Featured Research

from universities, journals, and other organizations

What Use is Half a Wing in Evolution of Birds?

Date:
May 1, 2006
Source:
American Institute of Biological Sciences
Summary:
An article by Kenneth P. Dial and two co-authors in the May 2006 issue of BioScience summarizes experimental evidence indicating that ancestral protobirds incapable of flight could have used their protowings to improve hindlimb traction and thus better navigate steep slopes and obstructions.

Ken Dial, who is a professor of vertebrate morphology and a licensed commercial pilot, holds an adult chukar partridge in his flight lab at the University of Montana.
Credit: K.P. Dial, University of Montana

Biologists have long argued about how birds evolved the ability to fly, because it is not immediately evident what improvement in fitness would result from ancestral, partly evolved wings. Two theories have recently dominated the debate: one postulates that flight evolved in tree-dwelling ancestors that used their forelimbs to help them glide, while the other considers ancestral birds to be terrestrial dinosaurs that developed powered flight from the ground up.

Related Articles


An article by Kenneth P. Dial and two co-authors in the May 2006 issue of BioScience summarizes experimental evidence indicating that ancestral protobirds incapable of flight could have used their protowings to improve hindlimb traction and thus better navigate steep slopes and obstructions. By using their protowings in this way, they would presumably have had an advantage when pursuing prey and escaping from predators.

Dial and colleagues performed experiments on several species of juvenile galliform (chicken-like) birds, concentrating on chukar partridges. Chukars can run 12 hours after hatching, but they cannot fly until they are about a week old. Even before they are able to fly, however, the birds flap their developing wings in a characteristic way while running, which improves their ability to climb steep slopes and even vertical surfaces. Dial and colleagues have named this form of locomotion "wing-assisted Iincline running" (WAIR). After they are able to fly, chukars often use WAIR in preference to flying to gain elevated terrain, and exhausted birds always resort to WAIR.

Dial and colleagues describe experiments showing that if the surface area of chukar wings is reduced by plucking or trimming the feathers, WAIR becomes less effective for climbing slopes. Dial and colleagues propose that incipiently feathered forelimbs of bipedal protobirds may have provided the same advantages for incline running as have now been demonstrated in living juvenile birds. Their work thus supports a new theory about the evolution of flight in birds. WAIR, which the authors believe to be widespread in birds, appears to offer an answer to the question first posed by St. George Jackson Mivart in 1871: "What use is half a wing?"



Story Source:

The above story is based on materials provided by American Institute of Biological Sciences. Note: Materials may be edited for content and length.


Cite This Page:

American Institute of Biological Sciences. "What Use is Half a Wing in Evolution of Birds?." ScienceDaily. ScienceDaily, 1 May 2006. <www.sciencedaily.com/releases/2006/05/060501100950.htm>.
American Institute of Biological Sciences. (2006, May 1). What Use is Half a Wing in Evolution of Birds?. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2006/05/060501100950.htm
American Institute of Biological Sciences. "What Use is Half a Wing in Evolution of Birds?." ScienceDaily. www.sciencedaily.com/releases/2006/05/060501100950.htm (accessed October 25, 2014).

Share This



More Fossils & Ruins News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Fossil Treasures at Risk in Morocco Desert Town

Fossil Treasures at Risk in Morocco Desert Town

AFP (Oct. 23, 2014) Hundreds of archeological jewels in and around the town of 30,000 people prompt geologists and archeologists to call the Erfoud area "the largest open air fossil museum in the world". Duration: 02:17 Video provided by AFP
Powered by NewsLook.com
Oldest Bone Ever Sequenced Shows Human/Neanderthal Mating

Oldest Bone Ever Sequenced Shows Human/Neanderthal Mating

Newsy (Oct. 23, 2014) A 45,000-year-old thighbone is showing when humans and neanderthals may have first interbred and revealing details about our origins. Video provided by Newsy
Powered by NewsLook.com
Weird-Looking Dinosaur Solves 50-Year-Old Mystery

Weird-Looking Dinosaur Solves 50-Year-Old Mystery

Newsy (Oct. 23, 2014) You've probably seen some weird-looking dinosaurs, but have you ever seen one this weird? It's worth a look. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins