Iain Murray: Raven-haired birds are no good for nesting with

The workaday life of every professional is afflicted by longueurs, those episodic bouts of boredom into which doubts creep and a tiny voice asks, “Is it all worthwhile?”

I imagine it was during one of these black spells that Professor Hans Juergens of Kiel came up with his idea. He is an anthropologist and therefore more given than most to dark rumination. When it is one’s lot to sit – or sometimes to stand and wander from corner to corner scratching one’s head – in Kiel, contemplating man as an animal, the alternatives, such as slitting one’s throat, must seem beguiling.

And so it was that Prof Juergens cast aside his duty to anatomise the hairy hunter-gatherer, the bequeather of mystifying fragments of his own skeleton, and distractedly took up his pen. What he did next may have surprised his colleagues; come to that, it may well have surprised him. What Prof Juergens did was to write two advertisements for the small ads columns of the local paper; both purported to be from a 26-year-old woman looking for a husband, but one was a blonde, the other a brunette.

My source for this information – a newspaper cutting – is regrettably scant, so I do not know the precise details of his methodology, only his findings, which are as follows: “The men were interested in an affair with the dark-haired woman, but were thinking of sharing their lives with the blonde. And the blonde only got a third as many letters as the brunette.”

Pity about the gap in our knowledge of the methodology – it leaves many questions unanswered. Are German male respondents to lonely hearts columns uncommonly frank about their intentions? Did those writing to the brunette, whom they had not set eyes on let alone met, tell her in so many words to forget about marriage but to accept by way of compensation that which Britishers call a “romp”?

Or did the professor take his experiment further? Did he perhaps engage the services of a female assistant who, equipped with the relevant wigs, played the parts of the lonely hearts and discovered the true intentions of the would-be suitors? Did his budget run to two assistants, one for each colour? Or – an intriguing possibility – did he slip into something more comfortable and assume the roles himself? In which case he has unwittingly opened a new field of research into chronic myopia among lovesick German males.

However, putting the mystery of his methods to one side, Prof Juergens considered his findings worthy of publication. He claims, as we have seen, that men prefer blondes for marriage but choose brunettes for passion. Sensing perhaps that, though interesting in its way, his thesis is – how should one put it? – inconsequential, he adds that these male preferences are already exploited by advertisers.

Well wouldn’t you know it? It’s those hidden persuaders again, deftly pulling on the strings of our emotions without us feeling a thing – consciously, that is.

Blondes, says the Juergens, promote cleaning products, while brunettes feature in ads for chocolate, alcohol or lingerie. That neatly ties in with the preferences of the German males – blondes for domesticity, brunettes for the things that make life exciting.

As luck would have it a new book, Celebrity Sell – Star Endorsements in the Classic Age of Advertising (Prion, £7.99) allows us to test his hypothesis. And would you believe it, he’s right. The most famous blonde of all, Marilyn Monroe, promoted Lustre-Crème – a beauty shampoo which, though not a cleaning product in the Sanilav sense, is nevertheless at least one stage removed from the sensual. While Marilyn was washing her hair, the young Elizabeth Taylor, one of Hollywood’s most ravishing brunettes, was enjoying Whitman’s chocolates – a bullseye for the professor. Julie Andrews, looking very blonde, extolled Vitapointe – “Give your hair shining, flashing beauty” – while Rita Hayworth, a redhead (which must surely put her at the brunette end of the spectrum, if not beyond in a superheated class of her own), “danced 36 miles in wispy Mojud ’Magic Motion’ Stockings”.

So where does this leave us? Academic work, of course, need have no practical application – the pursuit of knowledge is sufficient unto itself. Nevertheless it would be nice to think that when the professor’s thoughts revert once more to metalworking techniques in Mesopotamia in 3500BC, he will have left behind something of lasting use.

Since there is not much about in the way of celebrity advertising at the minute, perhaps use could be made of Professor Juergens’ research by applying its findings to the fields of news and weather broadcasting, nowadays almost entirely the province of women, and increasingly preoccupied by appearance rather than content. Let us, then, have two-girl teams of presenters – one blonde, one brunette. The blondes could bring us good news of apple-cheeked children rescued from blazes, and of the Queen Mother bravely riding her golf-cart; the brunettes could relate exciting tales of corruption in high places, of sex ’n’ drugs, chocolates and whisky, and Magic Motion stockings. The blondes would forecast sunny days with light breezes, perfect for hanging out the washing; the brunettes would tell of lowering, Heathcliffian skies, chill winds, and driving rain, and hint coyly at fireside rugs.