INTRODUCTION 7 



history; and a knowledge of this history is as useful in accounting for its 

 present content and tendencies, as is the history of a nation in under- 

 standing its present institutions and policies. 



Conditions of Early Biology. — One who reads of the early ideas re- 

 garding animals is apt to conclude, unless warned in advance, that the 

 science of zoology was much better developed among the early philoso- 

 phers than it really was. The list of early writers who published bio- 

 logical doctrines is a long one, and unless it is pointed out that many of 

 these doctrines were but a very small part of the works in which they were 

 contained, and that the authors were often chiefly interested in religion, 

 or theology, or astronomy, with their biological concern largely incidental, 

 an exaggerated idea of their importance may be gained. When to this 

 consideration is added the fact that these writings were often based, not 

 upon observation or experiment, but upon speculation, anecdotes, rumor, 

 or superstition, conservatism in appraising early zoology is more than 

 ever necessary. 



Although the ancient knowledge of animals was of little value in 

 comparison with the zoology of today, the early students of the science 

 should be regarded with lenience. Their advantages were meager. 

 They could not be taught the subject, for they were pioneers. ;• A sopho- 

 more now may know more about animals than did Aristotle, even though 

 in intellect he would appear, beside Aristotle, as a candle to the sun. Nor 

 could the pioneers easily remedy their benighted condition, since the 

 absence of microscopes and other equipment closed to them many of the 

 doors of investigation that are open now even to elementary students. 

 Hence, while recognizing that ancient zoology was a very inferior science, 

 as judged by modern standards, the early zoologists must not be too 

 harshly criticized. As will be seen, the best of them are to be credited 

 with accomplishments which, in view of their handicaps, were truly 

 remarkable. 



The Early Greeks. — The earliest zoological writings that are known 

 were produced by the Greeks. It is certain that these were not the ear- 

 liest works, since they contain references to the "ancients," but they are 

 the earliest that have been preserved. The earliest writers can hardly 

 be called zoologists. Often they were distinctly something else, even 

 poets, and their shortcomings in biology need occasion no surprise. The 

 early Greeks were inclined to the deductive method. They reached a 

 conclusion quickly, with little evidence to support it, and then applied 

 their generalization to discover what other things ought to be true. 

 Naturally, if the generalization was incorrect, and it was likely to be 

 incorrect, its application led to fallacies. 



Surrounded as Greece is by warm waters, teeming with life, the 

 country furnished abundant material for observation of animals. Some 

 advantage was taken of this opportunity, or Greek writers would hardly 



