What is a good car alarm?

At what stage of life can a mockingbird properly learn and replicate the common six tone car alarm, and why would it choose to chirp and sing this as a birdsong?

• There is a mockingbird outside my window that has been chirping  and repeating the standard, very common six-tone car alarm, in the correct order, with stunningly accurate pitch, rhythm, and tone. This has been going on for at least the past half-hour. [1:00am-->onwards] I am wondering at what stage of this bird's life it most likely learned how to imitate this car alarm -- if it this occurs as a chick, or as an adult mockingbird. What is the process by which mockingbirds learn and repeat songs/tones, and why is it that the bird is choosing to sing this song in the wee hours of the morning? Why is the mockingbird choosing to chirp and sing this normally-annoying car alarm? Forgive me if this is a stupid question as I know very little about how mockingbirds imitate and repeat learned sounds. Feel free to answer any part of the question you know the answer to/all of it if you please. I am fascinated and want to learn. For reference, this is the car alarm I am talking about:

• Answer:

  I'm not sure if there's any particular stage of life where a mockingbird would be more apt to learn a car alarm as one of its songs, but I can tell you that a bird would not know the difference between a car alarm and any other sound in its environment. They mimic other birds, frogs, and even cats meowing or dogs barking. In some instances they do learn car alarms and cellphone ringtones. It's just a way of advertising that they've been around a while and know lots of different songs.