But, feral pigeons have adapted to life in cities, in suburban parks, on beaches and on farms. They have had established populations in North America for 200 years and on other continents for much longer. And despite this, their populations continue to have individuals of many different colors. They have never reverted to the colors of their wild relatives in the Mediterranean and beyond. No other feral animal has kept its domestic colors for more than a few generations.
Ecologists usually assume that the colors of organisms are somehow matched to their environments.
The fact that most feral species revert to one or two colors after several generations, helps to confirm the effects of environment on color. There are at least three possible explanations for why organisms match their environment. Alternatively, individuals of particular colors might be preferred as mates and thus have more offspring than those of other colors. A third hypothesis suggests that particular colors indicate dominance within a flock. When food is in short supply, such as in wild populations, dominant individuals will get more food and will be more likely to reproduce or have more young.