Of course my conclusions had flaws. As I stated they were to prompt input. My observations on the communicative ability/necessity of males and females was in no way intended to slight the male gender, perhaps you are a little over-sensitive to the 'feminist' thing. I based it totally on necessity being the mother of invention (sorry about the gender reference of the quote). Even the hunter/gatherers had emotions. Love, hate, frustration would have to prompt some audible reaction. Cave paintings would give some credibility to my assumption that the need for communication was an issue.