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Re: flights of fancy (or "I'm brave, but I'm chicken****")
In a message dated 95-12-05 19:02:48 EST, firstname.lastname@example.org
(Mickey Rowe) writes:
>Ok, this is (hopefully) my last word in this thread:
>> Using hyperbole here doesn't help the situation and makes it sound
>> as if you're raving. "Gibberish"? I hardly think so.
>That's ok, George. I'm not so much trying to convince you so much as
>I'm trying to make sure that your audience appreciates that your
>pronouncements aren't the gospel you appear to me to make them out to
I didn't know this was a problem for you.
>>> Our moment of inertia around our vertical axis is miniscule compared
>>> to that of a theropod according to contemporary reconstructions.
>> So consider a human runner with a large log horizontally strapped to
>> his or her midsection.
>IMHO, that's not even funny. But in any case, another point I really
>should have hammered home before is that human arms are attached
>directly above the human's center of mass in the antero-posterior
>direction. Theropod forelimbs are attached well forward of their
>center of gravity, so once again we have reason to expect that arm
>movements in running theropods will not approximate arm movements in
>>> Although many of the leg motions will probably be similar for the
>>> two forms ...
>> See? It's not "absolute gibberish" after all.
>In the context of our discussion it IS absolute gibberish. We were
>talking about whether or not feathered arms would hinder a running
>theropod. You say that humans speak to this point. If you don't yet
>see that they don't then I fear you never will. I'll just keep
>working on the next generation...
If you don't see that they _do_ speak to this point...etc., etc.
>>> Maybe it was more efficient for the animal to tuck in its arms
>>> during a high speed chase. Maybe that's the reason for that
>>> adaptation (exaptation?).
>> No, the reason is more likely to be that _Deinonychus_ had a volant
>> ancestor somewhere in its family tree. Why is this so difficult to
>Mainly because the forelimbs of _Deinonychus_ don't look at all like
>modified wings to me. They certainly don't look like modified bird
>limbs. However, in the final analysis, I haven't been trying to
>convince you that you're wrong (as you've been doing to the rest of
>the world). I've only been trying to convince you that your apparent
>certainty is misplaced.
The forelimbs of _Deinonychus_ are DEAD RINGERS for the forelimbs of
_Archaeopteryx_, bone for bone for bone. Where have you been?? How many
papers does John Ostrom have to publish on this before it sinks in?
>> Perhaps I'm wrong, and feathers on the forearms and hands _would_
>> help a running theropod capture more prey, but I don't think
>> anything you've said in this posting or in the previous posting is
>> terribly convincing of this thesis.
>We were mainly talking about evading predators, actually. Have YOU
>ever chased a roadrunner?
If I had to rely on catching roadrunners for a living, I'd be extinct. But
just think--maybe roadrunners would be _even faster_ without their feathers
(but then they wouldn't be ale to fly).