I've been reading "What's in the Brain That Ink May Character?", by Warren S. McColloch, 1964. He
mentions the idea of "half-centers" - more commonly known today as behavioral mechanisms based upon
reflex arcs.
This got me to wondering how it might have been in early evoluton that reflex mechanisms evolved.
Gould talks about the ideas of redundancy and re-use as ways in which existing structures can
transform in new organisms to perform different functions. So, what might have been the genesis for
reflex arcs [and then the half-centers]? Differentiation of existing linear muscle groups? Or might
muscle groups have always existed in opposite pairings? It would seem to make sense that first there
was the basic muscle group, and then there were the 2 muscle groups working in opposition. ??????
Quoted message said:From McColloch's paper:
"Evolution has provided us with reflexive arcs organized for the most part by what are called 'half-
centers', whose activities may alternate, as in breathing or walking, or synchronize, as in jumping.
These are then programmed for more complicated sequences, and all of these are marshaled into a few
general modes of behavior of the whole man ..."
thanks for any feedback,
- dan michaels
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