1 64 ANIMAL ECOLOGY 



talk about " wading birds." Although it is possible to find 

 out a great deal about the food-cycles in animal communities 

 by working in terms of wider groups of animals than species, 

 yet it is essential for a complete understanding of the problem 

 to know the species of eater and eaten — a thing which we very 

 seldom do know. If the ornithologist or entomologist took 

 the small extra trouble of getting the foods accurately identified 

 down to species^ their observations would be increased about 

 a hundredfold in value. 



3. Although the number of observations about the food 

 and enemies of various animals is prodigious, yet the majority 

 of these data are just too vague to be of much value in making 

 a co-ordinated scheme of the interrelations of animals. In 

 other words, when one animal is seen eating another, it is very 

 desirable to record the exact names of both parties to the 

 transaction. The record of " green woodpecker eating flies " 

 is of some use, as is the record of " Woodpecker eating Borborus 

 equinus/* but the ideal observation is " green woodpecker 

 eating Borborus equinus.^^ This point leads on to another 

 important one, namely, the necessity for cultivating a proper 

 ** species sense." The extent to which progress in ecology 

 depends upon accurate identification, and upon the existence 

 of a sound systematic groundwork for all groups of animals, 

 cannot be too much impressed upon the beginner in ecology. 

 This is the essential basis of the whole thing ; without it the 

 ecologist is helpless, and the whole of his work may be rendered 

 useless, or at any rate of far less use than it might otherwise 

 have been, by errors such as including several species as one, 

 or using the wrong names for animals. The result of such 

 errors is endless misinterpretation of work, especially by 

 people in other countries. It is possibly to this danger that 

 we must attribute a certain lack of sympathy for ecological 

 work, politely veiled or otherwise, which is sometimes met 

 with among systematists. They realise that ecological observa- 

 tions are dependent upon correct nomenclature, and are 

 therefore to some extent ephemeral, in cases where the latter 

 is not yet finally settled. Added to this is the feeling that 

 ecologists are rather parasitic in their habits and are to 



