Sunday, February 20, 2011

Pole Vaulting Dinosaurs, How the Pterosaur Started Flight


Did the ancestors of birds pole vault before into flight. British researchers have uncovered evidence of a pole vaulting dinosaur, one of the largest pterosaurs, the size of a giraffe,  that used a technique similar to pole vaulting to launch itself into the air.

Dorygnathus flying © Linda Bucklin - iStockphoto
Credit: The British Council

TOO HEAVY
Sometimes research is a useful corrective to conventional wisdom. When Dr Mark Witton, a Research Associate at Portsmouth University’s School of Earth & Environmental Sciences, and Dr Michael Habib of Chatham University, Pennsylvania, read that the largest pterosaurs were too big to fly, they knew something was missing.

‘Last year,’ says Dr Witton, ‘a study came out which said that no animal larger than 4 or 5 metres across the wings could fly, and could weigh no more than 40 kilograms. Then this year, another study came out that said that the largest pterosaurs weighed about half a ton and that would make them too heavy to fly.’
 © Portsmouth University
Credit: The British Council




WINGS
What seemed most unusual to Dr Witton, is that a pterosaur skeleton is ‘basically a pair of wings’ with a head on the front. And though they don’t have complete skeletons for the larger pterosaurs, their bodies seemed to be equally adapted for flying. ‘What’s happened in the studies suggesting that they couldn’t fly was more a misunderstanding of the mechanics of pterosaur flight, rather than their actual flight ability’ says Dr Witton.

SIZE AND FLIGHT
Research by Dr Habib suggested that as pterosaurs get bigger, their arm bones increase in size dramatically. ‘If you scale up a small bird to a big bird, the wing bones are proportionately very similar, but that’s not the case with their leg bones at all. Their leg bones become very robust and strong and this appears to be related to take off.’ Whether it’s a pterosaur, an insect or bird, the speed and power for takeoff comes from walking limbs.

(c) Portsmouth University
Credit:  The British Council

This suggested to Dr Habib that pterosaurs are using their forelimbs to take off. ‘But’, says Dr. Witton, ‘he proposed this idea of the quadripedal launch, a ‘pole-vaulting’ idea. He made almost a throwaway comment in his paper saying that this may explain why some pterosaurs got so much larger than modern birds.’

In their recent paper, they explored the idea arguing that this is probably why pterosaurs can get so enormous. The largest fossil birds on record are about 7 metres across the wings, which is significantly smaller than the 10 metres across, and a quarter of a ton, which is what we think the larger pterosaurs weighed.’

Source: The British Council

1 comment:

  1. This article is like a hippy trip back to the seventy’s with its cosmic pictures and reality warping statements from its new wave scientists.

    According to National Geographic or the San Diego Zoo a giraffe has a mass of 794 to 1,270 kg or 600 to 1,360 respectfully. Scale up any large flying bird or bat to the size of the Quetzalcoatlus and you are going to get a mass value that is well over a ton. So how do you get a ton animal to fly? Simple, just take a few hits of whatever Michel and Mark are smoking to join them on their magical mystery tour.

    Michel and Mark’s ability to dismiss all notions of reality has led the public to a fantasy world regarding the science of flight. I wonder how much misguidance has led to the production of the fantasy movies showing people riding giant pterosaurs and flying birds. As much fun as these notions are, I have to wonder about the damage to the advancement of science when the presentation of evidence and the scientific application of physics and mathematics are force to compete with magic.

    Michel and Mark want us to believe that all the pterosaurs had to do was leap into the sky, very much like superman did when he would say up, up, and away before flying up into the sky. How did science get dumb down to the level of the poor reasoning ability of an eight year old?

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