Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New Study Suggests Missing Link that Explains How Dinosaurs Learned to Fly


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.
Photo Credit: K.P. Dial, University of Montana

Two-legged dinosaurs may have used their forelimbs as wing-like structures to propel themselves rapidly up steep inclines long before they took to the skies, reports a University of Montana researcher in the January 17 issue of the journal Science. The new theory adds a middle step that may link two current and opposing explanations for how reptiles evolved into flying birds.

According to Kenneth Dial, author of the report, the transition from ground travel to flight may have required a "ramp-up" phase in which rapid movement of the animals’ front appendages actually forced its body downward to gain more foot traction as it made its way up increasingly vertical slopes.

"The big dilemma has been, ’How do you explain the partial wing?,’" says Dial, who is a professor of vertebrate morphology and ecology. "It turns out the proto-wings-precursors to wings 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," he said.

"The development and role of movement in animals is critical to every aspect of their lives," says William Zamer of the National Science Foundation (NSF), the agency that funded the study. "The results may also one day help humans design better vehicles for both land and air travel."

NSF is an independent federal agency that supports fundamental research and education in all fields of science and engineering.

The evolution of flying vertebrates has been a bone of contention since the 1800’s. One school, which embraced the cursorial theory, argued that two-legged, ground-dwelling animals developed feathered wings that allowed them to become airborne. The opposing school, which favored the arboreal theory, held that flight originated in tree-dwelling animals that leapt from limb to limb and eventually developed gliding structures to soften their landings. For a century-and-a-half, each camp has tendered evidence to challenge the opposing theory.

The solution, Dial says, may lie in an ordinary flapping behavior, which he calls "wing-assisted incline running," or WAIR, found in many modern-day hatchling and adult birds. "Although this behavior is common in nature, " he writes, WAIR’s role in the evolution and survival of birds "has remained unappreciated" because it happens in short bursts that are difficult to study in the wild.

So, Dial, who is also a licensed commercial an instrument-rated pilot, applied to partridges devices that sensed g-force and used high-speed film to document wing orientation in a laboratory setting. He found that newly hatched birds, yet unable to fly, successfully used WAIR to climb a 50-degree incline. Slightly older birds used WAIR to climb a 90-degree, or straight-up, surface, and adult birds used their wings literally to defy gravity. Wing flapping kept their bodies secured to the underside surface of a 105-degree overhang.

"A significant portion of the wing beat cycle involves...forces that push the bird toward the inclined substrate, permitting animals to run vertically," Dial observed.

Dial proposes that WAIR in modern-day birds is a remnant of their prehistoric ancestors. "In the proto-bird, this behavior would have represented the intermediate stage in the development of flight-capable, aerodynamic wings." Further re-orientation of the wings could then allow birds to make successful ascents into the air as well as safe landings.

Experts believe birds evolved from a common ancestral protoavis dinosaur some 225 million years ago during the Mesozoic era. As the continental land mass broke apart, birds inhabited all corners of the Earth. While most bird species were wiped out with the dinosaurs 65 million years ago, many scientists consider birds the only true living relative of the dinosaurs.


NSF is an independent federal agency that supports fundamental research and education across all fields of science and engineering, with an annual budget of nearly $5 billion. NSF funds reach all 50 states through grants to nearly 2,000 universities and institutions. Each year, NSF receives about 30,000 competitive requests for funding, and makes about 10,000 new funding awards. NSF also awards over $200 million in professional and service contracts yearly.

Receive official NSF news electronically through the e-mail delivery system, NSFnews. To subscribe, send an e-mail message to In the body of the message, type "subscribe nsfnews" and then type your name. (Ex.: "subscribe nsfnews John Smith")

Leslie Fink | NSF
Further information:

More articles from Life Sciences:

nachricht Don't Give the Slightest Chance to Toxic Elements in Medicinal Products
23.03.2018 | Physikalisch-Technische Bundesanstalt (PTB)

nachricht North and South Cooperation to Combat Tuberculosis
22.03.2018 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Space observation with radar to secure Germany's space infrastructure

Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.

The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

New solar solutions for sustainable buildings and cities

23.03.2018 | Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

Latest News

For graphite pellets, just add elbow grease

23.03.2018 | Materials Sciences

Unique communication strategy discovered in stem cell pathway controlling plant growth

23.03.2018 | Agricultural and Forestry Science

Sharpening the X-ray view of the nanocosm

23.03.2018 | Physics and Astronomy

Science & Research
Overview of more VideoLinks >>>