Yes, the Mosuo are one example. They are also known as the Na. Read the "Walking Marriages" section of that Wiki page that Opalescent linked to. Very interesting people. There is a book called A Society without Fathers or Husbands: The Na of China
. From a book review in the publication American Ethnologist
The Na have shocked Han Chinese ethnologists
by not having marriage; rather, they practice
"visiting relations" -- consensual sexual relations
in which both partners remain members
of their natal households and never form an
economic or social union recognizable as
marriage. Na men visit their partners in the
evening and return home by morning to mothers,
aunts, uncles, and siblings, to join in their
own household's work. Either partner can end
a relationship at any time, and both can take
other lovers during or between longer-term
In Na matrilineal households, the father is
considered socially unimportant, and, prior to
the Na's inclusion in the communist state, his
identity was often unknown.
The Na share an understanding, albeit flexible,
of the family as the blood or adopted members
of the household; they see the family as central
to their emotional, economic, and social existence
. . . it is because the Na believe that families should
be stable and harmonious that they do not base
family structure on romantic relationships. These
Na say that love for family members is enduring,
whereas passion is fleeting.
Just makes one think a bit about what's important. The Na's system enables a separation between familial love and sexual love/passion, which frees the adults to take on as many lovers as they wish without recrimination.
The Na live communally and the men don't rule the households nor have any ownership over the women or their offspring. Paternity is not integral for the community to thrive and function well, nor for any of the children to be loved, cherished, and raised well. The women who have children raise them with the help of their siblings, and family is preserved that way. The women's brothers (uncles to their sisters' children) help raise them. Men with only brothers probably share in raising children of other related households, or work to support the larger village. Men's contributions to their society are important, but it doesn't matter which children are theirs and there is not an emphasis on preferring male children to be born.
I think it's a great model for communal living but it would be a very brave endeavor in modern Western societies, where paternity is usually considered of utmost importance (a belief that was useful when woman and children were considered property). Yes, there maybe medical reasons for knowing paternity, but the Na live in a way that shows how possible it is to have a functioning society in which having sexual liaisons purely for pleasure and outside a bond like marriage is not something shameful! They also teach us how unimportant socially and culturally it can be to know whose seed the children come from. Loving and raising a child shouldn't be limited to biological offspring only, IMO.