Years ago, when magic was still a part of everyday life, dogs flew. They filled the skies with their long, feathery wings and howling (which could get annoying, but oh well). It was a wonderful site, and a basic commonality of everyday life. Not to mention, the dogs were kind souls, so everyone was happy that they were the ones to receive the gift of flight.
Or so everyone thought. One day, the pigs decided that they deserved the gift of flight far more than those mangey mutts (excuse me for the language). They wanted wings for themselves. So they went to the birds (who did not have wings yet, of course) and asked them for help. The birds refused to help the pigs because they knew the dogs were good animals. So the pigs stormed off and decided to trick the dogs on their own.
The pigs went to a sorcerer (who was very powerful, but a bit ignorant and new to the job) and told him that the dogs were having trouble with their wings. They said the wings weren’t working quite right, but they couldn’t figure out what was wrong while they were on the dogs’ bodies. The sorcerer was troubled by this, and agreed to cast a spell to remove the wings of all the dogs so that they could take a look at them.
When the dogs landed on the ground to settle in for the night, the sorcerer cast his spell, and all of the dogs’ wings fell off. The dogs howled and barked in surprise and fear as their wings (which were no longer their wings; the sorcerer didn’t realize, but the wings could not be reattached) were magically whisked away. They chased their wings to the sorcerer’s house and the lead dog (what type of dog was he? A labrador, of course. A labrador with a coat of gold, because he was basically the king) entered on the behalf of all the dogs in the world.
The dog asked what was going on and the sorcerer explained. The lead dog told the sorcerer that the dogs’ wings had been working fine. It dawned on them what had happened, and they turned to the lead pig (yes, there’s also a lead pig; he’s bright pink, which is where the stereotype of what color pigs are comes from), who was trying to attach the wings to his own body (which was possible because they needed a new owner and could not go back to the dogs, but it could not be done without magic, so the pig wasn’t getting anywhere).
The pig realized that his plan had failed and tried to defend himself, but the sorcerer would have none of it. He cast a spell on the pig (a very powerful spell that he was certain he knew everything about) that made it so that no pig would ever be able to fly (at least, not on their own). The pig screeched in anger and rampaged around the house, but the sorcerer cast him out and far away (to a farm, to be precise, which is why pigs are now known as farm animals).
With the pig gone, the lead dog was able to properly mourn for his lost wings. The sorcerer apologized, for there was nothing he could do to help him. As they sat in their mourning, a bird (there’s no lead bird, they only have a Council) hopped in, breathing heavily from the exhaustion of walking so far on its little feet. It told the sorcerer and lead dog about how the pigs tried to get the help of the birds (how the pigs thought the birds could help, the world may never know) and how the birds were sorry they hadn’t made it in time to warn them. If only they could move faster…
The sorcerer and dog looked at each other and grinned. The lead dog turned to the bird and offered to give all of birdkind (blackbirds, hummingbirds, geese, and all the rest) their lost wings. The bird was shocked and wouldn’t accept the gift at first, but (upon hearing that the dogs could not have their wings back and there was no one else they wanted to give them to) ended up accepting.
The sorcerer cast his spell, and the wings attached themselves to all of birdkind. The bird who had entered flapped its wings in wonder, but didn’t know how to use them. It asked the dog, but the dog didn’t know. They never had to learn how to fly. They just knew from birth. So the bird hopped to the window and jumped out (why it thought that would be a good idea, the world may never know). The lead dog and sorcerer yelled in fear, but were stunned to see the bird flying like it had had wings its whole life (this is why birds hop out of trees without question when learning to fly).
From that day forward, all birds had wings, dogs lived on the ground (and as household pets, a tradition that the lead dog started with the sorcerer), and pigs were cursed to never fly on their own. This is why people say “when pigs fly” when they think something will never happen.