Only the mynas

 I've oft times seen the mynas pause as they walk and fluff, a behaviour that seems peculiar only to these mynas.

A bird would fluff up its feathers to cool down on a hot day, to release excess body heat (as it would on a cold day to keep warm).  It's also said that it does this when excited or when it wants to attract the female!

And it fluffs up too when it preens to get rid of excess water or dust or dirt.

Perhaps these mynas take to the ground too much (the only other birds that walk the ground as much are the doves but they do not seem to exhibit this behaviour), attract too much dust and dirt, and frequently desire to dust off!

The Javan Myna

The Common Myna