Dinosaurs 'used feathered limbs to run up steep slopes'

Small dinosaurs used the first feathered wings to clamber up steep slopes, according to a controversial theory that could explain the origin of flight in birds.

The wings, rather than being used as aids for gliding or jumping through the air, are thought to have increased the grip of the dinosaur's feet on the ground. Scientists have tested the idea on running partridges, which frequently flap their wings frantically to run head-long up vertical surfaces. They believe their theory could explain the evolution of feathered flight.

There is wide agreement that some dinosaurs grew feathers, probably for insulation, and that these were later adapted by the earliest ancestors of the birds for flying, but how powered flight came about is still open to question. One theory is that feathered forelimbs were used by tree-dwelling dinosaurs to glide from one branch to another. Another idea is that they were used to keep a jumping dinosaur in the air for longer.

Professor Kenneth Dial, of the University of Montana in Missoula, has found evidence to back up his idea that the first feathered wings were designed to increase the traction between the animal's feet and the ground.

In trying to explain the evolution of flight, scientists have to address the problem of what benefit the partially evolved wing, which would be of little use for flying, might have conferred on an animal. "It turns out that the proto-wings – precursors of wings that birds have today – actually acted more like a spoiler on the back of a race car to keep the animal sure-footed even while climbing up nearly vertical surfaces," Professor Dial said.

To test his idea, Professor Dial filmed partridges scrambling up slopes to see how they used their wings to increase ground traction, which was measured by instruments that detected the g-forces of a bird's body on the floor. The study, published in the journal Science, found that newly hatched chicks still unable to fly could nevertheless use their stubby, undeveloped wings to climb up a 50-degree incline. Slightly older birds used their flapping wings to "walk" up vertical slopes, while fully grown adults could even grip overhanging surfaces – defying gravity using the downward movement of their wings.

Professor Dial said the way the partridge used its wings to surmount difficult obstacles was a remnant of a similar behaviour invented by the early ancestors of birds, to escape predators. "A significant portion of the wing-beat cycle involves ... forces that push the bird toward the inclined substrate, permitting animals to run vertically," Professor Dial said. "In the proto-bird, this behaviour would have represented the intermediate stage in the development of flight-capable, aerodynamic wings."

The earliest ancestors of birds are believed to have evolved from feathered dinosaurs 225 million years ago.

Start your day with The Independent, sign up for daily news emails
Arts and Entertainment
Buttoned up: Ryan Reynolds with Helen Mirren in ‘Woman in Gold’
filmFor every box-office smash in his Hollywood career, there's always been a misconceived let-down. Now he says it's time for a reboot
News
people
News
Actress Julianne Moore wins the Best Actress in a Leading Role Award for 'Still Alice' during the 87th Annual Academy Awards in Hollywood, California
people
Sport
Ross Barkley
footballPaul Scholes says it's time for the Everton playmaker to step up and seize the England No 10 shirt
News
'We will fix it': mice in the 1970s children’s programme Bagpuss
science
Life and Style
2 Karl Lagerfeld and Choupette
fashion
ebooks
ebooksA special investigation by Andy McSmith
  • Get to the point
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Customer Service Executive

£18000 - £22000 per annum: Recruitment Genius: This is an exciting opportunity...

Recruitment Genius: Retail Buyer / Ecommerce Buyer

£30000 - £35000 per annum: Recruitment Genius: Working closely with the market...

Recruitment Genius: Sales Executive - CAD Software Solutions Sales

£20000 - £50000 per annum: Recruitment Genius: A reputable company, famed for ...

Ashdown Group: Client Accountant Team Manager - Reading

Negotiable: Ashdown Group: The Ashdown Group has been engaged by a highly resp...

Day In a Page

War with Isis: Iraq declares victory in the battle for Tikrit - but militants make make ominous advances in neighbouring Syria's capital

War with Isis

Iraq declares victory in the battle for Tikrit - but militants make make ominous advances in neighbouring Syria
Scientists develop mechanical spring-loaded leg brace to improve walking

A spring in your step?

Scientists develop mechanical leg brace to help take a load off
Peter Ackroyd on Alfred Hitchcock: How London shaped the director's art and obsessions

Peter Ackroyd on Alfred Hitchcock

Ackroyd has devoted his literary career to chronicling the capital and its characters. He tells John Walsh why he chose the master of suspense as his latest subject
Ryan Reynolds interview: The actor is branching out with Nazi art-theft drama Woman in Gold

Ryan Reynolds branches out in Woman in Gold

For every box-office smash in Ryan Reynolds' Hollywood career, there's always been a misconceived let-down. It's time for a rethink and a reboot, the actor tells James Mottram
Why Robin Williams safeguarded himself against a morbid trend in advertising

Stars safeguard against morbid advertising

As film-makers and advertisers make increasing posthumous use of celebrities' images, some stars are finding new ways of ensuring that they rest in peace
The UK horticulture industry is facing a skills crisis - but Great Dixter aims to change all that

UK horticulture industry facing skills crisis

Great Dixter manor house in East Sussex is encouraging people to work in the industry by offering three scholarships a year to students, as well as generous placements
Hack Circus aims to turn the rule-abiding approach of TED talks on its head

Hack Circus: Technology, art and learning

Hack Circus aims to turn the rule-abiding approach of TED talks on its head. Rhodri Marsden meets mistress of ceremonies Leila Johnston
Sevenoaks is split over much-delayed decision on controversial grammar school annexe

Sevenoaks split over grammar school annexe

If Weald of Kent Grammar School is given the go-ahead for an annexe in leafy Sevenoaks, it will be the first selective state school to open in 50 years
10 best compact cameras

A look through the lens: 10 best compact cameras

If your smartphone won’t quite cut it, it’s time to invest in a new portable gadget
Paul Scholes column: Ross Barkley played well against Italy but he must build on that. His time to step up and seize that England No 10 shirt is now

Paul Scholes column

Ross Barkley played well against Italy but he must build on that. His time to step up and seize that England No 10 shirt is now
Why Michael Carrick is still proving an enigma for England

Why Carrick is still proving an enigma for England

Manchester United's talented midfielder has played international football for almost 14 years yet, frustratingly, has won only 32 caps, says Sam Wallace
Tracey Neville: The netball coach who is just as busy as her brothers, Gary and Phil

Tracey Neville is just as busy as her brothers, Gary and Phil

The former player on how she is finding time to coach both Manchester Thunder in the Superleague and England in this year's World Cup
General Election 2015: The masterminds behind the scenes

The masterminds behind the election

How do you get your party leader to embrace a message and then stick to it? By employing these people
Machine Gun America: The amusement park where teenagers go to shoot a huge range of automatic weapons

Machine Gun America

The amusement park where teenagers go to shoot a huge range of automatic weapons
The ethics of pet food: Why are we are so selective in how we show animals our love?

The ethics of pet food

Why are we are so selective in how we show animals our love?