Taking the "broken" out of "broken English," part 3

So, what does a language need to have in order to count as a human language, and do those varieties of English sometimes regarded as "broken," "ungrammatical," or even just "slang" have what it takes?

There are several directions one might take in answering this question. The answers will not differ, but different audiences will require somewhat different approaches or different mixtures of the approaches.

• The "Universal Grammar" approach. This assumes that the audience knows enough about linguistics to handle concepts such Principles and Parameters, Merge, Move, Projection, and so on.
  
• The "Design Features" approach.  This approach will work for both folks who have had linguistics and the unwashed, as the relevant design features (Hockett 1960) are relatively non-technical.
  
• The "Language Arts" approach.  This approach should work for almost anyone who has at least weathered the twelve years or so of "language arts" and related material usually offered in the public schools.

For this post, I will take maybe two examples from each of these approaches, in reverse order (i.e. from least to most technical).

This just about sums it all up...

...but you'll have to go below the fold to see it. Caution: not for pets or small children.

Chimp vs. human vocal tracts

I may write more about this later, but for now just examine the differences.

Later... (added on Oct 9, 2010):

Essentially, in apes the larynx is higher and the epiglottis can lock with the velum; in humans the larynx is too low for this to happen. Also, ape tongue movement is mostly in-out, while humans can move the muscle up and down as well as in-out. Furthermore, the tube through which air passes from the glottis out to the lips is gently curved in apes, but in humans it forms a right angle. Anyone who plays any kind of wind instrument knows that different shapes produce different sounds.

What all this means is that apes (and human newborns, who are similar) cannot produce sounds with the acoustic properties of adult human speech. And it's why it was such a stroke of genius to try out manually-produced sign languages on them.