[4] Wild rock doves are pale grey with two black bars on each wing, whereas domestic and feral pigeons vary in the colour and pattern of their plumage.

[8] The rock dove was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Systema Naturae written by Carl Linnaeus.

[9] The genus name Columba is the Latin word meaning "pigeon, dove",[10] whose older etymology comes from the Ancient Greek κόλυμβος (kólumbos), "a diver", hence κολυμβάω (kolumbáō), "dive, plunge headlong, swim".

[12] The specific epithet livia is a Medieval Latin variant of livida, "livid, bluish-grey"; this was Theodorus Gaza's translation of Greek péleia, "dove", itself thought to be derived from pellós, "dark-coloured".

[3] The adult female is almost identical in outward appearance to the male, but the iridescence on her neck is less intense and more restricted to the rear and sides, whereas that on the breast is often very obscure.

[3] The white lower back of the pure rock dove is its best identification characteristic; the two black bars on its pale grey wings are also distinctive.

It is strong and quick on the wing, dashing out from sea caves, flying low over the water, its lighter grey rump showing well from above.

The noise of the take-off increases the faster a pigeon beats its wings, thus advertising the magnitude of a perceived threat to its flockmates.

A study of melanin in the feathers of both wild rock and domestic pigeons, of different coloration types and known genetic background, measured the concentration, distribution and proportions of eumelanin and pheomelanin and found that gene mutations affecting the distribution, amounts and proportions of pigments accounted for the greater variation of coloration in domesticated birds than in their wild relations.

[citation needed] Some sources state the species was first introduced to North America in 1606 at Port Royal, Nova Scotia.

[20] Although other sources cite Plymouth and Jamestown settlements in the early 17th century as the first place for species introduction in North America.

[29] Non-vocal sounds include a loud flapping noise at take-off, feet stomping, hisses, and beak snapping.

[29] Before the Columbian Exchange, rock doves were restricted to a natural resident range in western and southern Europe, North Africa, and extending into South Asia.

[1] Fossil evidence suggests the rock dove originated in southern Asia, and skeletal remains, unearthed in Israel, confirm its existence there for at least 300,000 years.

[29] Rock doves have a commensal relationship with humans, gaining both ample access to food and nesting spots in civilized areas.

[36] Current evidence suggests that wild, domestic and feral pigeons mate for life, although their long-term bonds are not unbreakable.

Pigeons breed when the food supply is abundant enough to support embryonic egg development, which in cities, can be any time of the year.

He approaches the female at a rapid walking pace while emitting repetitive quiet notes, often bowing and turning as he comes closer.

[42] Studies of pigeons in a semi-rural part of Kansas found that their diet includes the following: 92% maize, 3.2% oats, 3.7% cherry, along with small amounts of knotweed, elm, poison ivy and barley.

[43] Feral pigeons can be seen eating grass seeds and berries in parks and gardens in the spring, but plentiful sources exist throughout the year from scavenging (e.g., food remnants left inside of dropped fast food cartons, in the form of popcorn, cake, peanuts, bread and currants)[43] and they also eat insects and spiders.

Additional food is also usually available from waste bins, tourists or residents who feed bird seed to pigeons for reasons such as empathy, fun, tradition and as a means for social interaction.

As they do not possess an enlarged cecum as in European wood pigeons, they cannot digest adult plant tissue; the various seeds they eat contain the appropriate nutrients they require.

[51] With only their flying abilities protecting them from predation, rock pigeons are a favourite almost around the world for a wide range of raptors.

In fact, with feral pigeons existing in almost every city in the world, they may form the majority of prey for several raptor species that live in urban areas.

Peregrine falcons and Eurasian sparrowhawks are natural predators of pigeons and quite adept at catching and feeding upon this species.

The birds that prey on pigeons in North America can range in size from American kestrels to golden eagles[53] and may even include crows, gulls and ravens.

One study has shown that adult pigeons are not clinically susceptible to the most dangerous strain of avian influenza, H5N1, and that they do not transmit the virus to poultry.

[69] Other studies have presented evidence of clinical signs and neurological lesions resulting from infection but found that the pigeons did not transmit the disease to poultry reared in direct contact with them.

[73] Three studies have been done since the late 1990s by the US Agriculture Department's Southeast Poultry Research Laboratory in Athens, Georgia, according to the center's director, David Swayne.

In one experiment, researchers squirted into pigeons' mouths liquid drops that contained the highly pathogenic H5N1 virus from a Hong Kong sample.