As it happens this weekend I was listening to a CD of field recordings of Chinese boatmen's and logger's work songs that I have. ("Songs of the Land in China: Labor Songs & Love Songs.") Most of the liner notes are in Chinese so I can't read them, but sea chantey enthusiasts may find this description sort of familiar:

"These songs are usually sung together by every member of a team or working group. One member takes the role as lead vocal; this role, in face, is actually more complex than just being the lead. It includes the task of creating new lyrics for a set melody, and most importantly, commanding the whole group to be more productive."

According to the CD notes, the Chinese word for these kinds of songs is "haozi" or "shaozi" which is also the word for a type of whistle. Perhaps useful info for those looking for more info on these songs?

The videos are very interesting, I wasn't sure what kind of work went along with these sort of songs.