The nature of communication

I have always been fascinated by the very nature of communication.  I personally think that language was invented as means to pass knowledge from one person to another with the need for personal experience.  Take for instance a pair of early Homo sapiens eating, we will call them Jack and John for simplicity's sake.  Jack eats some berries (goodberries) and finds them to be sweet and refreshing.  John eats some different berries (badberries) and finds them to be bitter and caustic and, ultimately, ends up with an upset stomach.  

Now, let's say the next day Jack and John go to the same area to get some berries for a snack (I know that studies and evidence suggests that in primitive societies, men hunt while women and children gather, but let's not worry about that in this post...).  Jack reaches for some badberries.  If John could tell Jack about his experience with the badberries, Jack would be very grateful and would gain a lot of utility from this knowledge.  Similarly, John would be appreciative of Jack telling him about the goodberries.  So at some point, early Homo sapiens must have realized that sharing knowledge could be of very high utility and they, consequently, invented language.  (On that note, here is a very interesting article about human evolution and language)

By gaining this ability to share information without the need for personal experience, humans have been able to learn very quickly... I would argue that we've been able to learn quicker than other animals have been.  Think about it.  If other animals didn't learn at all, then wouldn't many more birds and squirrels die by running in front of/flying into cars?  Clearly they have learned that cars are lethal to them.  Am I suggesting something like what is suggested in "Bee Movie"?  Yes, but not to that extent (obviously).  The best argument I could come up with other than learning is that animals view human inventions, such as cars, as predators.  The inherent problem with that argument, though, is that birds fly at cars and then turn skyward at the last moment to avoid being killed.  If they viewed cars as predators, why in the world would they fly toward cars instead of away from them?  I think the only logical explanation (and I am open to other arguments, so if you disagree, please leave a comment with your argument) is that other animals also learn.  How?  Language.  

Just like with humans, birds and squirrels have figured out a way to tell their young something specific (that cars can kill them) without requiring them to experience that thing.  So here is the problem... what caused humans to learn quicker than other animals through language?  I think (but am not sure) that current theory suggests it is due to Homo sapiens's brain size and utilization.  

So assuming (which might be a big assumption) that this is a somewhat accurate description of why language was developed, what does this mean going forward?  Well, if you consider that the math children currently learn in grade school (even in the US which ranks terribly in terms of mathematical ability of school children) is the same kind of math that their grandparents or maybe even their parents didn't learn until college, it doesn't seem to be too great a leap of logic to say that humans will continue to become increasingly intelligent.  Other than that, I have no clue about how evolution and increased passage of knowledge will affect humans...  I am interested in what you have to say though, so please let me know and maybe we can help advance our species.

(I realize that I have not even mentioned the arbitrary nature of words, but that will be discussed in another post)