Giant flying reptiles took off by running along on all four limbs rather than using a bird-like method to get airborne, according to a new study by Michael Habib.

“Using all four legs, it takes less than a second to get off of flat ground, no wind, no cliffs,” says the Johns Hopkins scientist (press release). “This was a good thing to be able to do if you lived in the late Cretaceous period and there were hungry tyrannosaurs wandering around.”

Habib thinks pterosaurs – which are definitely not dinosaurs – had much stronger ‘arms’ than ‘legs’. Comparing the bone strength of birds and pterosaur species he suggests that the reptiles folded their wings and hobbled around on their knuckles and did what would probably have been a highly comical series of “leap-frogging long-jumps” before sticking out their wings and taking off.

“They kind of pitch forward at first, the legs kick off first, then the arms take off,” he says (AP).

Not everyone is convinced. Sankar Chatterjee, of Texas Tech, told MSNBC he still believes they either jumped off cliffs or ran down and incline on two legs to get flying. However Mark Witton, of the University of Portsmouth, says he’s behind Habib:

The idea that pterosaurs were weather- or topography-dependent for takeoff and that they weren’t strong flapping fliers – being essentially giant gliders – just doesn’t make any sense. For one thing, the biggest pterosaurs, like the 500-pound critters Mike’s been playing with, are often found miles and miles and miles from the nearest cliff:

… In fact, Mike’s research was a big relief to me: My own research was pointing to the very controversial conclusion that some of the biggest pterosaurs were massing in the 250-kilogram / 500-pound ballpark, so when he told me that he’d found a way to get such a critter into the air I was very happy.

The research has been published in Zitteliana, but doesn’t appear to be online.

Image: Mark Witton.