CHAPTER XI 



METHODS 



There are several points about methods which (i) are of general importance 

 in ecological work, e.g. (2) the recording of facts with an eye to the use 

 to which they will be put in the future, and (3) the correct identification 

 of species, which latter depends both (4, 5) upon a pleasant and com- 

 prehending attitude of systematists towards ecological work and (6) 

 upon the collection of good systematic material by ecologists, who alone 

 can provide the right data with the specimens. (7) The usual mistake 

 among beginners is to under-estimate the number of animals of each 

 kind. (8) Information from other people can be of great value if backed 

 up by specimens of the animals concerned. (9) The carrying out of a 

 biological survey involves various things : first, the listing of the main 

 habitats, then (10) the collecting of the animals, together with careful 

 habitat- and other notes, and finally (11) the construction of food-cycle 

 diagrams, which (12) necessitates exhaustive study of the food habits 

 of animals, a study which can be made in at least ten ways. (13) The 

 community-relations of animals can be worked out in two ways, either 

 separately or combined together. (14) The numbers of animals require 

 special methods for their recording : one may use censuses in a given 

 area or (15) in a given time, while (16) for recording variations in numbers 

 it is advisable not to refer to " the usual " as a standard, but (17) to the 

 numbers in the previous year or month, etc. (18) Finally, in publishing 

 the results of ecological surveys it is desirable to include an index of 

 species or genera, and (19) to employ certain special methods for 

 recording the facts about food, etc. 



I . Although the whole of this book is really concerned with 

 methods of tackling ecological problems, rather than with 

 an inexorable tabulation of all the important facts which are 

 known about ecology, it is advantageous to draw together all 

 the various lines of thought into one chapter, and to mention 

 a few general ideas which may be of use as a background to 

 ecological work. One of the most striking things about 

 natural history facts is the haphazard way in which they are 

 usually recorded. We are not referring so much to the fact 

 that our knowledge of so many life-histories of animals has to 

 be built up by piecing together fragmentary observations of 

 different people, since it is impossible for any one person to be 



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