雅思听力

🎧 Listening Transcript

Today, in our series on urban wildlife, we're looking at the impact of city life on bird populations. Recent studies in London and New York have shown that birds in urban areas have adapted their songs to be higher in pitch, which helps them be heard above the low-frequency noise of traffic. However, this adaptation has a downside: the higher-pitched songs are less effective at attracting mates in quieter, suburban areas. Interestingly, researchers also found that urban birds tend to start singing earlier in the morning, possibly to take advantage of quieter periods before rush hour. This shift in behavior, while beneficial for communication, may affect their breeding success in the long term.