Brightly-coloured birds are likely to be less impressed by their own plumage than human nature lovers, research suggests.

Scientists know that a bird’s eye view is much more colourful than that of a human.

But although birds are sensitive to a wide range of ultraviolet hues invisible to humans, these are lacking from their plumage.

So bird colours that dazzle humans may seem drab to the birds themselves.

“Birds are among the most colourful organisms on the planet,” said zoologist Mary Caswell Stoddard, from Cambridge University. “To our human eyes, birds seem to possess almost every colour imaginable - but birds see the world very differently than we do.”

The research was published today in the journal Behavioural Ecology.

Working with colleagues in the US, the Cambridge scientists studied the full range, or “gamut”, of plumage pigments and matched them against what colours birds can see. They found vast regions of available “colour space” visible to birds missing from their plumage. Birds were able to make only about 26 per cent to 30 per cent of the colours they were capable of seeing.

“Just as a newspaper can only print a fraction of the colours we humans can see, bird feathers can only produce a subset of colours that are theoretically visible to other birds,” Ms Stoddard said. “The intriguing part is thinking about why plumage colours are confined to this subset. Out-of-gamut colours may be impossible to make with available mechanisms, or they may be disadvantageous.

“That doesn’t mean that birds’ colour palette might not eventually evolve to expand into new colours.”

Co-author Richard Prum, from Yale University in the US, said: “Evolutionary innovations in the form of new pigments and structural colours enabled birds to colonise new areas of avian colour space.

“In the same way, human clothing was pretty drab before the invention of aniline dyes like mauve, but chemical inventions allowed clothing to become more diverse in colour. Our study documents the history of mechanistic constraints on bird colour diversity.”