to attack them, they found themselves alone at the mouth of a canyon where the sun shone brightly, and he mounted her and in due course she produced a handsome colt.

It was then that the herd started its slow movement to the northwest. Three times the chestnut tried unsuccessfully to halt them so that the colt could rest and have a fighting chance of keeping up. But some deep instinctive drive within the herd kept luring them away from their homeland, and soon it lay far behind them. The dun-colored mare did her best to keep the colt beside her, and he ran with ungainly legs to stay close. She was pleased to see that he grew stronger each day and that his legs functioned better as they moved onto higher ground.

But in the fifth week, as they approached a cold part of their journey, food became scarce and the wisdom of this trek, doubtful. Then the herd had to scatter to find forage, and one evening as the chestnut and the mare and their colt nosed among the scrub for signs of grass, a group of dire wolves struck at them. The mare intuitively presented herself to the wolves in an effort to protect her colt, but the fierce gray beasts were not deluded by this trick, and cut behind her and made savage lunges at it. This enraged the chestnut, who sprang at the wolves with flashing hoofs, but to no avail. Mercilessly, the wolves cut down the colt. His piteous cries sounded for a moment, then died in harrowing gurgle as his own blood drowned him.

The mare was distraught and tried to attack the wolves, but six of them detached themselves and formed a pack to destroy her. She defended herself valiantly for some moments while her mate battled with the other wolves at the body of the colt. Then one bold wolf caught her by a hamstring and brought her down. In a moment the others were upon her, tearing her to pieces.

The whole group of wolves now turned their attention to the chestnut, but he broke loose from them and started at a mad gallop back toward where the main herd of horses had been. The wolves followed him for a few miles, then gave up the chase and returned to their feast.

Mammals, unlike reptiles, had some capacity for memory, and as the trek to the northwest continued, the chestnut felt sorrow at the loss of his mate and the colt, but the recollection did not last long, and he was soon preoccupied with the problems of the journey.

It was a strange hegira on which the horses of Centennial were engaged. It would take them across thousands of miles and onto land that had been under water only a few centuries earlier. For this was the age of ice. From the north pole to Pennsylvania and Wisconsin and Wyoming vast glaciers crept, erasing whatever vegetation had developed there and carving the landscape into new designs.

At no point on earth were the changes more dramatic than at the Bering Sea, that body of ice-cold water which separates Asia from America. The great glaciers used up so much ocean water that the level of this sea dropped three hundred feet. This eliminated the Bering Sea altogether, and in its place appeared a massive land bridge more than a thousand miles wide. It was an isthmus, really, joining two continents, and now any animal that wished, or man, too, when he came along, could walk with security from Asia to America—or the other way.
(
See Map 03 – The Land Bridge
)

The bridge, it must be understood, was not constructed along that slim chain of islands which now reaches from America to Asia. Not at all. The drop of ocean was so spectacular that it was the main body of Asia that was joined substantially to America; the bridge was wider than the entire compass of Alaska.

It was toward the direction of this great bridge, barely existent when the true horse emerged, that the chestnut now headed. In time, as older horses died off, he became acknowledged leader of the herd, the one who trotted at the head on leisurely marches to new meadows, the one who marshaled the herd together when danger threatened. He grew canny in the arts of leadership, homing on the good pastures, seeking out the protected resting places.

As the horses marched to the new bridge in the northwest, to their right in unending progression lay the snouts of the glaciers, now a mile away, later on, a hundred miles distant, but always pressing southward and commandeering meadowlands where horses had previously grazed. Perhaps it was this inexorable pressure of ice from the north, eating up all good land, that had started the horses on their emigration; certainly it was a reminder that food was getting scarce throughout their known world.