Harvey Karten is a prof at UCSD. He's retired now, but still hangs around.
"Cortical Equivalent" Circuits in the Nonmammalian Forebrain. Suggests that nuclei in retiles/birds in DVR are equivalent to lamina in cortex.
Two steps. 1. neurons of each sensory system evolved for all vertabrates. 2. lamination of these populations occured within mammals.
The development of DVR and neocortex should thus have similar mechanisms that have been transformed through evolution. The prosomeres (the developmental zones) around the ventricular zone should then be "found in either of two configurations: (i) in birds and reptiles, reflecting the ancestral condition common to allamniotes, they contribute to the DVR... (ii) in mammals, these prosomeres are tranposed and become components of the "subventricular zones"... as areas of proliferation seperate of epndymal zone"
Radial progenitor hypothesis poses a problem: cortex is organized into columns, stemming from a single zone. Layers are secondary from this vertical migration. This clashes with idea that layers are coming from different progenitor zones.
I think what the Molnar paper will say is that the SVC does not arise from a different progenitor zone, but instead comes from IPCs originating in the same place. Things then are almost all radially distributed.
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