Again, the witty Bro. Darwin catches an unforgettable scene:  “The males (English Pouter pigeons), especially when excited, pout more than the females, and they glory in exercising this power.  If a bird will not, to use the technical expression,”play,” the fancier, as I have witnessed, by taking the beak into his mouth, blows him up like a balloon;  and the bird, then puffed up with wind and pride, struts about, retaining his magnificent size as long as he can (Darwin 1897, 143) .”

Bibliography:

Darwin, Charles.  The variation of animals and plants under domestication, Volume I.  New York:  D. Appleton and Company, 1897.

Resources:

Darrell Barnes Science and Nature YouTube Channel