2 INTRODUCTORY 



SCOTLAND PARTICULARLY FITTED FOR OUR STUDY 



In some respects Scotland is particularly well fitted for 

 our study, mainly owing to its geographical situation and 

 geological history. In the first place man arrived at a 

 comparatively late date within its borders. There is no 

 evidence that the country was inhabited by the human race 

 until long after the period of rude stone implements, the 

 Old Stone Age, when man was already established in South 

 Britain and in the majority of the European countries in the 

 same latitude. His influence in Scotland, therefore, is limited 

 to the New or Polished Stone Period and succeeding ages, 

 distant enough though the first may seem to our modern 

 historical view. 



In the second place, Scotland has undergone, and in 

 comparatively recent geological times, an experience unlike 

 that of neighbouring countries. During the Great Ice Age, it 

 was completely buried beneath a continuous ice-sheet, some 

 3000 feet thick, which effectually blotted out its earlier plants 

 and animals. The Scottish flora and fauna are therefore 

 recent acquisitions due to the immigration of living things 

 when the ice-sheets were dwindling or after they had entirely 

 disappeared. Further, owing to the fact that Scotland has 

 for long been bounded on three sides by a broad sea, the 

 fauna with which Nature stocked her at the close of the Ice 

 Age has remained isolated, suffering, it is true, fluctuations 

 which Nature has ordained or man has induced, but un- 

 affected by that constant immigration and emigration except 

 in a few cases of the more mobile creatures, such as birds 

 to which continental countries are constantly liable. 



The original post-glacial fauna of Scotland may be 

 likened to a limited capital upon which man has traded. 

 So far as he has been satisfied with the natural interest of 

 the capital, the capital has remained as it was in the be- 

 ginning 1 , but this has seldom been the case. Often he has 

 trenched upon it, and at times so deep have been his 

 overdrafts that some items of the account have been seriously 

 diminished or exhausted. At other times he has added 

 afresh to the old capital, but in a new currency of his own 

 introduction. Could we but assess the original animal capital 



1 We are here ignoring natural fluctuations. 



