: Aye, but because our "lab-cousins" are capable
: of grasping complex languages we teach them, then it
: is only chance that they have not yet stumbled onto
: the invention of their own complex languages. Sure,
: they are not AS advanced as us, and thus couldn't
: develop the same level of complexity, but given time
: and chance they could develop some complexity
: comparable (though likely not equal) to humans.
it is not chance that apes have not developed a language. or perhaps i should say, it is chance, since humans evolved from apes and humans have language. the point is that there are physical brain differences between humans and apes that explain differences in language ability.
for evolutionary reasons, human brains have evolved to have a structure whereby we are not just capable of learning language, but in some important sense THIRSTY for it. what's amazing about human language is not that it is teachable to young human beings, but that young human beings can't AVOID learning it. symbols have to be taught to apes through stimulus and response (and perhaps other means), but just try to keep a human child from learning the language spoken around it!
sure, there is some moderate education done, but so much language ability we don't really have the slightest idea how to teach. there is something in our brains that's actively looking for a language because of the way the brain is structured. this is something apes, for whatever reason, don't have. there are rules already built in to human brains that are not, and perhaps can't be, taught. otherwise, there's no way millions of people could learn the same language from such small and different samplings. we each get very different samples of the english language but ended up with the same one. this is amazing. (this is noam chomsky's 'poverty of the stimulus' argument.)
by the way, when i'm talking about a language, i'm not talking about the vocabulary--which could hardly be learned without a degree of stimulus and response--but the grammar. and although we have 'grammar school' and grammar textbooks, that kind of grammar is surface grammar--ways we've gotten used to hearing expressions. the underlying grammar of english is something english-speakers don't get wrong. the fact that nobody makes certain kinds of grammatical errors one would ordinarily expect means that something inside is keeping us from making those errors--things in our brain, that humans have for the purpose of learning a language. and why do we have a language? it benefited our ancestors somehow in our evolutionary past.
what koko and other apes have learned to do with language is fascinating and instructive. apes are very close to us on the family tree, and undoubtedly have powerful brains. but human children are levels of magnitude more capable with language than are apes.
now--all this isn't to put down apes. apes do a great many things better than humans do. and why any other species would need a human-like language is beyond me.
