The scientific study of speech production has been undertaken within a variety of disciplines, including linguistics, physiology, physical acoustics, and psychology, among others. In recent years, it has become possible to combine the knowledge accumulated within these separate disciplines to gain more insight into the nature of this complex human activity. Here, we apply an interdisciplinary focus to one of the most widely discussed and poorly under stood aspects of the speech signal. This study of fundamental voice frequency involves a mixture of linguistics, physical acoustics, and...