This work is part of a project in the quest of the origin of speech. From classical bony landmarks of the head and jaw used in anthropology, and using a generic model of the vocal tract, we applied the prediction of geometric limits of the vocal tract for modern man to fossils covering a period from 10 ka until 2 Ma (Paleolithic period). We conclude that all the reconstituted vocal tracts could produce the same variety of speech sounds that can produced by modern humans. However, we do not know to what extent ancient humans mastered the control skills needed to produce speech.