In article <2p6msn$ohk at portal.gmu.edu>,
HARRY R. ERWIN <herwin at mason1.gmu.edu> wrote:
>Has anyone considered how neocortex evolved? I've heard that it probably
>came from paleocortex, but paleocortex is characterized by afferent
>sensory input arriving at Layer 1, while neocortex receives its input
>via the thalamus in layer 4. The pyramidal cells appear to be organized
>similarly in both, but neocortex has 6 layers while paleo has 3. If neo
>came from paleo, how did it lose its layer 1 inputs? Has anyone tried to
>do a cladistic analysis of the tetrapod brain????
I think the overall answer is that neo didn't come from paleo. A paper
that might help out is:
Butler, A.B (1994) The evolution of the dorsal pallium in the telencephalon
of amniotes: cladistic analysis and a new hypothesis. Brain Res. Reviews,
19: 66-101.
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