66 BIRD LIFE GLIMPSES 



kind of the artificial structures made by it. It is, 

 indeed, obvious that the " bower," in many cases, 

 could not be quite what it is, if it had also to answer 

 the purpose of a nest, and still more so, perhaps, 

 that the nest could never have made a good bower. 

 The extra structure, therefore, represents a greater 

 capacity for doing a certain thing just as do the 

 extra limbs which makes it likely that it has been 

 evolved from the earlier one, in accordance with the 

 same general law which has produced the latter. 



Thus, in our own rook we see, perhaps, a 

 bower-bird in posse, nor is there any wide gap, but 

 quite the contrary, between the crow family and 

 that to which the bower-birds belong. "The 

 bower-birds," says Professor Newton, " are placed 

 by most sy sterna tists among the Paradiseid<e" and 

 Wallace, in his " Malay Archipelago," tells us that 

 " the P aradiseidte are a group of moderate-sized birds 

 allied, in their structure and habits, to crows, 

 starlings, and to the Australian honey-suckers." It is, 

 surely, suggestive that the one British bird that uses 

 its nest or nests, collectively as a sort of recreation 

 ground, where the sexes meet and show affection, 

 during the winter, should be allied to the one group 

 of birds that make separate structures, which they 

 use in this same manner. Of course there are 

 differences, but what I suggest is that there is an 

 essential similarity, which, alone, is important. Pro- 

 bably the common ancestor of the bower-birds was 

 not social in its habits like the rook, and this 

 difference may have checked the development of the 

 bower in the latter bird. As far, however, as the 

 actions of the two are concerned, they do not appear 



