intelligence & evolution

Rob Quinlan (C611417@MIZZOU1.MISSOURI.EDU)
Fri, 17 Feb 1995 14:09:56 CST

I just wanted to throw in a couple more comments on the evolution of

1. In R. Alexander's (1989) evolution of the human psyche paper (already
cited in a previous post) he introduces the concept of "ecological
dominance", which I think might be worth considering. The concept has
to do with the source of selective pressures. Basically, an ecologically
dominant species' selective pressures come from conspecifics rather
than in solving subsistence or predation problems. Competition between
groups sets up a selective pressure for cooperation within a group.
But there is another important selective pressure and that is to avoid
being the victim of a free-rider.

2. Elsewhere (in _The biology of moral systems_ and in some papers) Alexander
introduces another concept: indirect reciprocity. There are two types of
indirect reciprocity. (1) "a" does something for "b", "b" does something for
"c", and "c" does something for "a". (2) By observing the interaction of other
individuals one can get certain key information. Example: "a" observes
"b" sharing a piece of meat with "c". Later "a" observes that "c" refuses to
reciprocate with "b" by giving him/her some meat when "c" has it. So, through
indirect reciprocity "a" knows that "c" tends to be a free-rider. In the
future "a" will not bother sharing with "c", because he/she knows "c" is
unlikely to reciprocate. Therefore, "a" avoids the cost of being ripped
off by "c". IMHO this is a big part of what intelligence is and was for.
I.e., for taking advantage of opportunities for indirect reciprocity.

3. I've been trying to learn how to flint knap for a little while now.
I've had modest success making hand axes, spear points, and arrowheads.
>From this little bit of experimentation it seems to me that the psycho-
logical mechanisms for tool manufacture and reciprocity are the same.
They both involve fairly straight forward forms of conditioning as the
basic psychological thingie. (Admittedly both are much more complex, but
were talking basics here.) Anyway, in reciprocity to one gives something --
an action that is reinforced by the return of an item or service of
roughly equal value. In flint knapping you bang stones together resulting
in a flake. Good technique is reinforced by the production of useful
flakes. The problem is that operant condition is present in really
simple organisms so is not sufficient to explain human intelligence.
What we need here to better understand both phenomena is some understanding
of goal oriented behavior. The goal of banging rocks together is to
get a good flake, which is used in the service of other goals. I don't
really know where to go from here, except to say that I find J. Barkow's
_Darwin, Sex and Status_ (one of my favorite books) helpful in
understanding the organization of goals, subgoals etc. I don't really
have time to go into this in detail. You all could help me out by
taking up the discussion of the evolution of goal oriented behavior.

4. I have a question for people who know more about comparative anatomy
than I do (I don't know much at all). It seems to me that humans are
unique in the outwardly observable characteristics of their eyes.
That is, they have a much larger white part than other species. Is this
true? I'd like to argue that this is an adaptation for indirect
reciprocity -- as it allows one to assess the attention of others. It's
fairly easy for humans to tell the direction of someone else's gaze
and it's quite common to for humans to use their gaze communicatively.
Consider a crowded, loud pick-up bar -- tons of communication goes on
simply in the direction of a gaze. At this point I'll have to apologize
for getting Desmond Morrisesque, but I don't know of any literature on
the subject. Eibl-Eibesfeldt (_Human ethology_) talks a bit about eyes,
but says nothing about the functional significance of the whites. I
also know of a little research on facial expressions, but as far as I
gather none of it addresses this particular question.

I wish I had more time to tie these things together a bit better, but
for now I'll just have to hope you all have an idea where I'm going with
this based on previous postings. As usual, sorry for the length.

Rob Quinlan