Birds of paradise have enthralled us for centuries but new discoveries are still being made about why these birds are one of nature's most stunning spectacles

The beautiful colours and elaborate displays of the birds of paradise have seen them held in the highest esteem by explorers, scientists and even royalty.

Family members have evolved strikingly varied plumages and in most cases males are also highly distinguished from females.

But this doesn’t mean females are unimportant, far from it. The amazing array of male adornments – along with the ways they show them off – have become more extreme through the generations, purely and simply because they are the ones the ladies find most attractive.

In the wild the birds are only found in New Guinea, some nearby islands and parts of eastern Australia. The remote, dense rainforest where they make their home has provided them with all they could need in terms of food and protection, which has allowed their diversity to flourish.

But while the terrain has been perfect for the birds, those seeking to study them have found it the exact opposite. The inaccessibility has ensured birds of paradise have retained a certain mystique into the present day.

A partnership between an evolutionary biologist and a wildlife photographer has gone further than most in shedding light on the secrets that lie behind the fabulous birds’ appearance.

They are one of the great wonders of the natural world

Ed Scholes and Tim Laman spent eight years carrying out 18 expeditions to the New Guinea area to document 39 species of birds of paradise, some for the first time.

“Like many people, I’m fascinated by their absolutely astounding appearances, especially the males while performing courtship displays,” says Dr Scholes, from the Cornell Lab of Ornithology.

“At times I still find it hard to believe creatures so bizarre and beautiful have evolved at all. They are one of the great wonders of the natural world.”

The duo not only had to find each species in their independent regions and habitats but also search for a male bird’s display perch. They then had to set up a camera in exactly the right position to capture the full eye-catching performance.

This involved climbing hundreds of trees and building dozens of hides to mimic a variety of surroundings.

The resulting catalogue of photographs, audio and video, called the Birds of Paradise Project, included several unique records of the elusive birds and their mating rituals.

Among their major achievements was observing the Arfak astrapia (Astrapia nigra) in the Arfak mountains, proving that the little-known species existed.

Their video also shows how they filmed the male bird’s topsy-turvy way of impressing mates, hanging upside down and sending its long tail upwards – a behaviour never captured before.

Even more surprising were the discoveries the pair made about the dance display of Wahnes’s parotia (Parotia wahnesi) or, more importantly, the correct way to view it.

The birds seem to shape-shift into another form by pushing their feathers into a tutu-like skirt, leading Dr Scholes to call it the “ballerina dance”.

But as the males are known to be displaying to females sat above them, this significant point of view was lacking in documentary evidence.

Dr Scholes and Mr Laman used three cameras, including one that looked down at the parotia, and saw two previously unseen ornamental details that were clearly crucial to the bird’s flirting repertoire.

Even though the bizarre dancing behaviour of the birds of paradise is known to have evolved, it isn’t a natural skill and juveniles begin to learn how to do it years before they develop adult plumage.

Dr Scholes and Mr Laman describe how they observed young parotias and riflebirds practising their moves and even role-playing on the BBC Two programme Attenborough’s Paradise Birds.

The mating rituals that the Birds of Paradise Project has documented have improved our understanding of the relevance of certain species’ adornments while also pointing towards areas where further revelations could be made.

“Seeing the courtship displays of Wahnes’s parotia from the perspective of the female has opened up several new avenues for exploring the displays of other species, outside of the traditional views we usually see as human observers,” Dr Scholes says.

“So we’d like to explore this question (what does the female see?) in other species.”

The pair hope to head out on another expedition to document other species of birds of paradise from the female’s point of view later this year.

Watch Attenborough’s Paradise Birds at 20:00 GMT, Thursday 29th January, BBC Two.

Artist and author Errol Fuller writes about his fascination with birds of paradise for BBC Arts

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