The domestic pigeon (Columba livia domestica) is a pigeon
subspecies that was derived from the rock dove (also called the rock pigeon).
The rock pigeon is the world's oldest domesticated bird. Mesopotamian cuneiform
tablets mention the domestication of pigeons more than 5,000 years ago, as do
Egyptian hieroglyphics.Research suggests that domestication of pigeons
occurred as early as 10,000 years ago.
Pigeons have made contributions of considerable importance
to humanity, especially in times of war.In war the homing ability of
pigeons has been put to use by making them messengers. So-called war pigeons
have carried many vital messages and some have been decorated for their
services. Medals such as the Croix de guerre, awarded to Cher Ami, and the
Dickin Medal awarded to the pigeons G.I. Joe and Paddy, amongst 32 others, have
been awarded to pigeons for their services in saving human lives.
Reproduction
Domestic pigeons reproduce in a similar way to the wild rock
pigeon. Generally humans will select breeding partners. Crop milk or pigeon
milk produced by both male and female parent birds may occasionally be replaced
with artificial substitutes. Pigeons are extremely protective of their eggs,
and in some cases will go to severe lengths to protect their productive eggs
and have been known to seek revenge on those who interfere with their
productive process. Baby pigeons are called squeakers or squabs.
Homing Pigeon
Trained domestic pigeons are able to return to the home loft
if released at a location that they have never visited before and that may be
up to 1000 km away. A special breed, called homing pigeons has been developed
through selective breeding to carry messages and members of this variety of
pigeon are still being used in the sport of pigeon racing and the white release
dove ceremony at weddings and funerals.
The ability a pigeon has to return home from a strange
location necessitates two sorts of information. The first, called "map
sense" is their geographic location. The second, "compass sense"
is the bearing they need to fly from their new location in order to reach their
home. Both of these senses, however, respond to a number of different cues in
different situations. The most popular conception of how pigeons are able to do
this is that they are able to sense the Earth's magnetic field with
tiny magnetic tissues in their head (magnetoception). This is
all the more surprising as they are not a migratory species, which is a fact
used by some ornithologists to dispute this theory. Another
theory is that pigeons have compass sense, which uses the position of the sun,
along with an internal clock, to work out direction. However, studies have
shown that if magnetic disruption or clock changes disrupt these senses, the
pigeon can still manage to get home. The variability in the effects of
manipulations to these sense of the pigeons indicates that there is more than
one cue on which navigation is based and that map sense appears to rely on a
comparison of available cues.
Other potential cues used include:
- The use of a sun compass
- Nocturnal navigate by stars
- Visual landmark map
- Navigation by infrasound map
- Polarised light compass
- Olfactory stimuli
Other purposes of pigeon breeding
For Food
Pigeons are also bred for meat, generally called squab and
harvested from young birds. Pigeons grow to a very large size in the nest
before they are fledged and able to fly, and in this stage of their development
(when they are called squabs) they are prized as food. For commercial meat
production a breed of large white pigeon, named "King pigeon," has
been developed by selective breeding. Breeds of pigeons developed for their
meat are collectively known as utility pigeons.
Exhibition breeds
Pigeon fanciers developed many exotic forms of pigeon. These
are generally classed as fancy pigeons. Fanciers compete against each other at
exhibitions or shows and the different forms or breeds are judged to a standard
to decide who has the best bird. Among those breeds are the English carrier
pigeons, a variety of pigeon with wattles and a unique, almost vertical, stance
(pictures). There are many ornamental breeds of pigeons, including the
"Duchess" breed, which has as a prominent characteristic feet that
are completely covered by a sort of fan of feathers. The fantail pigeons are
also very ornamental with their fan-shaped tail feathers
Flying/Sporting
Pigeons are also kept by enthusiasts for the enjoyment of
Flying/Sporting competitions. Breeds such as tipplers are flown in endurance
contests by their owners.
Experimentation
Domestic pigeons are also commonly used in laboratory
experiments in biology, medicine and cognitive science.
Cognitive science
Pigeons have been trained to distinguish between cubist and
impressionist paintings, for instance. In Project Sea Hunt, a US coast guard
search and rescue project in the 1970s/1980s, pigeons were shown to be more
effective than humans in spotting shipwreck victims at sea. Research in
pigeons is widespread, encompassing shape and texture perception, exemplar and
prototype memory, category-based and associative concepts, and many more
unlisted here (see pigeon intelligence).
Pigeons are able to acquire orthographic processing
skills, which form part of the ability to read, and basic numerical skills
equivalent to those shown in primates.
Illegal predator killing by enthusiasts
In the United States, some pigeon keepers illegally trap and
kill hawks and falcons to protect their pigeons. In American pigeon-related
organizations, some enthusiasts have openly shared their experiences of killing
hawks and falcons, although this is frowned upon by the majority of fanciers.
None of the major clubs condone this practice. It is estimated that almost
1,000 birds of prey have been killed in Oregon and Washington, and that
1,000–2,000 are killed in southern California annually. In June 2007, three
Oregon men were indicted with misdemeanour violations of the Migratory Bird
Treaty Act for killing birds of prey. Seven Californians and a Texan were also
charged in the case.
In the West Midlands region of the United Kingdom pigeon
fanciers have been blamed for a trap campaign to kill peregrine falcons. Eight
illegal spring-loaded traps were found close to peregrine nests and at least
one of the protected birds died. The steel traps are thought to have been set
as part of a "concerted campaign" to kill as many of the birds as
possible in the West Midlands
Feral pigeons
Many domestic birds have escaped or been released over the
years, and have given rise to the feral pigeon. These show a variety of
plumages, although some look very like pure rock pigeons. The scarcity of the
pure wild species is partly due to interbreeding with feral birds. Domestic
pigeons can often be distinguished from feral pigeons because they usually have
a metal or plastic band around one (sometimes both) legs which shows, by a
number on it, that they are registered to an owner.
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