Faith strongly influences people's attitudes to morality and whether or not they view monogamy as natural for humans

The recent Supreme Court decision which asserted that the right to marry is a constitutional right, including for same sex couples, has raised prompted some commentators to question whether the same could be said of polygamy. Polygamy has long been prohibited and rarely practised in the United States, but at least the practise is quite common in many parts of the Islamic world and sub-Saharan Africa. What is increasingly common in the United States, however, are various forms of 'polyamory', where people have multiple sexual and romantic partners with the full knowledge of their partners.

YouGov's research shows that most Americans (56%) reject the idea that polyamory is somehow morally acceptable, though one quarter of the country does think that polyamorous relationships are morally acceptable. Polygamy, that is marriage between more than two people, is even less acceptable, with 69% saying that polygamy is immoral and only 14% believing that it is morally acceptable.

Attitudes towards polyamory depend significantly on how religious someone is. 80% of people who say that religion is 'very important' in their lives say that polyamory is wrong, but among people for whom religion is 'not at all important' 58% say that polyamory is morally acceptable.

Most of the country believes that polyamory is immoral, but the country is more divided when it comes to whether or not human beings are monogamous by nature. 42% of Americans believe that humans are naturally monogamous, but 35% believe that they are not.

There is a gender divide on this issue, as men are much more evenly divided than women are. 42% of men say that human beings are not naturally monogamous, compared to 40% who say that they are. Among women, however, 44% believe the human nature is to be monogamous compared to only 29% who believe that we are not naturally inclined to be faithful.

In Britain the gender divide is even more pronounced, with men saying humans are not naturally monogamous 46% to 36%, and women saying that humans are 46% to 32%.

Overall, Americans are slightly more likely to say that women (73%) can successfully manage monogamous relationships than men (64%).

Full poll results can be found here and topline results and margin of error here.