How did we end up doing all this talking?

This morning I sat in bed reading a New Scientist article about the evolution of language.  Not only does this link in with my studying, but I've mentioned before that I'm interested in language.  According to the article, (which concentrated on spoken language rather than writtten) there are three main theories behind it, what are known as 'protolanguages' ie. systems which have some of the components of language but not all of them.

Musical: an explanation first offered by Darwin in 1871, roughly saying that to start with vocalisation in animals/birds was just to say "Hey, I'm here, and I want to mate."  Darwin reckoned that early human vocal learning more closely resembled song than speech. which later started taking on more meanings.

Gestural:  ie. communication was originally by gesture rather than speech. This is supported by the fact apes and chimps can be taught gestures and some sign language, but no-one has managed to teach them to speak.  One suggestion is that gestures originally referred to whole thoughts or events, rather than individual things or actions.   I can just imagine the gestures used to convey "So, fancy coming out to watch me hunt, then back to my place for some rumpy pumpy?"   The various possiblities of why this would develop into speech include the need to communicate in darkness, or with their hands full of spear heads perhaps?

Lexical: ie. the use of individual words before this developed into forming complex sentences.  This parallels with how children initially learn, gradually building up the number of words they can string together to make sense.  Well, they make sense to their parents anyway.

Another section of the article explained the physical differences in larynx position in different animals, and how this affects the ability to speak. However, it's not that simple, since lions and tigers have low larynxes like we do, yet they cannot speak (I'm excluding The Lion King here, ok?).   So it really comes down to how the brain is wired up and how that evolved over time.

I ended up sitting in bed, with a finger held lightly either side of my larynx (where the Adam's Apple is) and discovering that when I spoke I could feel the vibrations; and if I made different sounds, at different high or low tones, I could feel it moving up and down etc.   I daresay this is obvious, but personally I have gone 44.5 years without ever trying it.  If the neighbours were listening at the bedroom wall they must have wondered what the hell was going on!