Gibbons possess the first nine traditional transmission, and duality of patterning ).
2.
Additionally, traditional transmission, and duality of patterning are key to human language.
3.
This is often called duality of patterning.
4.
This duality of patterning of language is one of the few facts of language which most schools of linguistics can agree on.
5.
Look at article Charles Hockett and you'll see a list of characteristics possessed by all human languages, and many of the most important ones ( displacement, productivity, duality of patterning ) are not characteristic of animal alarm calls.