BIRDS AND THE WEB OF LIFE 409 



This post-glacial fauna affords a good starting-point 

 for an inquiry into the effect of man's hand upon animal 

 life, and this inquiry has been conducted in a masterly 

 way by Dr. James Ritchie in his great book, " The Influence 

 of Man on Animal Life in Scotland " (1920). The post- 

 glacial fauna was the capital with which prehistoric man 

 started, to which he added various acquisitions from abroad, 

 and into which, at times, he dipped heavily. What were 

 the changes as far as birds are concerned ? 



Among deliberate changes, the first place must be given 

 to domestication, which included poultry and pigeons. 

 The direct effects on the structures and functions, habits 

 and temperaments of the animals domesticated (e.g. horse 

 and cattle, sheep and dog) were so great that man's role 

 became almost like that of a creator, though in actual fact 

 he has never done more than sift and shuffle the novelties 

 which creative evolution supplies. Domesticated birds 

 shared in this transforming. But to feed and protect his 

 stock man operated largely on the country, and this brought 

 about far-reaching changes, which affected wild birds as 

 well as wild beasts. 



But domestication almost necessarily leads to a destruc- 

 tion of wild life, for although flocks and herds lighten the 

 earlier task of hunting for food, there rises a new need for 

 restricting the enemies of the domesticated stocks. The 

 larger carnivores are hunted down, and such fine birds 

 as eagles. There is a persecution of the smaller beasts of 

 prey, such as wild cat, polecat, and pine-marten, and of 

 hawks and owls. The regret is not only scientific and 

 aesthetic, but economic as well, for the destruction of the 

 carnivore means the increase of the rodent ; and the multi- 

 plication of rats and mice and voles involves losses which 

 have to be set against the increased safety of, let us say, 

 the poultry yard. 



In old days many wild birds were killed for food, and 

 on the Baltic shores to-day we may see the salting of barrel- 

 fuls of crows. Other birds were used for their fat and 

 feathers, and so forth, and a distinction must be drawn 



