IANAL (where L = Linguist), but I never considered Chomsky's universal grammar as more than an interesting hypothesis. I realize it became a cornerstone of a view of humanity for some. My point was that it's not really necessary. You know, recursive structures are what separate humans from animals... Hmmm.

I suggest that symbolic language is human-specific, you reply (without refs) that "it is considered" monkeys are capable of using symbols. We could probably argue about that, but I don't see the point. In your example, the monkey has to be laboriously taught. It's the spontaneous generation of structured symbolic language that is human. (The Pirahas may use simpler structures, it doesn't matter).

I don't particularly care about the human/animal distinction. I'm not fighting desperately to preserve it. But I think the good old jump in the size of the neocortex produced a cognitive leap that includes structured symbolic language and cultural complexity.