“An inquisitive Cock Sparrow Asked every man in Wales, Why Parrots had long noses, and Foxes had long tails.

“Some said that Foxes used their tails In winter for a muff; And Parrots’ noses all were long, Because they all took snuff.

“But the reason, it seems to me, As perhaps it will to you, Is that they once had short tails, And short tails wouldn’t do.”

“Cock Sparrow”, a nursery rhyme taken from D’Arcy Wentworth Thompson’s “Nursery Nonsense”, or “Rhymes without Reason” (1864), is neither nonsense nor without reason.  Darwin, had he read it, would have smiled approvingly.