WHAT IS EVOLUTION? 45 



and as such places afforded them much protection from 

 enemies and ample shelter for their nests and young, further 

 adaptations would occur, till the wonderful power of diving 

 and flying under water was acquired by a true land-bird. 1 



Here it will be seen that a bird, distinctly marked 

 off by important structures and habits from others, is 

 supposed to have originated from a different species 

 at some remote period, by efforts to obtain food in 

 what, to it, must have been an unnatural way ; and the 

 sole proof of this is the expression, we may well sup 

 pose. Why may we not as well suppose that all the 

 perching birds were at first like water-ouzels, which 

 would accord with the early appearance of aquatic 

 birds, and that they gained their diverse forms by 

 availing themselves of the better circumstances and 

 more varied food to be found in the woods and fields, 

 so that our water-ouzel may be a survival of a primi 

 tive type ? Neither theory can be proved, and the one 

 is as likely as the other, perhaps the latter, of the two, 

 the more likely, and neither actually explains any 

 thing. It is to be observed, also, as already hinted, 

 that the kind of evolution in this, as in some other 

 cases supposed by Wallace, is rather Lamarckian than 

 Darwinian. 



It is interesting to note that, though wedded to 

 that strange mode of reasoning of which the extract 

 above given furnishes an example, Wallace frankly 

 .and fully admits three of the great breaks in the con- 



1 Darwinism, pp. 116, 117. 



