听力音频：
L1
讲座
1. What is the discussion mainly about?
How birds use song to defend their territory
Effects of varying amounts of sunlight on bird behavior
Ways that birds adapt their songs to urban environments
Conservation efforts to protect wildlife near airports
2. What characteristic of birdsong was analyzed in the study about airport noise?
The volume of the singing
The timing of the singing
The variety of songs
The complexity of the songs
3. After observing bird behavior near an airport in Spain, researchers repeated their observations at several other locations. What properties of the locations caused researchers to choose them for the study?（多选题）
Sunrise occurred at various times in the locations
The locations consisted of both urban and rural environments.
The locations were not disturbed by artificial light in the morning.
The locations were home to many different predators.
4. What point does the professor raise about the singing behavior of birds near airports?
It is not very different from singing behavior in densely populated forests.
The singing is usually at a higher pitch than singing in areas not affected by urbanization.
It is difficult to study the behavior.
It is not known whether the behavior is inherited or learned.
5. What did researchers predict birds would do in echoing urban areas?
Increase the length of their songs
Sing from the top of tall buildings
Sing at a lower pitch than usual
Migrate to rural areas
6. Why does the professor mention a break in heavy traffic?
To describe a strategy that birds might use to adapt to noise.
To explain how birds migrate safely in urban areas.
To point out a problem with the design of an experiment.
To explain how researchers record birdsong in urban areas.
