Exhibit in Chicago Natural History Museum 



Ruffed Grouse 



The muffled roll of the drumming of the ruffed grouse is one of the stirring songs of 

 the spring woods. Occasionally in autumn the drumming sounds through thicket and 

 copse, but then it is only a chance and fleeting thing. The drumming is the spring song 

 of the grouse, a song mechanically produced. How the grouse made this noise was long 

 a disputed question, but Dr. A. A. Allen settled it by taking motion pictures of a bird 

 in action and analyzing them. The sound is produced by the bird's wings striking the 

 air. Sitting on its display log, the bird moves its wings upward and forward, slowly, 

 then faster and faster, until they disappear in a blur, as the thumping blends into a 

 roll. 



The female, hearing the song, comes here to mate, and a display takes place. 

 Puffed up like a miniature turkey gobbler, the cock grouse, with ruffs erected, tail 

 raised and spread, and wings drooping, displays to the female. After mating, the 



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