This is almost as gutting as "T Rex was a scavenger"

http://www.physorg.com/news142086647.html

That "scientist" needs to go watch some people hang-gliding.

One researcher, basing it on wing size and weight.

The one's causing flack (the opposition) say...
How dare these other people think that those have something to do with it.

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Numbers are not case sensitive. (me)

Hang-gliders have exactly the problem he describes: they can't get airborne from level ground without a headwind, and they can't stay up without access to rising air.

Grant Hutchison

Eagles may soar, but Pterosaurs don't get sucked into jet-engines.

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin
"Your right to hold an opinion is not being contested. Your expectation that it be taken seriously is." -- Jason Thompson
Meet the OOONG TOE.

Hang Gliders can't flap their "wings" either. Perhaps it was a bad analogy. But then again so was his equating it to albatrosses. Is it possible that the wing folds at different angles to allow a more rapid upbeat in the wing stroke? Did he model from fossil remains? My opinion is that he saw the Discovery channel episode that saw them fishing in the open ocean and came to some poor conclusions or simply needed to have some justification for tormenting those poor albatross.

What I don't get is how they took off.

He says take-off flapping speed is higher than flying flapping speed.
Then he says Pterosaurs couldn't achieve the latter.

Huh??

Does this mean they were limited to cliff faces and trees only? If so, that's a pretty precarious existence.

You have to sustain in-flight flapping, if you want to sustain flight; whereas the take-off flap is a short burst of activity during which you can go anaerobic if necessary. The difference between a sprint and a marathon.
Albatrosses are a good example: they're pretty hopeless at getting off the ground without a head-wind, and sometimes have to give up on one take-off run and have a rest before making another attempt. They can get stuck on the surface at sea, sometimes for days, if the wind drops while they're in the water; and they flap only very rarely while in the air, spending a lot of time looking for lift by dynamic soaring in the rising air displaced by the front faces of waves.
What this fella seems to be saying (as far as I can make out from the link) is that the pterosaur, with worse wing-loading than an albatross, couldn't get into the air without a head-wind, and couldn't gain altitude by flapping without some source of rising air.

Grant Hutchison

But not necessarily unworkably so. Every class of tetrapods includes species that have adapted to that kind of lifestyle.

Isn't that what giant condors do? Take off from cliff faces?

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The scientist in the story is wrong. The atmosphere was denser at the time. So his experiments fail.

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Not when they're eating carrion, unless the carrion has died conveniently at the top of a cliff.
A good way to catch a condor is to dump a dead goat on flat ground, and surround it with fence posts a few metres away. On a still day, the condor drops in to feed, but then finds itself with an inadequate take-off run in all directions.

Grant Hutchison

Maybe why that was why the Pterosaurs got so big, to provide reserves for those days when they had to wait it out. Large animals in general have to eat less often then small animals.

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No way!
And I curse 10 min traffic jams..

You seem to know a suspicious amount about trapping condors by the way

Nauthiz: Yeah, true. 'Puffin' went through my mind as soon as I'd posted.

Robinson: The atmosphere was denser? Epic fail on his part then.

I also once ate a puffin. Does this mean I'm a Bad Person?

Grant Hutchison

Its a battle of the experts!

http://www.abc.net.au/science/news/a...sh_1483770.htm
Here is some interesting,semi-speculation on how they COULD soar.

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You ate the condor too?

Mmmmmmm

tastes like turkey-bacon

Because of preservational bias, most fairly complete specimens have been found in the chalks of Kansas which represent a marine setting well out from shore.

see Oceans of kansas

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(By the way, I hate it that so many papers in the areas of planetary science and geology are not easily available to the dreaded "non-subscribers". It is like they are screaming at me: "YOU CAN'T HANDLE THE TRUTH". Good, I feel better now.)

"Quaerendo inventis"

This is another case of an "expert" not taking everything into account. Just like the one who claimed that bumble bee wings couldn't fly.
Pterosaurs had hollow bones, aerodynamic skulls and, more to the point, wings. They ranged from sparrow sized up to the largest winged creatures that have ever existed, with a 12 meter wingspan. They were incredibly successful and survived for millions of years. You don't do that by being badly designed.

Expert... PAH!

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This is not an idea to be tossed aside lightly - it should be thrown with great force

That one's actually a myth.
The expert involved in the bumble bee story was pointing out that they wouldn't be able to fly if their wings were simply flat plates; from which he deduced that there must be some sort of aerofoil in operation, despite superficial appearances.

Grant Hutchison

I think this animal is a pretty clear case of specialised evolution to do one job.

__________________
(By the way, I hate it that so many papers in the areas of planetary science and geology are not easily available to the dreaded "non-subscribers". It is like they are screaming at me: "YOU CAN'T HANDLE THE TRUTH". Good, I feel better now.)

"Quaerendo inventis"

This is kind of like saying that plesiosaurs and pliosaurs couldn't swim, because we don't know exactly how they moved their flippers; as is, how they did it is indeed controversial, as it was apparently unique among swimming vertebrates.

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"Call me old-fashioned, but I think fire is magic. And it scares me a lot."

--The State

And the Tylosaurs as well:



From Oceans of Kansas; Everhart

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(By the way, I hate it that so many papers in the areas of planetary science and geology are not easily available to the dreaded "non-subscribers". It is like they are screaming at me: "YOU CAN'T HANDLE THE TRUTH". Good, I feel better now.)

"Quaerendo inventis"

God, that's a mean mother.

Mr. 'Scientist' needs to talk to some radio-controlled modelers.

A number of them have built R/C Pterosaurs and thermalled them just fine after they worked out how to use the head as a rudder.

http://www.youtube.com/watch?v=ucE-xUIQ_rI

Not that they would have had to thermal much if they stayed at the coastlines or mountain ranges where they could take advantage of ridge lift (or slope soaring as we call it...)

Although the atmospheric pressure may have been a little higher than the present day, the partial pressure of oxygen was lower at the time pterosaurs first appeared (the Triassic), and rose to match the present day only around the time they became extinct (the end of the Cretaceous).
Peter Ward, in his book Out of Thin Air, claims that the low oxygen pressures may have helped drive the evolution of the dinosaurs (in particular the efficient counterflow lung that birds have inherited). But those low oxygen levels would certainly add to the problems of a heavy flyer.

Grant Hutchison

Recent evidence points towards much higher oxygen levels in the past, which means denser atmosphere.

The issue is far from settled of course.

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Interesting. Can you give a reference that shows this for the Mesozoic?
Ward uses Robert Berner's GEOCARBSULF (770kB pdf) model, from 2005.

Grant Hutchison

It would be an entire topic to discuss evidence for oxygen levels in the history of the earth.

Yes, I have a lot of information. But little time.

The issue is also contentious.

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