One's christmas speech is now the same as one and all.

With each passing annus horribilis, Queen Elizabeth II sounds more like some of her trend-setting younger UK subjectswhen delivering her Christmas speech to the Commonwealth, new research reveals.

Jonathan Harrington of Macquarie University, Sydney, and his colleagues have analysed the vowel sounds from every Christmas broadcast made by Elizabeth II from the 1950s through to the 1980s. "There has been a drift in the Queen's accent towards one that is characteristic of speakers who are younger and/or lower in the social hierarchy," they now report in Nature 1.

The trend is towards the standard southern-British (SSB) accent, exemplified by BBC broadcasters, but subtly influenced by the London cockney accent imitated so poorly by Dick van Dyke in Mary Poppins.

Decades ago, the Queen would spend Christmas at h_ai_me with her family, with the first vowel sounding similar to that in the word 'tame'. Now they are more at home with everyone else, although not quite. "The vowels of the 1980s Christmas messages are still set apart from those of an SSB accent," Harrington's team says.

Peter Roach, who studies pronunciation at Reading University in England, and who edited a recent update of Daniel Jones' classic English Pronouncing Dictionary (Cambridge University Press) agrees that the Queen's accent is drifting. But, clearly not desperate for a knighthood, he suggests that she may have weighed anchor on purpose.

"Everybody's pronunciation changes over time but I'm sure that there is more to this than natural progression," he says. "I think it is a sign of a deliberate policy by the royals to become less of a target. If your accent was constantly pilloried and satirized then you would change it pretty quickly as well."

"I don't think that is something we could comment on," said a spokesperson for Buckingham Palace.

Roach continues: "Take the saying of the word 'one' by the royal family where most people would use 'I'. They dropped that pretty quickly once the media got hold of the idea and began mimicking it."

But other linguists dismiss this idea. "There is no evidence that there is any deliberate manipulation of pronunciation happening," says Gerry Docherty, who studies changing accents at the University of Newcastle-upon-Tyne's Department of Speech. But he suggests that the shift may reflect a change in the Queen's strategy for addressing a television camera. "Pronunciation often changes with people's perception of their environment," he says.

The research will no doubt dismay those who cling to the 'Queen's English' as the 'correct' way to speak. "[But] the chances of societies and academies successfully preserving a particular form of pronunciation against the influence of community and social change are as unlikely as King Canute's attempts to defeat the tides," the researchers say.

Roach agrees. "If you want to hear the future of the royal family's accent then just listen to Prince William," he says. "He was interviewed recently and I don't think there was anything in his accent that marked him out as royal or even as upper class."