COURTSHIP AND SEX 201 



species (see Karl Pearson, " Grammar of Science," 2nd ed. 

 1900, p. 418). 



(F) At this point attention may be directed to the im- 

 portant contributions to the natural history of mating to be 

 found in H. Eliot Howard's monumental " British Warblers " 

 (1907-19 1 5). We venture to think that this acute and 

 sympathetic observer exaggerates the instinctive at the 

 expense of the intelligent element in the behaviour of birds, 

 and that he is unnecessarily antagonistic to Darwin's theory 

 of sexual selection, but his work is a rich treasure-house of 

 reliable data. It is of great interest, for instance, to discover 

 how much competition there is among the male warblers, 

 before the females arrive on the scene, in the way of discover- 

 ing and securely holding the most advantageous territories 

 for nesting. Not less important is the evidence that the 

 soberly coloured warblers do not fall behind brilliantly 

 coloured birds in the elaborateness and abandon of their 

 display attitudes and poses. The importance of Bird Terri- 

 tories has been recently emphasised by Mr. Howard in a 

 separate volume (192 1). 



(G) Darwin was well aware of many of the difficulties 

 besetting his theory. With his wonted candour he antici- 

 pated various objections, e.g. that the theory " implies powers 

 of discrimination and taste on the part of the female which 

 at first appear extremely improbable " (" Descent of Man," 

 p. 326). The first very serious criticism came from Wallace 

 in 1871, and was restated in his *' Darwinism" in 1889. 

 The most elaborate criticism as yet is surely to be found in 

 T. H. Morgan's " Evolution and Adaptation " (1903), where 

 no fewer than twenty-four reasons are given for rejecting the 

 theory. Within our narrow limits we must confine our 

 attention to the three criticisms which seem most important. 



There is, in the first place, an admitted difficulty in the 

 scarcity of direct evidence that some of the males are actually 

 disqualified and left unmated. If all the males get mates 

 sooner or later, then no discriminate elimination is effected. 

 Professor Karl Pearson has given statistical evidence of 

 preferential mating in mankind, but this is hardly procurable 



