Some Bird Architects. 



from view. This point is confirmed by the fact that 

 the Rock Dove does make an almost exactly similar twig 

 nest in such a situation. We may safely suppose that 

 in ages to come the Wood Pigeon and Turtle Dove 

 will gradually acquire the necessary skill to construct 

 the kind of nest which Nature demands of all nest- 

 building birds that build in the more open situa- 

 tions they have chosen for the safety of their offspring, 

 and that their eggs will also become coloured, and there- 

 fore less conspicuous objects. 



As a matter of fact, there is a great deal to be learned 

 of the amount of progress, or rather I should perhaps 

 say divergence from the ancestral type, by the care- 

 ful examination of the colour of the egg in conjunc- 

 tion with the structure and shape of the nest in which 

 it is deposited, and the nesting site. Probably the eggs 

 of all birds were first of all white and unspotted, like 

 those of their reptile ancestors ; but only those birds 

 which have continued to nest in deep safe holes have 

 been able to continue laying such conspicuous eggs 

 those which breed in more exposed situations having 

 of necessity developed on their eggs patterns of colour 

 which in the course of time have become more or less 

 imitative of the colouring of their surroundings in pro- 

 portion to the greater or lesser need for this kind of 

 protection, according to the character of the particular 

 nesting site selected. 



The Crow's nest shows a considerable advance in 

 the art of nest construction over that of the Wood 

 Pigeon, though of rather rough, untidy appearance. 

 The foundation is of sticks roughly tangled together, 

 the character of the workmanship varying among the 



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