Queen's English has descended to level of the common people Royal pronunciation, perfect in the fifties, now sounds like that of a newsreader, say experts

It is not quite Eliza Doolittle in reverse, but tests on 11 different vowel sounds showed a tendency towards modern received pronunciation.

This is known as standard southern-British (SSB), as exemplified by BBC female broadcasters of the 1980s, with whom the scientists made their comparisons.

The researchers, from Macquarie University in Sydney, conducted an acoustic analysis of the vowels from the Queen's Christmas message from every year since 1952.

With the permission of Buckingham Palace, they compared the vowel sounds from the 1950s with those from the 1980s, and compared both with recordings by BBC broadcasters such as Angela Rippon.

Their analysis, published in this week's edition of Nature magazine, show the Queen's pronunciation of some vowels has been influenced by SSB, which is more typically associated with speakers who are younger and lower in the social hierarchy.

''Although modern received pronunciation has resisted many of the stigmatised features of the London cockney accent, such as aitch dropping, it has nevertheless been influenced by cockney - for example in the tendency to pronounce the 'l' in milk as a vowel,'' said Professor Jonathan Harrington, who led the research.

He pointed out that the standard British accent, or received pronunciation, has undergone many changes over the years, some of which have paralleled the changing attitudes towards social class.

There was marked social stratification in Britain in the 1950s. Even in the 1960s, when class barriers were starting to weaken, David Abercrombie, the phonetician, wrote: ''One either speaks received pronunciation or one does not, and if the opportunity to learn it in youth has not arisen, it is almost impossible to learn it in later life.''

But as class distinctions have become blurred, so too have the boundaries between English accents that mark social class, said Professor Harrington. This has been a trend led by younger people, who rejected received pronunciation because of its association with the establishment.

The older generation resented this, but were they impervious to it, or did they unwittingly adapt their accent towards community changes, he wondered. In fact, as he demonstrated, they have rubbed off on no less a person than the Queen.

''Thus, 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,'' said Professor Harrington.

''We conclude that the Queen no longer speaks the Queen's English of the 1950s, although the vowels of the 1980s Christmas message are clearly set apart from those of an SSB accent.''

The extent of such community influences was probably more marked for most adult speakers, who were not in the position of having to defend a particular form of English - in this case, the Queen's English.

He added: ''The chances of societies and academies successfully preserving a particular form of pronunciation against the influence of community and social changes are as unlikely as King Canute's attempts to defeat the tides.''