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Changing the Evolutionary Minded?

I found myself tied a bit to the theme of last week’s blog when my attention was brought to a very recent article in PLoS Biology called Darwin in Mind: New Opportunities for Evolutionary Psychology.  In it a team of biologists, psychologists and philosophers from the Netherlands, the United States and Scotland, suggest that the 30 year old interpretation of the evolution of the mind put forward by evolutionary psychologists can perhaps be remodeled now by drawing on recent work in related disciplines (like neuroscience, cognitive science, genetics, and developmental psychology).  The old view is characterized by a few beliefs:  that human behavior is unlikely to be adaptive in modern environments, that human cognition is task-specific, and that there is a universal human nature.

This perspective presumes that psychological mechanisms have evolved in response to the features of an ancestral environment (like the African Pleistocene Savanna) and that gene complexes cannot respond quickly to natural selection, creating an adaptive lag.  Among other things, the authors make the following observation:

Recent trends in developmental psychology and neuroscience have instead stressed the malleability of the human brain, emphasizing how experience tunes and regulates synaptic connectivity, neural circuitry and gene expression in the brain, leading to remarkable plasticity in the brain’s structural and functional organization. Neuroscientists have been aware since the 1980s that the human brain has too much architectural complexity for it to be plausible that genes specify its wiring in detail; therefore, developmental processes carry much of the burden of establishing neural connections.

I found ‘A Review of the Evolutionary Psychology Debates’ from 1999.  It was written by Melanie Mitchell at the Santa Fe Institute.  What I realized after reading it was how tricky it was to apply biological ideas to psychological theories.  Her paper quotes many of the authors of evolutionary psychology and I think this particular statement points to the problem:

to understand the relationship between biology and culture one must first understand the architecture of our evolved psychology…..

It is very difficult to keep the opinions and prejudices of our current culture out of an analysis of our  ‘evolved psychology.’ But we do want to understand the relationship between biology and culture.  And I think this happens only when we are willing to give the body its due, when we are willing to imagine that the way the body may direct itself is far from clear to us.  One of the observations Mitchell makes from the literature is this one (which I like very much):

Pinker asserts that “most of our evolution took place” on the African savanna.  By “our evolution” he means that of our most human-like ancestors—those with brains similar to ours. But, as Ahouse and Berwick point out, it would be equally true to say that “over 99 percent of our evolutionary history was spent in (and most of our genes arose in) a warm, salty sea.”  Our sea ancestors also had nervous systems, ancestral to our own. Would it not be plausible to speculate that some of the structures important to human psychology arose, at least in part, during that time and were originally adapted for those conditions? And could this have had as much of an effect on their ultimate structure and function as the time spent in the Pleistocene? It is hard to say for sure.

This is exactly the right correction to make on the evolutionary psychology perspective.  There is no easy way to understand how an ancient cell’s signaling processes developed into the nervous system with which we breathe, find nourishment, move and imagine.  And now I’ve said the word that leads me to mathematics – imagine.  I think that we have not been able to really refresh the way we see ourselves for a very long time.  Part of what motivates this blog is the exploration of how the effectiveness and conceptual reach of mathematics can bring new insight to understanding how the body does what it does.  Abstraction is the key in mathematics and current work in both cognitive science and neuroscience looks at how primitive an abstraction can be in learning and even in vision.  Neuroscientists have been able to determine that, in vision, specialized cells respond preferentially to straight lines at a particular angle.  About this, the visual theorist Semir Zeki says, “the cell abstracts verticality without being concerned with what is vertical.” Cognitive scientists like Joshua Tenenbaum have observed how quickly an abstraction can be formed (in both children and adults) and they now consider that we have an innate stock of abstract concepts.  The important point is that in both vision and learning the abstraction initiates the building of structure.  These abstractions are not thoughtful in the usual sense but inherent, natural and automatic.  Mathematics, then, may reflect something very basic to human life, something grounded in the very way we exist.

 

 

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