A study published in Royal Society Open Science supports the notion that singing together is a good way to make friends.
Researchers compared the bonds forged when participants joined a range of adult education classes: singing, creative crafts or creative writing. Results showed that the singers got to know each other much more quickly than the artists or writers.
The social scientists among you might wish to follow the above link to read the full report; for a less academic reflection, Yahoo Finance is the place to go.
Now, I wonder who has studied the bonds between sopranos and altos, or tenors and basses? That would be interesting……..