Bird Architecture 



gradual addition of grass, leaves and feathers to give 

 comfort as well as to retain warmth, were certain 

 marks of progress. 

 Even before the 

 days of the steam 

 plough or the mow- 

 ing machine, the 

 birds' Juggernaut, 

 there were ten 

 enemies of the 

 nests on the ground 

 to one in the trees; 

 and it did not take 

 very highly devel- 

 oped birds to per- 

 ceive that the 

 perches on which 

 they themselves 

 sought safety from 

 snakes, rats, mice 

 and the larger prowling animals, might support a 

 nursery. Fear has ever been a powerful spur to 

 achievement. Stiff sticks, unyielding twigs that by 

 no possibility could be woven into a cradle were 

 simply piled in loose heaps on the limb of a tree ; 

 yet these crude lattices mark the first step in the 

 evolution of bird architecture. On such bare slats 

 the young of herons, egrets, pigeons, doves, cuckoos 

 and many other birds that come into the world 

 naked or with a thin coat of down, at most, to 

 protect their tender flesh must spend an unusually 

 long and helpless babyhood. Quite naturally, then, 

 the next step forward was to carry the mattress of 



41 



Photograph by Carlin 



The song-sparrow's grassy cradle 



