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Re: Attention Mickey!



Back into the frays...  Can't we all just get along? (sorry)

Jon Roudebush writes:

>     I implore you to do something about this behavior.  This list is
> about discussing verterbrate palaeontology not bashing other peoples
> beliefs!

Skip over this paragraph if you don't care about list administrivia.
Otherwise: as it is, I have little more power than anybody else on the
list to change the behavior and/or thoughts of its participants.  I
could change that by making the list moderated, but the last time I
asked if people wanted that change, only one person responded.  I'd
still rather not go that route, but given some of the things that have
happened here recently -- particularly the two complaints from a
confused individual who claimed not to know why he was receiving mail
from the list -- I'm sympathetic to calls for moderation.  Tom, can I
count a new yes vote from you now (vote only with one hand... hands
and feet together don't give you four times the clout no matter how
many toes you have :-)

Now for some substance (or something that will hopefully pass as such
:-)  It seems that a lot of furor has arisen since Roger Stephenson
(aka "lightwaves") wrote:

  An idea I call "genetic memory" has been rolling around my head for
  some time now. I don't know if I read it somewhere or what. It goes
  like this: Every generation passes on its genes. The more complex
  the lifeform, the more genetic information is passed on. When an
  successful individual lifeform reproduces with another successful
  individual both contribute genes that was the essence of them. The
  offspring of these may have 'talents' or 'skills' or 'instinctive
  behavior' that better serve them to survive. Is it not possible that
  these genes carry more than the physical attributes?

While the specific example that Roger used (his ability to make
arrowheads) may not be terribly amenable to the sort of explanation
proffered above, I don't think there's anything even remotely
controversial in the suggestions made in the paragraph I just quoted.
Certainly there is a genetic basis for behavior.  There's plenty of
room to argue about specifics, but you'll be hard pressed to find a
psychologist that thinks even of humans as tabula rasas upon which
environment writes anything it wants.  Just coincidentally, the
speaker at last monday's weekly Penn psych department colloquium gave
a talk entitled:

  Evolutionary Memories, Emotional Processing, and the Emotional
  Disorders.

The speaker, Sue Mineka, is at Northwestern University if you want to
track down any of her papers (how you'll get them is left as an
excercise for the reader :-) In her research Sue has purported to show
that it is much easier to train rhesus macaques to fear snakes than it
is to get them to fear other objects such as artificial flowers.  The
goal of her research is to try to understand why humans have phobias
to particular types of objects -- her claim is that many people fear
snakes because it was adaptive for our ancestors to fear them.
However, she went to great pains to stress that she is not talking
about an instinct, only a genetic predisposition for learning a
particular association.  Captive reared macaques do not fear snakes
prior to experience.  She surprised me with data indicating that you
can train a macaque to fear snakes merely by showing it videotapes of
other macaques acting afraid of snakes (both real and plastic).  I'll
ramble more if there's interest, but for now suffice it to say that
research into areas such as this are being done with no apparent
racial motivation or bias.  I'm not saying that I fully endorse the
arguments that, for example, humans are predisposed to fear snakes and
spiders, but the suggestion that we might have such predispositions
isn't exactly out of the mainstream.  And it's nothing to get hot and
bothered about, IMHO.

On the other hand, we could probably do with a little more clarity in
our definitions:

  Of the hundreds of 'races' of dogs they are still all dogs, and
  belong to the same species. Labrador retrievers have a genetic
  memory to retrieve, and ones of good blood lines are born knowing
  how to fetch, as was mine. There is no way in hell this talent is
  instinctual,

If your dog was "born knowing how to fetch", then the talent was an
instinct pretty much by definition.

Getting back to dinosaurs, I'm not sure that we can make any
particularly compelling arguments based on evolutionary memories in
contemporary animals.  Inferring dinosaur social structures based on
those of birds and crocodiles would seem to be hampered by the fact
that there is so much diversity in the behaviors exhibited by modern
forms.  How could you tell which behaviors are "ancient"?  I'm not
saying it's impossible to say anything about the subject, but I don't
think it would be too fruitful to dwell on it just yet.

-- 
Mickey Rowe     (rowe@lepomis.psych.upenn.edu)