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Re: EQ (was RE: Tyrannosaur age-population distributions)



An additional problem is that the brains of all vertebrates are covered
by a protective spongy sheath of variable thicknesses.  In animals with a
thin sheath, the brain's convolutions sometimes leave their imprint on
the inside of the skull bones. In other animals (such as crocs) this
sheath is thick, and the brain doesn't leave as clear an imprint as
scientists would want.  According to Horner, this also appears to be the
case with _T. rex_.

When computing brain volume, the volume occupied by this sheath needs to
be taken into account (in fossil animals, it needs to be estimated), and
then subtracted from the total volume of the endocast.

<pb>
--
"To an alien viewing Earth from orbit, it may not be obvious that there
is intelligent life on the planet, but it would be obvious that there are
engineers down there." - George Nelson, former U.S. astronaut.




On Tue, 18 Jul 2006 17:19:43 -0700 (PDT) "Jaime A. Headden"
<qilongia@yahoo.com> writes:
> David Marjanovic (david.marjanovic@gmx.at) wrote:
> 
> <The complexity of the foldings is directly proportional to brain 
> and body 
> size.>
> 
>   Or inversely. Consider: in humans, women's brains are on average 
> larger
> relative to body size than men's brains, but in comparison, men's 
> brains are
> more densely packed with neurons. Now, if we are considering the 
> convolutions,
> relative to cortex folding, then this is really nearly impossible to 
> tell in
> most fossil animals.
> 
>   Cheers,
> 
> Jaime A. Headden
> http://bitestuff.blogspot.com/
> 
> "Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)
> 
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