How did big Jurassic flying reptiles get off?

[struggle4progress]

Poll question: How did big Jurassic flying reptiles get off?

link

[darmok167]

1. Well, it's like this...

...when a mommy big Jurassic flying reptile and a daddy big Jurassic flying reptile meet and fall in love... :D

[supernova]

2. Is this a flashy thing holdover

from last night?

:D

[struggle4progress]

3. I can't remember

[Fire Walk With Me]

4. Ask the "6000 year" creationists. They were there

and must have records of some sort.

[skygazer]

5. Porn

[Fire Walk With Me]

6. Big Jurassic flying reptile porn.

The kind that's okay.

[skygazer]

7. Exactly

And Dino Viagra. :P

[Fire Walk With Me]

8. If your tyrannosaurus lasts longer than four hours, consult a physician.

[BreweryYardRat]

9. When you're finished acting juvenile about an interesting piece of scientific theory...

The leapfrog idea might work. Many of the heavier species might have lived near cliffs, etc, where they could have gotten airborne easily and had thermals to give them lift if they needed it.

[struggle4progress]

10. It's hard to imagine large bird-like pterosaurs launching by means other than cliff-jumping by

But the linked article also shows a putative reconstruction of another body type with a less birdlike webbing, to which the jumping hypothesis presumably applies

I don't know whether (for example) there are good skin impression fossils that support such a reconstruction, but an animal of such type would seem likely to glide (something like a flying squirrel)

Such a creature might still obtain an evolutionary advantage by gliding (rather than flying like a modern bird), for example by launching down a long hillside and sliding through the air at low elevation towards a local depression some distance away

Such a glide might quickly create an advantageous distance between the pterosaur and a would-be predator that was able to obtain high ground speeds for only a limited time: it is probably important here that the aerodynamics of gliding within a few meters of the ground are different than the aerodynamics of higher gliding