22 Introductory Biology 



ness of a specific problem may be stimulated (a) by a mere, general 

 curiosity, (b) by an actual need for the solution of the particular prob- 

 lem, or (c) by thinking or reading about a similar problem or situation. 

 After the problem or situation is clearly stated, the next step follows: 



B. The Formulation of Working Hypotheses Which Appear to Explain 

 the Problem and the Suggestion of Methods of Investigation 



lVorki?ig hypotheses may be considered as unproved assumptions, 

 hypothetical explanations, or reasonable speculations which at present 

 are without proof but which upon scientific investigation may be helpful 

 in securing the relevant information or data necessary for the eventual 

 solution of the problem. Undoubtedly, as the problem is being stated 

 clearly, one or more working hypotheses suggest themselves. No hy- 

 pothesis or probable cause, no matter how unimportant it may appear, 

 should be omitted. Each hypothesis is considered in turn, and either it 

 is rejected because evidence proves it to be faulty or it is investigated as 

 far and as scientifically as possible because it is giving reliable, pertinent 

 information with which to work. 



After all possible hypotheses have been made, the investigator must 

 determine the specific methods of investigation which should be followed 

 in order to secure reliable, pertinent information or data. In general, 

 methods of investigation include ( 1 ) accurate observations of facts and 

 phenomena, (2) controlled scientific experiments, (3) or a combination 

 of the two. The correct solution of the problem may be determined in 

 great measure by the use of the proper method of investigation. To 

 devise and use the latter properly may require broad practical training, 

 imagination, special techniques, or possibly elaborate and intricate ap- 

 paratus and equipment. If possible, the method of investigation should 

 be such that it may be repeated sufficiently to secure truly representa- 

 tive, typical results. In other words, the procedure should be such that 

 it can be checked and rechecked in order to reduce the chance effects 

 of unusual dififerences, or variations, found in a few instances or indi- 

 viduals. Limited observations, or too few investigations, especially if 

 not checked and rechecked, may give unreliable information. 



When using the experimental method of investigation it is highly 

 desirable to utilize, when possible, the so-called control group in which a 

 separate group of organisms or data is observed under conditions identi- 

 cal with the experimental group except that the one condition (rarely 

 two or three) being examined is not applied to the control group. These 

 so-called controls are extremely important in the experimental method 



