Mobile Phones Change Birds' Tune
Published on: 30th Jun 2008
Note -- this news article is more than a year old.
BERLIN, Jun 23 (Tierram rica). Many wild birds are able to imitate the simple ringtones of mobile telephones, German ornithologists report, underscoring the influence of humans on the evolution of birds.
These birds can "sing up to 78 different phrases, and many of the simplest phone ringtones coincide with them," ornithologist Matthias Werner, of the government's bird protection agency, told Tierram©rica. "The common titbird (Parus major) can sing 32 different songs," he said.
According to Werner, birds like the Euroasian jackdaw (Corvus monedula), the European starling (Sturnus vulgaris) and the Eurasian jay (Garrulus glandarius) -- very common in Germany and other Central European countries -- were put in contact with electronically created sounds as a result of the expansion of urban life, the food opportunities provided by cities, and the fast-paced growth of mobile phone use.
Another factor that attracts birds to cities is the expansion of protected green areas in urban perimeters.
Several other ornithologists have reached conclusions similar to Werner's.
"It's in the nature of these birds to imitate the sounds of their environment that correspond to their own musical capabilities," said Richard Schneider, of the NABU Bird Protection Center, in the city of M¶ssingen (600 km south of Berlin).
"They can imitate those sounds so well that sometimes it is very difficult to hear the difference," he told Tierram©rica.
"That's how evolution is: there is no predetermined scheme, and the influences of the environment, even if they are artificial, turn out to be considerable," he added.
"The song is useful for male birds not only in the search for a female or to mark its territory, but also as a deceptive maneuver when faced with potential dangers. For this reason, imitating environmental sounds is part of the daily lives of birds," explained Schneider.
The jay, which is particularly timid, is able to imitate the songs of other birds, sounds cries of alarm to warn of danger, or sounds like cracks or meows. The black starling simulates the sound of brakes, human whistles and even ambulance sirens.
The experts agree that these phenomena do not imply the loss of the species' original songs.
Nor is the apparent cacophony dangerous. The diversity of songs can only be identified by members of each species. Most wild birds are not yet able to repeat the more complex sounds made by the newer mobile phones, or the polyphonic sounds of electronic music.
This adaptation comes as no surprise to biologists or other experts in ecology. "No species can survive if it isn't capable of adapting," biologist Matthias Glaubrecht, professor at Humboldt University in Berlin, told Tierram©rica.
"The decisive factors are the scope and velocity of change in the environment of the species," said Glaubrecht, research director for the university's Museum of Natural History.
It is possible that species sometimes may be able to adapt to very rapid changes. "But in many cases it's evident that human activity is the accelerator to evolution," he said.
Given the risk that birds might forget their original song as a result of human influences, their songs have been archived in European and North American universities, allowing the possibility of recovering them -- a step backwards, perhaps, in the constant process of adaptation that is evolution.
The Museum of Natural History alone holds more than 110,000 recordings of sounds made by birds, mammals, insects and even fish. The archives include the songs of 1,800 bird species.
Those files are part of a European network of biological acoustics for taxonomy and conservation, created in 2006 to manage the recordings of animal sounds as a research tool.
Because climate change poses a serious threat of extinction for many species, collecting animal sounds is considered a crucial tool for environmental protection. Bio-acoustic signals are specific to each species and these behaviors are lost forever when a species goes extinct.
The European network for bio-acoustics states in its founding charter that it is urgent to facilitate knowledge, preservation and precise documentation of acoustic signals in the animal kingdom.
According to the sound archive director at Humboldt University, Karl-Heinz Frommolt, animal taxonomy should be accompanied by a non-invasive study of the habitat by the researcher, and "the acoustic method is very useful for determining measures of environmental protection to be adopted."
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