To explore this, researchers at the University of California, Davis, and the University of Texas at Dallas developed a database of speech samples from children ages 5 to 18 to explore two questions: What types of changes occur in children’s voices as they become adults, and how do listeners adjust to the enormous variability in acoustic patterns across speakers?
Listeners assess a speaker’s gender, age, height, and other physical characteristics based primarily on the speaker’s voice pitch and on the resonance (formant frequencies) of their voice.
“Resonance is related to speaker height — think violin versus cello — and is a reliable indicator of overall body size,” said Santiago Barreda, from the University of California, Davis.
Apart from these basic cues, there are other more subtle cues related to behavior and the way a person ‘chooses’ to speak, rather than strictly depending on the speaker’s anatomy.
Listeners with both syllables and sentences from different speakers, gender identification improved for sentences. They said this supports the stylistic elements of speech that highlight gender differences and come across better in sentences.
They made two other important findings. First, listeners can reliably identify the gender of individual children as young as 5.
Second, they found identification of the gender of speakers must take place jointly with the identification of age and likely physical size.
Based on these findings, researchers concluded that when the gender of individual children can be readily identified, it is because of differences in their behavior, in their manner of speaking, rather than because of their anatomy.
In other words, gender information in speech can be largely based on performance rather than on physical differences between male and female speakers.
If gendered speech followed necessarily from speaker anatomy, there would be no basis to reliably identify the gender of little girls and boys.
The performative nature of gender has long been argued on theoretical grounds, and these experimental results support this perspective.