untermensche
Contributor
I gotta tell you that I've spent a lot of time, almost 50 years, attempting to divine rules of evolution, one cell detect, two cells move, etc. Very early on it became apparent to me that communication was a prime feature in evolution. If one solution resulted in better communication relative to whatever aspect was being driven it survived. Now I go pretty far with communication I admit. But it is one of those well defined regularities we've been talking about.
You drift into abstraction immediately.
Sure, one can label the excretion of serotonin by one cell and the uptake of that serotonin by another as "communication". We can abstract.
But it will tell us nothing about language.