Thursday, April 29, 2010


For fun, let's consider pterosaur/bird landing.
Here are a few videos of birds landing.
In SLOW MOTION it is something to behold.

And here is info about pterosaurs:

"A set of Pterosaur footprints unearthed in France is the first to show one of the winged reptiles coming into land - and suggests they did so in much the same way as most modern birds.

An exceptional set of footprints preserved in 150-million-year-old rock near Crayssac in south-west France holds some answers to pterosaur behaviour. They record the moment a small pterosaur came into land, says Kevin Padian at the University of California, Berkeley.

Padian's team says the prints are similar to those produced by a landing bird. Although most pterosaur tracks show the animals walking on all fours, the first prints in the newly discovered tracks are of the rear limbs only.

That's because the pterosaur used its wings to "stall" as birds do, says the team, so that the animal's body swung up from a horizontal flight position to near vertical, enabling it to land gently on its hind feet.

"The smaller ones, like the smallest birds, are all good flappers, so they [could] 'flap-stall' to land," says Padian. Larger pterosaurs might have stalled by simply holding their wings against the airflow. Either way, the pterosaurs would have needed sophisticated neural control on a par with modern birds, the researchers say.

After the flap stall, the tracks show the animal stabilised itself with its arms, as it hopped a little way forward before it began to walk away on all four limbs.

David Martill, a pterosaur specialist at the University of Portsmouth, UK, says that although the tracks record a "small moment, perhaps no more than three seconds, in the life of a pterosaur", they offer a real insight into the lives of the ancient animals.

But Michael Habib at Chatham University in Pittsburgh, Pennsylvania, points out that the real mystery of pterosaur flight remains unsolved.

"Any flying animal larger than a large insect will need to use some kind of controlled stall or hover mechanism to land," he says, but the new track "does not give us any new information about launch".

Earlier this year Habib suggested that the largest pterosaurs took flight by using all four limbs to leap into the air – a technique similar to that used by some bats but quite unlike the take-off behaviour of modern birds.

Padian says Habib's theory may have been possible. "On the other hand, pterosaurs seem perfectly capable of standing on their back legs, so a two-legged [bird-style] take-off, whether from a standing pose or running, seems equally plausible – depending on the pterosaur."

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