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Creation/Evolution and Dinosaurs



Cross-posted from the SKEPTIC mailing list.


______________________________ Forward Header __________________________________
Subject: Creation/Evolution
Author:  skeptic@listproc.hcf.jhu.edu at smtp
Date:    30/7/1995 11:32 AM


roy handley <karen@handley.demon.co.uk> writes:

> Thank you for the eloquent descripton of the reptillian
> characteristics of Archaeopteryx. I had no idea that there was so much 
> known about this incredible creature

I highly recommend the article from Scientific American, previously 
cited. (May, 1990)

> On the theory/hypothesis (delete whichever is inapplicable) that 
> dinosaurs were essentially reptiles, I thought that they were
> considered to be warm blooded and that this accounts for them being 
> much more physically active than was previously thought.

I'm not a paleontologist, but my understanding is that this is still 
an active area of debate.  Since we have no living specimens to 
examine, we are forced to attempt to deduce this from such things as 
body size, predator-prey ratios, trackways, and so on.

> Presumably, from what you were saying they diverged into warm blooded 
> birds and cold blooded reptiles. As a matter of interest, are there
> any warm blooded reptiles alive today 

Not to my knowledge.  It may be that the "original" function of 
feathers, before they became useful for flight, was as insulation, 
which would have made it easier for these creatures to regulate their 
body temperature.

Climate and surface to volume ratios would also have made a 
difference, and it may be that larger dinosaurs were warm-blooded, 
while smaller ones were not.  There may be no way to answer this 
question definitively.

>> But, since seismosaurs obviously did have a neck 
>> that long, they must have had the means to pump blood through it.  
>> I might point out that the modern giraffe, with its head located 
>> well above its heart, has developed a number of specializations 
>> to make this possible.
>
> No. I suspect you're being a bit naughty here. IF seismosaur had a
> neck that long and IF modern physiology can't explain it, then there 
> is something wrong with one of those concepts. 

I don't think there is any question that these creatures did have a 
neck that long.  There are many things that we have to conjecture or 
deduce about extinct species, but that isn't one of them; if you dig 
an intact skeleton out of rock, and you find a neck that long, then it 
had a neck that long.  As for modern physiology explaining it, you 
recognize that we are hampered by not having a living specimen nor any 
soft tissues to examine.  If Jurassic Park were real, I don't think it 
would take too long to determine how high a sauropod could raise its 
head, or how it accomplished this.  The presence of unanswered 
questions does not invalidate modern physiology.

> Scientists who study sauropod dinosaurs are now claiming that they
> held their heads low, because theycould not have gotten blood to their 
> brains had they held them high. 

Mind you, their brains no doubt had quite low metabolic demands 
compared to ours; the small brains of sauropods are well known.  It 
may be (pure speculation on my part) that they were only able to raise 
their heads high for brief periods.

> In "Sauropods and Gravity", Harvey B. Lillywhite of Univ. Fla., 
> Gainesville, notes: 

Can you give me the rest of the citation on this?  Is this a book or a 
journal article?  If the latter, what was the year of publication, and 
the publisher?

> Therefore, hearts of Barosaurus must have generated pressures at least 
> six times greater than those of humans and three to four times greater 
> than those of giraffes." 

Okay.  Is there reason to think that they could not have?

> humble old me writes:
>
> Ted Hodson is proposing an argument for gravity being far less in 
> prehistory than it is today.

I'm not sure about that; in your quote, he says "perceived gravity".  
It's by no means clear what he means by that.

> I would love you to read his article and 
> give your opinion - you can find it on: 
>
> http://access.digex.com/~medved/biganims.html

I don't have web access at present, but I'll hold onto this reference.

>> Easy, the wind dislodges a rock, which rolls down a hillside.  No 
>> life in that equation.
>
> Hmm. A little naughtiness creeping back in here I expect. What I meant 
> to say was that thermodynamics and quantum physics explain the how
> rather than the why, i.e. it does not explain PURPOSEFUL action.

My point is that outcomes can be constrained by things other than 
wilful intent.  All the molecules in the rock moved in the same 
direction several feet; it would have been strange if they had done 
otherwise.  Yet there was no "purpose" in this.

> What is the probability that ink would arrange itself on a page to 
> form one of Shakespear's (I'm not sure if the spelling is correct -
> but then neither was he.) sonnets. If you sit me down with a copy, a
> blank piece of paper, a biro and a jam butty - then it is a dead cert!

I'm afraid you're repeating your previous mistake (bridge hands and 
probability).  Suppose we threw ink at a page.  But suppose we could 
only throw it in the shape of pre-formed letters, and they had to fall 
in even lines.  And suppose that letters had to follow each other 
according to English letter frequencies and contacts. We'd get 
something that *looked* like English but made no sense.  Now, suppose 
every time we got a string of text that looked like nonsesne, we threw 
the page away and started over.  The odds of getting Shakespeare's 
sonnet again are virtually nil, but eventually, we'd wind up with 
*something* that made sense.  And, if we start with a *short* string 
that makes sense, and are only allowed to add to it bits that still 
make sense...

> I fink I'd better read some more of them there scientifikal books!

Welcome to the Knowledge Explosion.  If you restrict yourself to just 
one narrow field, you have trouble reading all the relevant 
literature.  Most of us will settle for a broader, if shallower, 
knowledge, but even there, you have the problem of sorting the wheat 
from the chaff.  It's tough to decide what to read, given a limited 
number of hours in the day, and some of the books on the market (say, 
from the Institute for Creation Research) would leave you more 
ignorant than when you started.

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