Can birds outsing traffic? Some are trying

New research from scientists at the Centre for Ecological Research in Hungary finds that some birds living in cities are changing their songs to compete with traffic and other urban noise. ADRIAN FLORIDO, HOST: Take a listen to this robin. (SOUNDBITE OF ROBIN TWEETING) FLORIDO: Does it sound a little weird to you? (SOUNDBITE OF ROBIN TWEETING) FLORIDO: No? Well, what about compared to this robin? (SOUNDBITE OF ROBIN TWEETING) FLORIDO: These are two different robins - the first in a city, the second out in nature. New research shows that some city birds are actually changing their songs. MONIKA JABLONSZKY: Animals have to adapt to be able to live in cities. FLORIDO: This is Monika Jablonszky from the Centre for Ecological Research in Hungary. JABLONSZKY: It always starts with the simple sax and that (imitating rhythm). FLORIDO: She's been studying how and why these city dwellers are changing their songs. JABLONSZKY: The traffic noise is the most common. Not only the noise, but other urban phenomenon also influence songs, like the different physical structure of the environment because of the buildings. FLORIDO: Birds sing as part of the mating process or to mark territory. But what good does it do if your fellow avians can't hear you over the ruckus of the city? JABLONSZKY: So the birds try to sing higher. FLORIDO: They try to sing higher. Some birds change the frequency of their songs, others change individual notes. …