Sex differences in f0

In the last session we discussed whether men have lower voices than women in terms of f0. But why is this interesting? Understanding such things plus some other details can help to explain certain human behaviour at least in certain communcative situations. On top of this scientific interest, there might be personal interests. For example, I might be a singer and have always wondered how single singers can drown out a whole orchestra without any amplifier.

In any case, during our discussion I pretended to be sceptic and asked for an explanation. You suggested that men have longer vocal cords than women and, therefore, lower voices. However, besides your personal convictions, nobody knew of empirical evidence for this claim. Of course, we can't stick out our tongues (very widely) and measure the length of our vocal cords with a fancy pink plastic ruler. What we can do, is check if someone else did something similar, and surprisingly Lieberman and Blumstein (1988; p. 36) did and report that "[t]he longer vocal cords of adult males, which are a consequences of secondary sexual dimorphism in Homo sapiens, yield a lower range of fundamental frequencies."

In addition, we talked about the length of the vocal tract and whether it affects f0. In fact, the longer the vocal tract, the lower are the formant frequencies (Fitch, 2000), and f0 is part of the formant frequencies. Fitch (2000) also states that vocal tract length is correlated positively with body size. From there it's only a small step to sex differences. Men tend to be larger than women, therefore, they will have a longer vocal tract and a lower voice (f0) as we suspected in the beginning. Moreover, now we know some empirical evidence for our claim.

Oh, and then we discussed how to present arguments for a research question...


Lieberman P, & Blumstein, S. (1988). Speech Physiology, Speech Perception, and Acoustic Phonetics. Cambridge University Press.

Fitch, W. T. (2000). The evolution of speech: A comparative review. Trend in Cognitive Sciences, 4, 258-267.