Apparently they [creoles] have a grammar all their own that is comparable to the grammar of other creoles. This is something that has interested me but that I have not had the chance to dig into very deeply.

Me too, faldage.

As I understand it, these two points have been cited as evidence that the basic structure of "language" is an inherited, genetic trait in human beings.

1) The various creole languages, though arising from entirely separately and from differing mixes of populations, have a rather large number of structures in common.
2) Also, where those structures may not match the "civilized" language of a particular country, the do match the errors that a young child will make when learning the language. For example, in English the double-negative cannot be used as an emphatic negative, but young children often use it that way -- and creole languages use it that way.

Note: the above is my recall of a highly technical book published about about 20 years ago, which I read at the time -- and which was way beyond me. I recall its title as Roots of Language but I cannot find that title. Any information on this would be greatly appreciated.