This is interesting! When I offered communication as a sign of
intelligence I was thinking about the famous bee dance. One bee returns to
the hive and insructs some of the others . She will tell another bee what
is of interest,where it is , how far it is from the hive, and in a way that
we can understand. We can even create a little imitation communicator and
direct the bees ourselves. They do not have a fifty thousand word
vocabulary but it works for them. Who knows the bees may de able to
understand each other better than humans understand each other.Humans think
in words most of the time, but what about the person who is deaf and dumb?
Is that person intelligent even though they cannot use words to think with?
I sounds as though you may have bit off an awful lot to chew with this
suject. If you dont mind I would like to  read your thiesis
 
 
Jerry Fries