Family Values: Natural's Not In It

'Throughout history and in virtually all human societies marriage has always been the union of a man and a woman." So says the Coalition for Marriage, whose petition against same-sex unions in the UK has so far attracted 500,000 signatures. It's a familiar claim, and it is wrong. Dozens of societies, across many centuries, have recognised same-sex marriage. In a few cases, before the 14th century, it was even celebrated in church.
This is an example of a widespread phenomenon: myth-making by cultural conservatives about past relationships. Scarcely challenged, family values campaigners have been able to construct a history that is almost entirely false...

A handy breakdown of the historical arguments that the family has always been in a state of flux by George Monbiot in The Guardian.
There's a very interesting Radio 4 programme here on Declinism - the belief that something or everything is not as good as it used to be.