APPENDIX 



Methods of Study 



Methods used in the study of environment, while not new, involve 

 the methods of several sciences. To determine the gross features, the 

 methods of dynamic and historic geology and physiography, or of plant 

 ecology, must be applied. For further analysis the methods of meteor- 

 ology and special methods for measuring the environment physically 

 and chemically must be employed, where other sciences have given us no 

 data and method (see Clements). These consist of methods of studying 

 the rate of evaporation, water content of the soil, and the application 

 of meteorological methods to climatic details. The special chemical 

 methods, aside from chemical methods of the study of the soil, consist 

 of detection of the presence of excretory products in the soil or water. 

 The best discussion of special methods is given in the references (35a, 43, 

 6o> 74, 76, 77, HI, n8, 121, 124, 125, 129, 130, 131). 



METHODS OF STUDYING ANIMALS IN THE FIELD AND LABORATORY 



a) Observation. — One important thing in ecological study is simply to 

 sit quietly and watch animals, and record what they do. This requires 

 much time, and the best observers often sit for hours before making the 

 desired observations, but the reward is always adequate. Some good 

 ecological knowledge has thus been acquired. One difficulty is encoun- 

 tered in this work. When the observer is watching one animal whose 

 actions are not of especial interest at that moment another animal often 

 suddenly appears and does something which seems of importance or 

 which is of especial interest. The observer's attention is diverted from 

 its original object of observation. " Which shall I continue to watch ?" 

 is often asked by the student. No definite rules can be laid down. In 

 general it is probably better to follow the original object. The answer 

 depends entirely upon the relative ease with which the two animals before 

 the worker can be observed. The beginner cannot answer this question 

 and only experience can decide which should be followed. 



b) Experimentation. — Investigation in ecology requires, in prepara- 

 tion, long training in both the biological and physical sciences. Persons 

 not possessing such training cannot hope to make important contributions 

 to the science. Ecology is a field often requiring very complicated 

 experimental methods. Animal behavior and some aspects of physiology 



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