I'd refine this as follows:
Genes that bias towards ease of socialization/vulnerability to "peer 
pressure" [These traits are IDENTICAL!]  [The inverse extremes are autism 
and Asperger's syndrome.]
Genes that bias towards the minimal intelligence required to communicate 
with, but no higher.
Overall, humans seem to be well-adapted on the first trait.  Example 
1960's experiments include:
[film, 10th grade]
Virtual Electroshock: Nominally to test learning by negative 
reinforcement, Really to Test the Moral Rectitude of the Administerer
=====
     just over 600 subjects
     Only 2 walked out of the experiment at any point [These two passed.]
     <15% had doubts.
=====
[Some James Dobson book aimed at vulnerable teenage men.  Source cited 
there.]
Do I believe the audience, or my senses?
     Roughly, 7 out of ten believe the audience [researcher cohorts 
guaranteed to give the WRONG answer to a simple "which line is longer?"] 
rather than their senses.
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/   Towards the conversion of data into information....
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/   Kenneth Boyd
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