Dogs and Birds

I have just seen something rather beautiful.
            On the playing field near our house, I saw a dog chasing a bird.  The dog, a big German Shepard was running, at full tilt (head down, tail flat) after a pink galah.
            It didn't look good - the galah was in a flat sprint and the dog was gaining.  The dog drew level and snapped his head up at the body of the bird, and then, suddenly he shifted gears and his predatory race turned into a springing lope and the bird leveled out in flat glide and they stayed there, together and I realized - They were playing.
            I stood and watched.  The bird circled round and set down perhaps 20 meters from the dog and the dog would put up his head and gallop flat out and the bird would lift off - but never higher than the height of the dog's shoulder and as the dog caught up with it, they'd glide together until the bird had to flap its wings to regain altitude - or land. 
            They must have done it seven or eight times while I watched, until the bird tired and lifted off and settled in a tree.
            The poor dog was left with no companions but a small crested dove - who did not react with quite so much...equanimity... to his overtures. (An explosion of feathers and a torrent of screeched profanity was about what happened after that.)