|Homing pigeon (Columba livia domestica) portrait. (© LightColourShade. All rights reserved)|
9 February 2015
Homing pigeon (Columba livia domestica), Common Blackbird (Turdus merula), Eurasian Common Moorhen (Gallinula chloropus), Common Wood Pigeon (Columba palumbus), Common Pochard (Aythya ferina), and Great Cormorant (Phalacrocorax carbo)
Homing pigeon is a variety of domestic pigeon (Columba livia domestica) derived from the rock pigeon, selectively bred to find its way home over extremely long distances (up to 1,800 km). The wild rock pigeon has an innate homing ability, meaning that it will generally return to its nest and mate. Their average flying speed over moderate distances is around 80 km/h (50 miles per hour) but speeds of up to 140 km/h (90 miles per hour) have been observed in top racers for short distances. Homing pigeons are called messenger or carrier pigeons when they are used to carry messages. Pigeons can find their way back from distant places they have never visited before. Most researchers believe that homing ability is based on a "map and compass" model, with the compass feature allowing birds to orient and the map feature allowing birds to determine their location relative to a goal site (home loft). While the compass mechanism appears to rely on the sun, some researchers believe that the map mechanism relies on the ability of birds to detect the Earth's magnetic field. Scientists discovered on top of pigeon's beak large number of particles of iron which remain aligned to north like manmade compass, thus it acts as compass which helps pigeon in determining its home, and it looks like the trigeminal nerve plays a role in magnetoception, too. Some studies showed that pigeons also orient themselves using the spatial distribution of atmospheric odours, known as olfactory navigation, as well as low frequency infrasound. In areas they have previously visited, pigeons are probably guided by visual landmarks, such as roads and other man-made features, just like humans. However, various experiments suggest that different breeds of homing pigeons rely on different cues to different extents.