382 THE FUTURE OF ARID LANDS 
that the Western way of life and a mechanized culture are always 
a step forward to peoples now living close to a marginal existence. 
REFERENCES 
Specific references have been omitted in this paper. For questions of 
production physiology, the interested reader is referred to S. Brody, 
Bioenergetics and Growth, Reinhold Publishing Corporation, New York, 
1945; for water balance questions to K. Schmidt-Nielsen and B. Schmidt- 
Nielsen: Water metabolism of desert mammals, Physiol. Revs. 32, 135 
(1952). 
