A researcher claims to have set a new record for the oldest known parrot fossil, and at the same time helped to rewrite natural history.

The 55 million-year-old bone was dug from a Danish quarry and proves the birds lived on the edges of the North Sea - much further from the tropics than previously thought.

It is officially known as Mopsitta tanta, but Dr David Waterhouse has nicknamed it the Danish Blue after the popular Monty Python comedy sketch featuring a dead Norwegian parrot.

The remarkable find, published yesterday in the journal Palaeontology, was uncovered after Dr Waterhouse was asked to inspect a 5cm to 6cm bone which had lain unidentified in a Danish museum for several years.

"Obviously, we are dealing with a bird that is bereft of life', but the tricky bit is establishing that it was a parrot," he said.

The fossil was found on a quarry on the Isle of Mors in Denmark eight years ago and is believed to be the oldest, largest and most northerly discovery of parrot remains.

Dr Waterhouse said the bone is a single, upper-wing bone - named the humerus - and the bird would have been roughly the size of a crow.

"As with many fragile bird fossils, all that remains of this early Danish parrot is a single upper-wing bone," Dr Waterhouse said.

"It isn't as unbelievable as you might at first think that a parrot was found so far north," he said.

"This was only 10 million years after the dinosaurs were wiped out.

"Some strange things were happening with animal life all over the planet."