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communication as can humans. Nevertheless, the evidence is clear that noise has negative effects on avian communities, including detection of prey and predators and intraspecies communication. To be fair, there are occasional exceptions to this rule as in the case where noise may interfere with avian predators, making it more difficult for them to prey on birds (Francis et al., 2009).
Communicating in Noise: Bird Communication May be Even More at Risk
We think of speech perception and vocal communication as hearing the structure of individual words and the sequences of words that convey emotion and meaning. As far back as
Aristotle (reprinted in 1984), birdsong has fascinated casual observers and, more recently, professional researchers for its similarities to human speech. Over the years, the complex and melodic nature of many species’ songs has especially raised interest in the potential parallels between avian vocal sequences and human linguistic patterns.
Recent research aimed at this question has discovered some- thing that is somewhat unexpected. Although birdsong is sequentially complex, birds, in contrast to humans, actually pay less attention to the sequences of elements in their song and much more to the fine acoustic details of each individual element or syllable (Lawson et al., 2018). We now know that birds hear birdsong much differently than humans, focusing on the fine details of each individual element with a much greater resolution than humans (Dooling and Prior, 2017; Prior et al., 2018). This is a level of communication using fine acoustic detail that is beyond human hearing. Thus, it is possible that increases in ambient-noise levels from anthropogenic noises, such as traffic, may have an even more deleterious effect on acoustic communication between birds than we can imagine based on what we know about how noise affects speech com- munication in humans.
Acknowledgments
This paper is derived and updated from a report that was funded by the California Department of Transportation. Marjorie R. Leek is supported by VA Senior Research Career Scientist Award C4042L from the VA Rehabilitation Research and Development Service.
Any statements expressed in this paper are those of the indi- vidual authors and do not necessarily represent the views of the California Department of Transportation, the US Department of Veterans Affairs, or the US Government.
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