So it shouldn't be surprising to learn parents have the same bias. Still, the headline in Science Times was jolting: "Ugly children may get parental short shrift." As Nicholas Bakalar wrote: "Canadian researchers have made a startling assertion: parents take better care of pretty children than they do ugly ones."

Researchers at the University of Alberta observed that at the supermarket, less adorable tykes were more often allowed to engage in potentially dangerous activities - like standing up in the shopping cart or wandering off. Good-looking children, especially boys, got more attention from their parents and were kept closer at hand. "When it came to buckling up, pretty and ugly children were treated in starkly different ways, with seatbelt use increasing in direct proportion to attractiveness," the article said. "When a woman was in charge, 4 per cent of the homeliest children were strapped in, compared with 13.3 per cent of the most attractive children." With fathers, it was even worse, "with none of the least attractive children secured with seatbelts, while 12.5 per cent of the prettiest children were". Haven't these parents heard of the ugly duckling? Do they read to pretty kids only about pretty ducklings?

Even if you're sceptical about supermarket science, the story conjures up poignant images of ugly rugrats toddling off, or flying through the air and crashing into the rotisserie chicken oven because they're not belted in. Dr Andrew Harrel, the research team's leader, put the findings in evolutionary terms: pretty children represent a premium genetic legacy, so get top care.

"Like lots of animals," he said, "we tend to parcel out our resources on the basis of value." As Marilyn Monroe explained in Gentlemen Prefer Blondes: "Don't you know that a man being rich is like a girl being pretty? You wouldn't marry a girl just because she's pretty, but my goodness, doesn't it help?" A beauty bias against children seems so startling because you grow up thinking parents are the only ones who will give you unconditional love, not measure it out in coffee spoons based on your genetic luck - which, after all, they're responsible for.

But the world can be harsh. Surface matters more and more, and the world ignores Shakespeare's lesson from The Merchant of Venice: "Gilded tombs do worms infold." An analysis published last month by the Federal Reserve Bank of St Louis suggests that the good-looking get more money and promotions than average-looking schmos.

Quoting economists Daniel Hamermesh and Jeff Biddle, the study notes that being tall, slender and attractive could be worth a "beauty premium" - an extra 5 per cent an hour - while there is a "plainness penalty" of 9 per cent in wages (after excluding other issues). Researchers report that taller men are more likely to win in business and - except for the hapless Al Gore and John Kerry - get elected president. Correlating 16-year-olds' height with their later salaries shows beanstalks grow up to earn about $US789 more a year for each extra inch (2.5 centimetres) of height. In his best-seller Blink, Malcolm Gladwell did a survey of half the Fortune 500 CEOs, and found that the average CEO, at 1.8 metres, was about 7.6 centimetres taller than the average American man.

As Randy Newman sang, "Short people got no reason to live." Research also shows that obese women get 17 per cent lower wages than women of average weight and that dishy professors get better evaluations from their students.

There can be too much of a good thing. As Dan Ondrack, a professor at the University of Toronto, told The Toronto Star, there's a "Boopsey" effect - if women are too gorgeous, people assume they are airheads. No one seems sure whether bosses discriminate against people because they're less attractive, or whether more attractive people develop more self-esteem and social finesse. But one thing's for sure. It's hard to develop self-esteem when you're hurtling out of the supermarket cart towards the rotisserie oven.