450 SECTION H. 



of animals which are attributed to aridity, rarefied air, soil, 

 etc., are adaptations due to avoidance of dangerous rays of 

 light. This is to be noticed in the habit of some delicate plants 

 which thrive in the shade of hardy plants, the protective cover- 

 ing and nocturnal habits of animals, and the architecture and 

 shelter instincts, as well as skin color of the ancient and modern 

 Indians who lived in caves, cliff shelters, or cavate houses, 

 or whose pueblos as a whole or as to the individual houses 

 were constructed to admit a minimum of light. 



But from far different causes, though still environmental, 

 pueblos were generally oriented with reference to the east ; first, 

 for the utilitarian purpose of receiving the early morning sun, 

 grateful after the chilly nights of the high regions; and second, 

 on account of the importance of the rising sun in heliolatry. 



It is difficult to realize the immense modification of animal 

 and vegetable life which the white man has wrought in this 

 region during the thirty years of his active occupancy. At the 

 beginning of this period the region was well grassed and sup- 

 plied with other vegetation adequate to the needs of vast herds 

 of antelope, elk and deer ; rodent animals and birds were plenti- 

 ful, and carnivores had abundance of prey. As a result of vege- 

 tation a humus had formed on all protected situations, rainfall 

 was absorbed and equalized in distribution and the terrific 

 denudation which gashes the land at present was not begun. 



The country was adapted to grazing and especially favorable 

 on account of temperature and latitude, and at once great herds 

 of cattle, horses and sheep were introduced from Texas where 

 the range had failed. The result was that the range became 

 overstocked, the grass disappeared under the tongues and hoofs 

 of myriads of domestic animals, shrubs and trees were browsed 

 and destroyed or swept away by fires, from certain regions 

 species of plants vanished, and the land lay bare to the aug- 

 mented winds and torrential rains. Trails became profound 

 arroyos and the humus vanished in the streams and the surface 

 of the country was stone, sand and gravel. Not the least of 

 this baneful influence was the drying up of springs and other 

 sources of water, and more than one observer collected data 

 going to prove the progressive desiccation of the Pueblo region . 



