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Re: dinosaur brains



>And it seems there is a bit of misunderstanding between us. The Troodon 
>probably could not evolve to an intelligent species, that's right. I
>tried to say that another branch of dinosaurs relatives of the
>Troodontidae that we DOES
>NOT KNOW (since we do know SOMETHING about a few percent of the
>dinosaurs) may be evolved to an intelligent species.

     You could put forth the same specualtion for any moderate to large
sized animal exisiting at the time of any mass extinction in geologic
history.  You would have better odds speculating about a sapient species
causing mass extinctions at some time during the Cenozoic, when you had
mammals with larger brains with more cerebral convolutions then any
dinosaur that lived.  

> I do not know what was in the skull of a Troodon but I am afraid you also 
> don't know too much about it. The development of the cerebral
> hemispheres are important in the human evolution but who knows how
> another intelligent species would evolve?

      The braincase of an animal can provide a great deal of information
about the anatomy and relative sizes of different parts of the brain.
Phil Currie in particular has written papers on the anatomy of the
troodontid brain case that are well beyond my knowledge of cranial anatomy
and function to understand.
     As far as troodontids or troodontid relatives doing soemthing
radically differerent with thier brains that involves using something
other then thier cerebral hemispheres to "think" (spinal cord?  olfactory
bulbs?  what did you have in mind?) keep in mind that the general
functions are generally consistent for terrestrial vertebrates.  The
different parts of the brain have about the same functions in extant birds
and reptiles, animals with a bigger phylogenetic gap between them then
either have between themselves and dinosaurs.    
     Paleontology requires a careful balance between assigning too
much certainty to speculation and overly disregarding our knowledge
and understanding of modern animals to say "fossil animals are
extinct; they might have been made of helium or thought with thier
olfactory bulbs for all we know".  Both the falling T-rex debate and
this troodntid brain discussion seem to me to be treading a little
too heavily toward the latter.  Yes, there are always possibilities, and
the finest details will probably never be nailed down.  However, if
we are just going to completely shuck such highly suggestive data as basic
physics, knowledge of the capabilities and limits of tissues in modern
animals, andthe general consistency of brain design and function in modern 
animals, then we might as well label paleontology as a completely
fruitless endevour and go do something else with our time.

LN Jeff
O-