Language

Why have humans been able to develop language?  Even "primitive" cultures still have language.  Yet somehow no other creature has been able to get past basic signals.  Even monkeys, gorillas, dolphins, dogs, cats, and birds don't have a language.  Sure they can "get by" just fine, but they could express a lot more with an equivelant to words and sentences. 

Humans that are isolated from other humans actually lose brain function and language ability, while a stimulated brain grows the language areas of the brain as the human learns early.  An "animal language" taught at baby age should be able to work, as long as the animal can repeat different noises.  It doesn't have to sound human.  Bears would have different noises that mean something, like Wookies.    

I think Noam Chomsky is full of it.

If by language you mean attaching meaning to arbitrary symbols (symbols in any form) in order to communicate, then I think it's wrong to assume that animals do not have language. Most animals, even squirrels, communicate in this means. (A bunch of scienetist have codified squirrel squeaks and grants that follow the basic 'universal grammar' rules Noam Chomsky pionnered)

If you are wondering why the language humans use is so much more complex and can communicate so much more semantics, then I would agree with most above statements in that it is an accidental Darwinian feature. Using the language we used helped us survive better thus promoting those genetics (I.E Natural Selection).
Why we can't teach, say, a Dog to speak a human-type language is probably because of anatomical-physical limitations in their brain structure, as well as something like their eye-sight.

Again, I think animals use language but not human-like language because of anatomical-physical limitations. You could teach Koko or some other high-ape sign language, but the pace is painfully slow and they do reach a limit. Maybe Gorillas could have evolved to employ a more semantic-rich language. I don't see that happening though.