I'm running through Un'goro trying to finish off the "To all the critters I've loved before" achievement, looking desperately for a parrot, and bombing out. Suddenly, my sweetie, who was watching over my shoulder, yelled "THERE'S ONE!"
Parrot, Pterrordorax ... both have wings, right?
"And," I added, "they both begin with the same letter!"
This was not taken in the spirit offered. :)
Incidentally, the comments on WoWHead indicate that if you kill snakes, parrots will spawn in their place. So much for my "egg" theory. But, I dutifully killed off every snake I saw, and when I returned to my starting point, a parrot was flapping around in the same location ... so there might be something to it.