Songbirds include those birds from the order Passeriformes, commonly called passerines. There are approximately 5,400 different species of passerines. The suborder Oscine includes those birds that we tend to think of as your typical songbird, those birds that have complex songs as adults. In the majority of Oscines, the male is the one with the complex singing ability, and there is much diversity among males of different species in the length and complexity of their songs.
Song needs to be developed, just like any other characteristic of songbird behavior. Singing the correct song for that species is not an instinctual process. The need to sing is instinctual, however what song to sing has been found to be learned. When and where young songbirds learn their songs has long been studied. Just as songbirds differ in their songs, they also differ in their song learning process, though some basic principles seem to be the same. Many species learn their song only during the first few months, though a few can learn songs their entire lives. Also differing between species is from who the songs are learned, and how much of the songs are accurately imitated.
Some species may exactly copy the songs they are exposed to. On the other hand, many will not exactly imitate the song or songs that they have been exposed to. Instead they will take bits and pieces of it and invent their own song, though usually similar in construction to that which the species normally sings.
bits and pieces：曲子的部分调子或小节