Where did pigeons roost before Barns/Buildings were erected? I’ve never seen one in a tree.
I would think domesticated pigeons have always lived in barns and such. I can’t imagine why you’ve never seen one roosting in a tree, I’ve never seen one because I’ve never really looked for them in trees.
In the wild, the rock dove likes to roost on cliffs and rock ledges. When we built cities, we created a wonderful artificial habitat for them. Look at their approximate native range in that article.
Although Wikipedia redirects “rock pigeon” to “rock dove,” the official common name is now rock pigeon.