Abstract
Pigeons are unique in the avian world. The late French ornithologist Dr. jean Delacour described the pigeon as "one of the most intriguing and heautiful groups of birds in the world. For years, Delacour himself kept a large private collection in Cleres, Normandy, France.
The many shapes and forms of pigeons and their various colors, from soft tans and grays to a spectrum of blues, reds, and yellows, are breathtaking. Pigeons and doves helong to the order Columhiformes, which includes the now extinct dodo.
There are approximately 300 species divided into two main groups, the seed-eating pigeons and the fruiteating pigeons. They are a fairly hardy and diverse family of hirds, and their ability to adapt has been used to measure how a taxon of animals acclimatizes to different environments. Pigeons are more widespread than parrots ranging throughout the major continents.
They also reside on the smaller isolated islands, particularly in the tropical regions. The only places on the planet that do not host at least one species of pigeon are the frozen polar caps. The most familiar to us, of course, are the ordinary feral pigeons found in our city parks, also commonly called Rock Doves Columba Livia.
In addition to species diversity, variation can exist within a pigeon species, according to geographical location. For example, the Rock Dove of peninsular India is darker in color than the same species in Europe. The unique differences between species of doves and pigeons are determined by the envi-
ronments they inhabit. Typically, hath the seed-eating and fruit-eating groups are arboreal, roosting, feeding, and nesting in the canopies of the world's forests. Some may never spend more than short periods of time on the ground. This applies to species such as the multi-colored, Black-naped Fruit Dove Ptilinopus melanospila of southeastern Asia. Such arboreal forms must adapt in order to coexist with potentially harmful species. Monkeys, for example, would certainly he a threat to the adult birds and catastrophic to squabs and eggs.
Some birds that live in regions with primates have developed different strategies for propagation. The adaptive strategy was to become more terrestrial; feeding hahits were influenced and the birds eat fallen fruits and seeds. The terrestrial pigeons even began to nest on the ground or in low, inconspicuous shrubs and hushes. A few species such as the Wonga Columba melanoleuca of eastern Australia and the Victoria Crowned Pigeon Goura uictoria of Papua New Guinea have also adapted to a more terrestrial life-style.
Other differences in the pigeon characteristics affected by evolution are the various plumage. Pigeons and the smaller doves display many beautiful colors and patterns. The vivid colors. as well as the duller shades of grays and browns, provide cryptic cover for the hirds. Ornithologist Derek Goodwin explains that "because they are usually preyed upon by avian predators such as hawks and falcons, smaller species of pigeons tend to be more cryptic in color than the larger species." The inconspicuous grays and browns of such species as the insular Mauritius Pink Pigeon Columba mayeri aid in the cryptic camouflage that is important for their survival. Other adaptations evolved in species such as the extinct Passenger Pigeon Ectopistes migratorius of the Americas, which developed long wing and tail feathers. Goodwin theorizes that "The purpose of the elongated wing and tail feathers of pigeons is as a direct correlation to regular migrations and birds with enlarged territories that are defended. "
In contrast to the less colorful Columbiformes are the species that inhahit the deep forests of the world, particularly Asia and Australia. Many ornithologists consider these pigeons the very essence of color. For each species, the colors are used as a method of recognition. Colors are also utilized in aggressive posturing among and hetween species and in courtship displays. Markings and colors are also a form of defense against unwelcome intruders. By flashing bright colors and patterns, pigeons can startle a predator for a split second, allowing the hird to escape. Aggressive displays can also he used to intimidate con-specific males that are...