Ayla packed everything back up. She had no intention of depending on their dried traveling food for their morning meal, though the steppes had fewer fat birds to feed after they ate. A pair of sandgrouse fell to her sling and were roasted on a spit; some pigeon eggs that would never hatch were lightly cracked and put directly in the fire in their shells. Contributing to a filling breakfast was the fortunate find of a marmot's cache of spring beauty corms. The hole in the ground was under their sleeping furs and filled with the sweet and starchy vegetables, which had been gathered earlier by the small animal when the rootlike corms were at their peak. They were cooked with the rich pine nuts Ayla had gathered the day before, which were released from the pine cones by fire and cracked with a rock. Some fresh ripe dewberries rounded out the meal.

After they left the flooded valley, Ayla and Jondalar continued south, veering slightly toward the west, drawing imperceptibly closer to the mountain range. Though it was not an exceptionally high range, the taller peaks of the mountains were perpetually covered with snow, often shrouded with mists and clouds.

They were in the southern region of the cold continent and the character of the grassland had changed subtly. It was more than simply a profusion of grass and herbs that accounted for the diversity of animals that thrived on the cold plains. The animals themselves had evolved differences in diets and migratory patterns, spatial separations, and seasonal variations, which all contributed to the wealth of life. As in later times on the great equatorial plains far to the south – the only place that came close to matching the profound richness of the Ice Age steppes – the great abundance and variety of animals shared the productive land in complex and mutually sustaining ways.

Some specialized in eating particular plants, some in particular parts of plants; some grazed the same plants at slightly different stages of development; some fed in places that others did not go, or they followed later, or migrated differently. The diversity was maintained because eating and living habits of one species fit in between or around those of another in complementary niches.

Woolly mammoths needed great quantities of fibrous filler, rough grasses, stems, and sedges, and because they tended to bog down in deep snows, marshes or sphagnum meadows, they kept to the firm, windswept ground near the glaciers. They made long migrations along the wall of ice, moving south only in spring and summer.

Steppe horses also required bulk; like mammoths, they digested coarse stems and grasses quickly, but were somewhat more selective, preferring the mid-height varieties of grass. They could dig down through snow to find feed, but this used up more energy than they gained, and it was a struggle for them to travel when snow piled up. They could not subsist for long in deep snow and preferred the hard-surfaced, windy plains.

Unlike mammoths and horses, bison needed the leaves and sheaths of grass for the higher protein content and tended to select shortgrass, utilizing the areas of mid- and tallgrass only for new growth, usually in spring. In summer, however, an important, if inadvertent, cooperation was practiced. Horses used their teeth like clippers to bite through the tough stalks. After the horses had passed by, cutting down the stems, the densely rooted grass was stimulated to send out new leaves of regrowth. The migrations of horses were often followed, after an interval of a few days, by the gigantic bison, who welcomed the new shoots.

In winter, bison moved to southern ranges of variable weather and more snow, which kept low-growing grass leaves moist and fresher than in the dry northern plains. They were skilled at sweeping snow aside with their noses and cheeks to find their preferred close-to-the-ground feed, but the snowy steppes of the south were not without risk.

Though it kept them warm in the relatively dry cold, even of the south where more snow fell, the heavy, shaggy coats of bison and other warmly dressed animals that migrated south in winter could be hazardous or even fatal when the climate turned cold and wet, with frequent shifts between freezing and thawing. If their coats became soaking wet during a thaw, they could be vulnerable to a fatal chill during a subsequent freeze, especially if a cold snap caught them resting on the ground. Then, if their long hair froze fast, they would be unable to get up. Excessively deep snow, or icy crusts on top of snow, could also be fatal, as well as winter blizzards, or falling through the thin ice of oxbow lakes, or flooding river valleys.

Mouflon and saiga antelopes also thrived by selectively foraging on plants adapted to very dry conditions, small herbs and ground-hugging leafy shortgrass, but unlike bison, saiga did poorly on broken terrain or in deep snow, and they were not able to leap well. They were fast long-distance runners that could outdistance their predators only on the firm level surfaces of the windy steppes. Mouflon, the wild sheep, on the other hand, were expert climbers and used steep terrain to escape, but they could not dig through snow that piled up. They preferred the windblown rocky high ground.

The goatlike species related to mouflon, chamois and ibex, divided their range by altitude, or by differences of terrain and landscape, with the wild goat-antelope, ibex, taking the highest ground with the steepest crags, followed at slightly lower elevations by the smaller and very nimble chamois, with the mouflon below them. But they were all found in rough terrain of even the lowest levels of the arid steppes, since they were adapted to cold, so long as it was dry.

Musk-oxen were also goatlike animals, although larger, and their heavy double coats, which resembled the fur of mammoths and woolly rhinoceroses, made them seem bigger and more "oxlike." They nibbled continuously on the low shrubs and sedges, and they were particularly adapted to the coldest regions, preferring the extremely cold, windy, open plains close to the glacier. Though their underwool was shed in summer, musk-oxen became stressed if the weather turned too warm.

Giant deer and reindeer kept to open ground in herds, but most other deer were browsers of tree leaves. The solitary woodland moose were rare. They loved the summer leaves of deciduous trees, and the succulent pondweeds and water plants of marshes and lakes, and with broad hooves and long legs, they could negotiate marshy, boggy bottomlands. In winter they survived on the more indigestible grass, or high willow twigs of trees that grew on the low ground of river valleys, their splay-footed long legs easily carrying them through the windblown snow that drifted and piled up there.

Reindeer were winter-loving animals, feeding on lichens that grew on barren soil and rocks. They could smell the favored plants, even through snow, from a long distance, and their hooves were adapted to digging down through deep snows if they needed to. In summer they ate both grass and leafy shrubs.

Elk and reindeer both preferred alpine meadows or herbaceous highlands during spring and summer, but below the elevation of the ranging sheep, and the elk tended to eat grasses more than shrubs. Asses and onagers invariably preferred the arid higher hills, while bison ranged a bit lower, though they generally climbed higher than horses, which had a broader choice of terrain than mammoths or rhinoceroses.

Those primal plains with their complex and diverse grasslands sustained in great multitudes a fantastic mixture of animals. No single place on a later earth did more than approximate parts of it. The dry, cold environment of high mountains could not compare, though there were similarities. Mountain-dwelling sheep, goats, and antelopes extended their range to the lower ground then, but large herds of plains animals could not exist in the steep, rocky terrain of high mountains when the climate of the lowlands changed.