Don't hate the successful just because they're beautiful Studies show appearance counts for a lot but basing decisions on looks may not be good business Whatever one might think of Margaret Thatcher, on one policy the late British prime minister turns out to have been dead right: taking those elocution lessons to lower her voice. At the time I was outraged that a woman who had just been elected to the highest office felt the need to sound like a man. But now I discover it had less to do with women-versus-men than with lowness per se: even among men it seems the lower the voice, the better. Scientists at Duke University have been studying the vocal ranges of 792 US chief executives and found that those with deeper voices tend to run larger companies, get paid more and last longer in the job. A drop of 22 Hertz in voice frequency implies a company $440m bigger, a pay packet $187,000 higher and an extra 151 days on the job. These sorts of weird statistics come from a fashionable new academic field called biological economics, which sets out to match physical traits with monetary reward. There have been a huge number of studies done in recent years and last week I slogged my way through a lot of them. The more I read the more disturbed I got at the conclusion they all point to: the tall, the powerful, the gorgeous and the low-voiced do rather well. The short, fat, feeble and squeaky-voiced do a great deal less so. The best known studies have been on height. A 2005 survey revealed that Fortune 500 CEOs were on average 6ft tall - a whopping 2.5 inches taller than the average American man. Most CEOs are painfully aware of this height advantage. When USA Today recently asked them if they would rather be two inches taller or have a full head of hair, almost all plumped for height. This seems to be the right answer. Being bald as a coot does not lessen a man's chances of success - it appears to increase them. Not only are there plenty of bald role models - Microsoft's Steve Ballmer, Daniel Akerson of GM - but according to a Wharton business school study, men with bald heads are perceived by others as more dominant. And that's not all: they are also perceived as taller and stronger than those whose heads are covered with a thick thatch of hair. Hair on the chin turns out to be another matter entirely. What this gets you is not power but trust. Men with beards were found in a study written up in the Journal of Marketing and Communications to be more trusted by consumers than the clean shaven, except when selling male underwear, in which case the beard was best avoided. In addition to analysing height and hair follicles, biological economists have also spent time poring over CEOs" faces. One study established a positive link between width of face and size of company. The broader the face, the better. Another got students to look at cropped CEO mugshots and assess them for signs of power and warmth. Again, those with faces deemed powerful headed the more successful companies. If powerful looks are a mighty advantage, so too is beauty. Various studies have shown the existence of a "beauty premium" - the gorgeous are estimated to earn 10-20 per cent more than the rest of us. There was a piece of work done at Harvard a few years ago in which job candidates solved maze puzzles. The beautiful were no better at the task than the plain but employers were considerably keener on hiring them. For women, what counts as beautiful has been refined further by the biological economists and unfortunately for us brunetters, it turns out to entail being blonde. A report from the University of Queensland came up with the distressing finding that the fair-haired earn on average 7 per cent more than everyone else. And as for the fat, they do particularly badly. There is a sad little equation emanating from New York University connecting pounds of flesh with pounds of money forgone. A 1 per cent increase in body mass apparently results in a 0.6 per cent fall in income. If this really is how the world works - and it's a bit hard to deny it given the research - there is an obvious answer for us. We must variously wear heels, dye our hair, go on a diet, employ Thatcher's voice coach, shave our heads and puff out our cheeks. Yet from an employer's point of view, there is a different lesson to be drawn from biological economics. The rational thing to do is to exploit the bias in the market. To let everyone else pay a premium for towering beauties and to employ only the short, the badly dressed and the squeaky-voiced. They will be as good at their jobs as the beauties. But they will be more loyal. And they'll be a good deal cheaper, too.