[Biology of human speech communication].

In this paper the analysis of the human acoustic communication channel is presented as a potentially bio-anthropological subject of interest. After a crude survey concerning some important aspects of speech and expressive behaviour a hypothesis is outlined saying that the verbal and the nonverbal content of the speech signal are not just transferred side by side; rather there exist close interconnections between the linguistic and the expressive structures, which is shown regarding the speech melody; the 'cultural' language code makes use of a predominantly 'non-cultural' code of vocalisations for the purpose of linguistic disambiguation and speeding up the communication process. The complementarity of these two codes, their principal independence of each other as well as their different cerebral representation contribute to the high efficiency of speech as a communication tool.