91热爆

In the Himalayas, the climatic conditions in the upper reaches of the Kali Gandaki valley influence what animals and plants can live there. The yellow throated marten, for example, has a fairly broad taste in food. It takes fruit and insects now and then, but relishes small rodents like mice and squirrels of which there are many. Even when winter comes and the forests are deep in snow, the marten will remain active. But it is a great traveller so if it gets very cold it will descend to lower altitudes for a while. The Himalayan bear, on the other hand, is able to live at very high altitude indeed. It has thick fur and its range is limited more by food supply than by temperature. It rarely tackles any animal larger than a mouse and survives mainly on ants, nuts, leaves, and grubs. So it seldom goes any higher than the forest can grow. At around 10,000 feet the rhododendron forest begins to thin as there is little rain the summer and it is too cold in the winter. Here it is only conifers that flourish in large numbers. The Kali Gandaki is still a very broad river at these altitudes and all summer long trains of mules trudge up the valley carrying barley and buckwheat to trade with Tibetans for wool and salt. All the way up the valley there are villages where the mule trains can rest. But during the summer few of them stop, preferring to keep going as long as there is daylight.