In the spirit of costumes and masks, I wonder about vanity in nature and birds. We are taught to keep emotions away from researching nature, as it clouds judgment and leads to assumptions.
However, as a photographer of natural things, I can make an exception.
I believe birds to be vain. Imagine to live on top of a mirror most of your time. Wading birds spend such a huge percentage of their days with their own reflections thrown back at them from the water's surface, it would make anyone anxious about appearance.
An ornithologist would explain the constant preening and fluffing as ways to keep parasites away. However, I've watched birds perform a ballet while pruning their feathers that could have been scripted by Stravinsky and no other feathered fellow was around. For what reason then, but vanity?