2 66 THE EVOLUTION OF SEX. 



killed, its mate is often found on the same spot a day or two 

 afterwards. 



Among birds and mammals, the greater differentiation of 

 the nervous system and the higher pitch of the whole life is 

 associated with the development of what pedantry alone can 

 refuse to call love. Not only is there often partnershi}), co- 

 operation, and evident affection beyond the limits of the 

 breeding periods, but there are abundant illustrations of a high 

 standard of morality, of all the familiar sexual crimes of man- 

 kind, and of every shade of flirtation, courtship, jealousy, and 

 the like. There is no doubt that in the two highest classes of 

 animals at least, the physical sympathies of sexuality have been 

 enhanced by the emotional, if not also intellectual, sympathies 

 of love. Those sceptical on this point should consult such a 

 work as liiichner's " Liebe laid Liebesleben in de?- Thierwelt ^^'' 

 which contains an overflowing wealth of instances. 



§ 3. Sexual Attraction. — Mantegazza has written a work 

 entitled "The Physiology of Love," in which he expounds 

 the optimistic doctrine that love is the universal dynamic ; 

 and from this Biichner quotes the sentence, that " the whole 

 of nature is one hymn of love." If the last word be used very 

 widely, this often repeated utterance has more than poetic 

 significance. But even in the most literal sense there is much 

 truth in it, since so many animals are at one in the common 

 habit of serenading their mates. The chirping of insects, the 

 croaking of frogs, the calls of mammals, the song of birds, 

 illustrate both the bathos and glory of the love-chorus. The 

 works of Uarwin and others have made us familiar with the 

 numerous ways, both gentle and violent, in which mammals woo 

 one another. The display of decorations in which many male 

 birds indulge, the amatory dances of others, the love-lights of 

 glow-insects, the joyous tournaments or furious duels of rival 

 suitors, the deliberate choice which not a few females exhibit, 

 and the like, show how a process, at first crude enough, becomes 

 enhanced by appeals to more than merely sexual appetite. But 

 it is hardly necessary now to argue seriously in support of the 

 thesis that love — in the sense of sexual sympathy, psychical as 

 well as physical —exists among animals in many degrees of 

 evolution. Our comparative psychology too has been too much 

 influenced by our intellectual superiority ; but while this, no 

 doubt, has its correspondingly increased possibilities of emo- 

 tional range, it does not necessarily imply a corresponding 



