754 Causes and Course of Organic Evolution 



In characterizing this fourth group as "phytivorous, peace- 

 ful, and social," we by no means overlook the fact that san- 

 guinary sexual fights often occur between individuals — as with 

 deer, bulls, horses, etc. — or between groups from separate col- 

 onies of the same species — as with ants, with pigeons and other 

 birds — or between two phytivorous families as with locusts 

 and some ants. Such are well known cases, and the results 

 at times are terribly destructive to the species, as all can testify 

 who have witnessed a one or two days' warfare amongst red 

 ants from separate colonies. But even here the food question 

 seems mainly to be the cause of strife. The comparative 

 rarity however of such happenings, and the general social 

 tendencies of life, are helpful factors for this fourth group. 



If we return now to a more detailed study of the first group, 

 it may truly be said that it includes "the merciless compet- 

 itors" of the animal kingdom. The qualities already noted 

 are fairly or even keenly and highly developed. But these 

 qualities are limited in range, and are concentrated on the 

 main issue of securing food by competitive destruction of 

 animals as large as, or larger than, themselves. Now, if keen 

 and merciless competition is the successful method for ensur- 

 ing continued existence, and is also the best means for multi- 

 plying any species, the above carnivorous and competitiA'e 

 groups should constantly lead in the race of life, and should 

 "survive" most perfectly in the struggle for existence. But 

 we venture to assert that the opposite is undoubtedly true. 



Before adducing proofs of this, however, it may be well to 

 again point out that the three prime factors in animal as in 

 plant life that ensure evolutionary "success" are successful 

 vegetation (including successful food supply that is neither 

 too abundant nor too scant), also sufficient defense against 

 attack, and fairly abundant means of reproduction. So long 

 as a couple of individuals or a species can maintain a course 

 of living that fulfills these requirements, they remain success- 

 ful, or even may tend to become dominant. 



Now in such requirements the first group is handicapped 

 along several lines. The prey becomes increasingly wary; they 



