Have you ever tried feeding the city birds? If you have, you might have already noticed that a majority of the birds you are feeding are going to be pigeons. This says three things about these birds: one, that pigeons are pack or social birds; two, that they are to an extent comfortable around humans; three, they are fucking everywhere! The pigeons we commonly see in all the world cities originate from the rock dove, usually encountered living in the rocky environments of southern Europe, south Asia and north Africa. Unlike city pigeons, wild rock doves don't have a varied plumage. The reason why the city pigeons do in comparison to their cliff dwelling relatives can be attributed to the domestication of pigeons. It's possible that the earliest we domesticated pigeons was around 10 000 years ago. At first they were kept as a source of food (the chicken was domesticated somewhere around 8 000 years ago), but after recognizing their speed and ability to navigate back to their home no matter the distance they were from it, we started keeping them as messengers (homing pigeons). There are a bunch of theories on the reason as to how they are able to navigate back to their home, won't be explaining each and every one but here's a few:

Ancient people made what essentially were homes/huts for pigeons (Dovecotes) usually built to collect the eggs and poop, and as a status symbol. Some might have even requested that a dovecote be made on their grave. Eggs are probably a sensible reason to keep a pigeon (considering that the pigeons themselves were eaten) but to be raised because of their feces arises a few questions. The answer to the most commonly asked question is: it's a really good fertilizer. Around the 17th century (correct me if I'm wrong about the number) pigeon shows/exhibitions and races gained popularity and now everyone was in some kind of pigeon association. This hobby is still active but lost the popularity it had around the start of the 20th century. Ever seen a pigeon with a big, "buff" chest or chicken like tail feathers? Thank the pigeon fanciers for that. I don't know a lot about these events and can't say based on what criteria makes a pigeon worthy enough to be a winner. There are videos and articles about this if you're interested though. We usually see people keep parrots or we see them in zoos, so we think that parrots also count as domesticated animals, but that in fact is not the case. The earliest record of us keeping parrots as pets only dates about 5 000 years ago. And though technically that is enough time to domesticate an animal, parrots were treated differently than pigeons and chickens and so don't count as domesticated. We can see that in the appearance when comparing a pet bird to a wild or feral one. A pet budgie won't have a distinct difference to a wild one and isn't classified as a different breed, but a pet or feral pigeon is visually different to a rock dove. Compare a dog to a wolf. I'd love to have a pigeon of my own, they're so cute and smart. All the interactions I've had with city pigeons were so great. I've had one sit on my shoulder as I was feeding others and it felt so cool. I probably looked crazy from the outside (I had people record me lol); on the inside I felt like a medieval assassin with a hawk on my shoulder. They're the softest balls of feather I have had the pleasure to touch. Obviously it's hard to pet a city pigeon, but they have the tendency to bend down low enough when feeding of my hand so that the feathers around their neck graze my fingers. Everyone already knows the pigeon coo, whether or not it's if you saw one chasing around another pigeon, trying to impress it or woke up to one sitting by your window. And it's just the sweetest sound ever. After a while of me feeding one from my hand, he would start to coo. I don't know what it means, but I take it as appreciation for the food. (He could be cursing at me, but then again, I wouldn't be able to understand.)