Still spreading shinola, CTD?

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I note that two isn't a very large number. Still, it's quite the confession for RAZD, who previously claimed there couldn't be two of anything.
Yes, they are two different examples, examples that are not identical.

Curiously my original argument was that there were no two identical objects in reality, and I still have not seen any evidence of two identical objects. Thus "two" is an abstract concept, one that does not exist in reality, no matter how useful the abstract concept is to calculate things like decay rates.

Nor do I need to provide more examples when your question implied there were none. But there are MANY, and if you like, we also have gliding frogs ...

[Linked Image]


http://en.wikipedia.org/wiki/Rhacophorus_nigropalmatus
http://www.agpix.com/view_caption.php?image_id=44922&keyword=rainforest
http://www.cpbrestvankempen.com/paintingspc25.html

... and gliding snakes ...

http://en.wikipedia.org/wiki/Chrysopelea
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Chrysopelea are called "flying snakes", though this is misleading, as they actually glide instead of fly. This is done by flattening their bodies to up to twice their width from the back of the head to the vent. These snakes can glide better in comparison to flying squirrels and other gliding animals, despite lacking any limbs, wings or wing-like projections.
This in spite of having exactly the opposite aspect ratio of airplane wings ...

To see videos of these snakes in flight see:
http://homepage.mac.com/j.socha/video/video.html

Many organisms have evolved ways to fly, float or glide through the air, from spiders, to fish, to frogs to snakes. Not all of them have aerodynamic wings, rather they have adapted the materials they have at hand to "try a hand" at flight. By the change in hereditary traits in populations from generation to generation.

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Maybe there's hope he'll learn to count to even bigger numbers like 3 or 5.
Anyone paying attention will note that this is an insult intended to distract the reader from the fact that CTD did not say anything about his implication being falsified, nor anything about the fact that these, now several examples, as well as the bat fossil in question, show clear ways that such systems can evolve from existing equipment in existing organisms.

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I added bold so folks can clearly see that both stories involve gliding. (Hopefully this explanation of bold letters will suffice.)
There is at least one more theory as well, that the proto-wings allowed the owners to climb steep slopes and trees by running up them while using their proto-wings to create "lift" holding them against the surface. Curiously young grouse do this before their wings are developed enough that they can fly:

Wing-Assisted Incline Running and the Evolution of FlightCuriously the wing beating pattern is different in juvenile birds than in flying adults:

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This hypothesis is based upon the observation of ground-dwelling birds that use wing-assisted incline running (WAIR). This type of locomotion is not often seen, usually occurring in very short bursts when a bird attempts to escape a predator. By rapid flapping of the wings, the bird can create enough traction to run up a vertical surface.

Kenneth Dial has been studying WAIR for several years. In the current study he tested chukar partridges (and them’s good eatin’!) from first-day hatchlings to adult birds. He found that even newly hatched birds will climb ramps using their wings to paddle along and will leap off a drop flapping the wings to (poorly) control descent. Older birds become more adept at climbing in this manner and controlling descent on the other side of the ramp, until adult birds are able to climb a vertical surface and take off into powered flight.

Dial found the the orientation of the wingbeat remains constant from day 8 to adulthood and is different from that used in flight, and proposes that this wingbeat used in WAIR is a fundamental wing-stroke that predates and is ancestral to flight.
That would be a transitional behavior between running and flying, one with a clear survival advantage, as well as one that is observed in existing birds as they develop from down covered arms to fully feathered wings. Curiously this behavior does not include trying to glide on the developing wings.

Such flapping while falling to control descent is seen in many young birds, Wood Ducks would be an example many could be familiar with.

It may seem like a step aside from the topic here, but modern swimmers have also learned that they can swim faster by spreading their fingers and waving their hands sideways to the stroke, creating a virtual hand "bigger" than the actual one. It creates extra drag on the hand, which translates into more push for the swimmer.

So yes, I believe that wings evolved for flight and not for gliding. Perhaps CTD can prove that I'm wrong by demonstrating how wings actually developed, with evidence and substantiation, and using a clear dependency on non-flapping gliding. Note that the old tree up and tree down do not rule out this flapping assisted behavior.

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Now if you'd offer something on-topic, you might point me to a missing link between bats and whatever you think they evolved from. 20 to 25 per cent of all mammalian species - that's a pretty big chunk to just hang out to dry, so to speak. Particularly after you stressed the importance of finding the fossils.
The good old, when everything else fails, god-of-the-gaps argument, eh?

http://www.si.edu/Encyclopedia_SI/nmnh/batfacts.htm
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Evidence for bat-like flying mammals appears as far back as the Eocene Epoch, some 50 million years ago; however, the fossil record tracing bat evolution is scanty. Based on similarities of bones and teeth, most authorities agree the bat's ancestors were probably insect eating placental mammals, possibly living in trees, and likely the same group that gave rise to shrews and moles. Bats are not rodents and are not even closely related to that group of mammals.
So we don't know, and that means we don't know.

Meanwhile, astute readers will note that the existence of this gap in the fossil record does not remove the evidence of transitions -- intermediate varieties in Darwin's words -- that we have already seen in profusion, nor does it show that CTD's original claim of ...

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For example, even the true believer has only a small handful of "transitionals" available, and must imagine all the rest.
... has not been completely, utterly and totally falsified. We have several million intermediate fossils already posted on this thread, and the full amount of biological and fossil evidence for "intermediate varieties" has hardly been considered.

So, as far as the ability to "learn to count to even bigger numbers like 3 or 5" is concerned, CTD better evolve a few more fingers ...

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So where are the critters that are intermediate between bats and their ancestors? Do you find them?
Anyone want to bet that if an older fossil was found tomorrow in both a predicted more intermediate form between this bat fossil and some tree-climbing insectivorous shrew-like animal, that CTD would ask where the next intermediate is?

Meanwhile the issue remains unchallenged by CTD that this bat fossil does in fact show several characteristics that are intermediate between modern bats and what an ancestral mammal that did not have membranous wings would look like. Is this imagination? Or is it applying the evidence of life we have around us to develop working hypothesis that can be tested?

That IS what science does when it comes to a question where the answer is "we don't know" after all.

Enjoy.

Last edited by RAZD; 09/19/08 10:22 PM. Reason: abstracted
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