In the same way that wild animals do not 'organise' orgies, but sex with multiple partners at one time takes place quite frequently, I imagine that group sex has been around for as long as human beings have.

If sex has evolved, I would argue that it has become more 'civilised' and tabboo than in previous times, certainly when you look at ancient Greek and Roman cultures and no doubt going further back in history than that. I think it is naive to assume that our sexual practises today are 'wilder' than they were thousands of years ago, as I'm pretty sure that group sex, incest, rape and underage sex are far less common practises today than once they were.

The sophistication of our pornography may well have evolved however, I think this, at least in part, has developed as more and more sexual practises have become frowned upon in the 'real world' and become the stuff of fantasy only.

Sex in art, drama and literature has definitely become more tame than in previous times. A particular phrase from a Greek comedy we studied in school will remain in my head for eternity:

"He cunnilingus practises,
On all the whores in town"

Considering this was part of a popular play (the equivalent form of entertainment as watching TV or going to the cinema) it's a pretty risque line by today's standards, but was considered funny but not shocking back then. Likewise in Greek comedy, male characters not only wore masks but also cod pieces with a massively exagerated false erection attached to them, purely for comedy value. Again, I can't even see this going down well in the bawdy comedies of Shakespeare or Chaucer's generation.

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