Meanwhile, have been going back over my archive of our recent discussions
on development, play, prolepsis, phylogeny, etc. And wanted to offer a few
notes on what are, for me at least, still loose ends.
Bill Barowy, August 21, raised a very interesting point by arguing that
play should not play a part, proleptic or otherwise, in the ontogeny of
species-specific behaviors (chicks flying, people talking) because the
phylogeny of these behaviors evolved 'without motive' and their
recapitulation in the individual should also not require
activity-with-motive, whether in the form of play, or any zpd learning
activity. But I'm pretty sure that while his premises are correct, the
conclusion is not.
What evolves, first of all, is the typical developmental trajectory itself
(which cannot, as our discussion got to later, be isolated from the larger
ecology's role). A genetic shift creates a potential for new behavior, a
developing organism with the mutation then needs a supportive environment
in which the behavior gets done the first time, often as part of some
motivated activity (in a very broad sense), but with the specifically new
feature entrained by that activity, but its genetic possibility NOT a
result of the activity-motive of course. That the first time. Perhaps many
first times for different organisms so endowed (mutations tend to re-occur,
they are not absolutely random in origin or nature). The gene pattern gets
passed on, whether there is adaptive advantage or not. The supportive
environment does not always occur, the behavior does not always occur. But
let's say that the enviro support is reliably present, the genetic
potential gets phenotypically expressed in the behavior frequently, and the
behavior confers advantage (in both the phenotypic sense and the
gene-passing sense; you live, you eat, you make more babies than the next
girl).
Now in this picture the typical developmental trajectory of the population
begins to shift, from one without the gene and the behavior (where the
presence of the supportive enviro was irrelevant phylogenetically), to one
with the gene and the behavior and where the presence of the supportive
environment (here participation in motivated social activity of a certain
type) is epigenetically integral to the successful expression of the gene
potential, and so to its maintenance in the population. Development, as
gene expression, creates a link between the unmotivated potential
consequences of genetic changes and the (potentially motivated)
environmental processes in which a particular consequence becomes expressed
so as to allow the possibility of phenotypic selection and phylogenetic
change. This more complex epigenetic model, where evolution and development
are tightly interdependent, and their time-scale separation NOT the barrier
it is usually assumed to be, unifies not only ontogeny and phylogeny (as it
must), but also organism genetics and ecological affordances, unmotivated
genetic potentialities and potentially motivated ecological pathways to
gene expressions.
No doubt this view has consequences for our view of learning, but that's
another matter.
JAY.
PS. Having now read further to the postings from David Dirlam and Linnda
Capporael I am pleased by the apparent convergence with my point here and
looking forward to following up on these matters.
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JAY L. LEMKE
CITY UNIVERSITY OF NEW YORK
JLLBC who-is-at CUNYVM.CUNY.EDU
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