THE INFLUENCE OF THE HIGH PLATEAUS 109
species I am well aware, but those mentioned are enough to show the general character. The names of the plants were originally recorded with no thought of their possible significance. The list is of interest in view of the much controverted theory that Central Asia was the original home of the chief races of Europe. So far as it goes, it supports the theory; for it suggests that the original migrants from Central Asia carried with them plants which there grow wild, and which have since been cultivated in the new lands where the wanderers finally settled.
Returning to our main subject, the first and most important geographic feature of the Tian Shan plateau is, as we have seen, the pamirs, or plains of rich grass. They determine the character of animal life, including man. The climate is so cold, and snow lasts so long, that animals cannot permanently inhabit the plateau in great numbers, unless they hibernate like the innumerable marmots, or migrate like birds; and even the latter cannot find food easily because of the scarcity of insects and of weeds with large seeds. Yet during the summer months the conditions are almost ideal for herbivorous species of animals. Man can easily turn this fact to his advantage, provided he adopts the habit of permanent nomadism. The rich, grassy uplands are capable of fattening millions of sheep and cattle during the summer; but before the winter snow sets in, the flocks must be driven many days' journey down to the dry open plains, or to protected valleys, in either of which places the animals find poor picking compared to their rich summer pasture. The Khirghiz shepherd must change his residence at least twice a year. His family must go with him. All the
IIIFカラー高解像度
