THE VALUE OF ECOLOGICAL SURVEYS 25 



and responses to their environment before they 

 have become too much changed or exterminated. 

 This is a duty to future naturalists and to future 

 science. The animal remains in themselves are only 

 a very incomplete record ; their activities and en- 

 vironments are an essential part of the animals and 

 should also be preserved. 



The study of original conditions is a simpler prob- 

 lem than after interference by man, but excessive 

 modifications result in the simplicity due to an- 

 nihilation and a corresponding imperfection of 

 knowledge. The value of a knowledge of original 

 conditions tends to increase with time, and will aid 

 much in future interpretations when there is still 

 more disturbance. Thus an important perspective 

 may be developed which will aid in estimating 

 relative values. At the present time the loss of 

 records of original conditions is only beginning to be 

 felt. The possibility of making certain records will 

 vanish with each generation. It is not even desirable 

 to preserve all, but it is evident that many ecological 

 records should be preserved. 



As the importance of ecological studies, in natural 

 environments, comes to be more generally recognized 

 the serious encroachments of civilization upon habitats 

 and associations is enforced upon us. Not only 

 are the descriptions of these associations very few 

 in number, but the interrelations of the animals in 

 them are even less known, and the chances of pre- 

 serving adequate records before their complete ex- 

 tinction are becoming fewer every year. Without 



