In the forthcoming edition of the American Sociological Review, Elizabeth McClintock reports her research that appraised a representative sample of more than 1,500 young married couples and found minimal evidence of couples "trading" a woman's looks against a man's wealth or status.

Instead, McClintock found that the overwhelming majority of couples marry by similarity, so more successful men marry more successful women and, unsurprisingly, better-looking people tend to marry each other.

While this might fly in the face of received wisdom, the professor points out that there are large observational biases at play. Tabloid newspapers love reporting celebrity gossip involving rich old men marrying younger women, and on a day-to-day basis we tend to notice examples of phenomena that match our stereotypes, while ignoring all contrary instances. Since we carry our gender stereotypes into these judgments, we tend to assume that a good-looking, intelligent, successful man has attracted his good-looking, intelligent, successful wife through his success, while she has attracted her husband through her looks. Both assumptions are likely to be (at least partially) wrong.

Admittedly there is one small complicating factor. Attractiveness does not sit easily on a metric. Wealthy, successful people have access to better health, fitness and beauty regimes, and to more attractive clothes and accessories, and tend to exude confidence and self-belief which are in themselves attractive traits. To confound things further, there is a lot of evidence in social psychology literature that not only are successful people perceived as being more attractive, but more attractive people tend to be perceived as more successful, and actually are more successful in their careers.

The study is the latest contribution to the social science field which shows how growing gender equality in educational, economic and professional realms is profoundly changing our romantic and sexual habits. In recent years the growing trend towards what is romantically dubbed "assortative mating" (forming relationships with those like ourselves) has been identified as a significant factor in restricting social mobility in the developed world.

Whereas once doctors would typically marry nurses and bosses would marry secretaries, now doctors tend to marry other doctors, and bosses other bosses. With younger women now out-performing young men in both education and earnings, this should surprise no one. This year Pew Research found that the share of US couples in which the wife is the one "marrying down" (at least on an educational basis) is, for the first time, now higher than those in which the husband does the same. The pattern is still not quite the same for earnings. Only 39% of the more educated wives were also the higher earning partner, but that gap too is closing by the year.

There is something very gratifying in being able to throw out these dated assumptions about men, women and their marital habits. The assumption that men are irresistibly drawn to a bulging bosom while women are similarly drawn to a bulging wallet is one of those stereotypes that manages to be grossly demeaning to men and women alike.

Yes, for centuries women tended to pair off with men of similar background and interests but considerably larger incomes. That was not because women are natural born gold-diggers, but because historically a man would be almost invariably earning a higher income or have greater independent wealth than a woman of similar background and interests.

Similarly, one would need a pretty dim view of men to imagine that a pretty face or shapely body could turn our heads for an evening, but that we would be prepared to share our lives with a woman who means no more to us than an accessory on our wrist.