City life causes song birds to change their tune
City life causes song birds to change their tune
mongabay.com
December 4, 2006
Cities cause birds to change their songs according to research published in the December 5th issue of the journal Current Biology.
Hans Slabbekoorn and Ardie den Boer-Visser, biologists from Leiden University in the Netherlands, studied songs of the great tit (Parus major), a species that has successfully adapted to urban life, in ten major European cities, and compared them to songs of great tits living in nearby forest areas. They found that urban songs were shorter and faster-paced than the forest songs, and tended to be higher frequency to overcome the low-frequency environmental noise, such as traffic noise, associated with cities.
The researchers say the findings show that “songs undergo a habitat-dependent acoustic shift in cities that is driven by traffic noise” and lend support to the acoustic-adaptation hypothesis, which argues that “some aspects of the vocal variety of animal communication sounds are shaped by the environment.” Slabbekoorn and den Boer-Visser note that the results suggest that “song divergence within a species as a result of such “environmental shaping” could potentially play a crucial role in the process of speciation, although it is not at all clear whether urban and forest populations of great tits are on such a path.” according to a news release from Cell Press, publisher of Current Biology.
Great Tit Song Variation in Urban and Forest Sites. Image courtesy of Current Biology. |
According to the researchers, it appears that song-type selection are divergent between city birds and forest birds. In other words, city birds are singing entirely different songs than forest birds findings which have implications for species conservation.
“Most insight would be gained by data on song-learning abilities and … experimental data on the impact of noise interference on signal efficiency, reproductive output, and fitness,” write the authors. “Insight into these features across species will allow predictions about species-specific sensitivities to traffic noise in cities as well as along highways. Such knowledge may become critical for conservation efforts that aim to prevent a division between those species that can make themselves heard and those whose songs drown in the urban rumble.”
Citation: Slabbekoorn et al.: “Cities Change the Songs of Birds.” Publishing in Current Biology 16, 2326—2331, December 5, 2006 DOI 10.1016/j.cub.2006.10.008
This article is based on a news release from Cell Press.