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How birds rapidly evolved to have feathers, fly and sing is revealed in a major study where the genomes of 45 species of modern birds were sequenced, to generate the most reliable avian tree of life to date.

The international project charts a 'big bang' burst of bird evolution during the 10 to 15 million years after the mass extinction of dinosaurs 66 million years ago,

The period gave rise to nearly all of the 10,000-plus species of birds on Earth today.

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How birds rapidly evolved to have feathers, fly and sing is revealed in a major study where the genomes of 45 species of modern birds were sequenced, to generate the most reliable avian tree of life to date. Close-ups of the diagram can be seen in the video below

The study also suggests that the earliest common ancestor of land birds, which include parrots and songbirds as well as hawks and eagles, was a scaled predator.

The four-year project, which involved researchers from the University of Edinburgh's Roslin Institute, decoded and compared the genetic fingerprints of 45 bird species, including the woodpecker, owl, penguin, hummingbird and flamingo as well as those of three reptile species and humans. 

The vast study provides fresh insights into how bird genes differ from those of mammals, and the biological mechanisms that gave rise to the vast diversity among birds.

Decoding the genomes enabled the experts to investigate at which point in each species' history specialised characteristics developed, such as feathers, flight and song.

Scientists completed the largest whole genome study of a single class of animals to date by mapping the tree of life for birds. Avian genetic samples from Louisiana State University's Museum of Natural Science, which has one of the largest vertebrate tissue collections in the world (shown), were used for this study

The study also suggests that the earliest common ancestor of land birds, which include parrots and songbirds as well as hawks and eagles (stock image), was a scaled predator

How birds rapidly evolved to have feathers, fly and sing is revealed in a major study where the genomes of 45 species of modern birds were sequenced, to generate the most reliable avian tree of life to date. A simplified version is shown

They found that birdsong evolved independently at least twice, for example. 

Parrots and songbirds gained the ability to learn and mimic vocal activity independently of hummingbirds, despite sharing many of the same genes.

This is surprising because animals with similar characteristics usually share a close common ancestor.

The findings are relevant because some of brain processes that are involved in birds singing are also associated with human speech production. 

More than 200 scientists contributed to the Avian Phylogenomics Project, and the findings are published in 23 scientific papers, including eight in the journal Science.

As part of the study, researchers from the University of Kent found that chickens and turkeys experienced fewer large genomic changed than other birds, as they evolved from their dinosaur ancestor.

Professor Darren Griffin explained that the chicken and turkey lineages have undergone the fewest number of changes compared to their ancient avian ancestor thought to be a feathered dinosaur.

One report by Dr Ed Green, of University of California, describes the sequencing of three crocodilian genomes - the American alligator's, the saltwater crocodile's, and the Indian gharial's - which represent birds' closest living relatives.

Dr Green said: 'The molecular evolution of birds is much faster than it is in crocodiles, turtles and other reptilian lineages. So this avian lineage seems to be faster than other reptiles, but not faster than mammals.'

By studying the genes of penguins as part of the huge study, scientists at the China National Genebank in Shenzhen discovered that penguins have a vast number of genes responsible for creating the raw material needed for feathers - proteins known as beta-keratins.

They carry more genes for a particular type of beta keratin than any other bird and it is thought this is what allows them develop their thick plumage of short, stiff feathers that keep them warm. 

The scientists also discovered that penguins have a gene called DSG1, which in humans is known to be involved in a dermatological disease characterised by thick skin on the palms and feet. 

Scientists discover that modern flyers descended from DINOSAURS

Frozen samples of muscle tissue from bird species (pictured) collected by the Smithsonian Institution were the source of DNA extracted in Duke University labs. The DNA was then sent to BGI in China for full genome sequencing

One report by Dr Ed Green, of University of California, and colleagues describes the sequencing of three crocodilian genomes - the American alligator's, the saltwater crocodile's (pictured), and the Indian gharial's - which represent birds' closest living relatives

It's believed these genes may help the penguins develop a uniquely thick skin compared to other birds.

Building on the huge project, scientists at the National Avian Research Facility in Edinburgh have created 48 open access databases to share and expand on the information associated with the birds' genomes.

They hope that researchers from around the world will continue to upload their own data, offering further insights to the genetics of modern birds.

Such information will be useful for helping scientists to understand why infectious diseases, such as bird flu, affect some species but not others.

Professor David Burt, of the National Avian Research Facility, said: 'This is just the beginning.

'We hope that giving people the tools to explore this wealth of bird gene information in one place will stimulate further research.

'Ultimately, we hope the research will bring important insights to help improve the health and welfare of wild and farmed birds.' 

Adélie penguins have eight genes for metabolising fat, which may allow them to adapt quickly to warmer conditions but could leave them struggling in colder weather when food sources are more scarce