🚀 go-pugleaf

In article <103884@netnews.upenn.edu>, rowe@pender.ee.upenn.edu (Mickey Rowe) writes:
|> >Ditto for birds and dinosaurs.  Which is, naturally, why it was the
|> >optic tecta that enlarged in that lineage.  
|> 
|> I'm not so sure about this.  Yes, the optic tecta are relatively large
|> in these lineages, but they're also relatively large in fish and
|> amphibians.

Hmm, could be.  It has been a long time since I reviewed my Comparative
Neuroanatomy.

|> Furthermore, when vision became more important for
|> mammals, it was cortex that enlarged even though our tectum (superior
|> colliculus) is still intimately involved with vision.  In cats and
|> monkeys it's hard to find cortical regions that don't respond to some
|> sort of visual stimulation...

I would argue that this was due tot he cerbral cortex already being dominant
in mammals, and thus being the prefered location for new functionality.
[Or at least so I would speculate].

|> >Though the upper diencephalon (the optic and auditory tecta)
|> 
|> Sorry to pick nits, but you mean mesencephalon.  Diencephalon refers
|> to thalamic structures.

Oops, you're right!  Got my brain regions off by one!
[Well, actually the diencephalon *also* includes the hypothalamus].

|> 
|> P.S.  Stan there's a person over in k12.ed.science who works as an
|> illustrator of paleo-animals and plants.  She (or he, the first name
|> is Dana) is currently writing a paper about _Allosaurus atrox_ and is
|> soliciting opinions as to whether or not it could grasp with its
|> hands.  E-mail me if you'd like me to send you a copy of her article
|> (the posted one, not the one she's publishing).

Sounds like an interesting article, but I doubt I am really qualified to make
such a judgement for a formal paper.
[My comparative anatomy is rather stale - I do not use it enough].

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Stanley.Friesen@ElSegundoCA.ncr.com