Voice change as a new measure of male pubertal timing: A study among Bolivian adolescents

Abstract

Background: Age at menarche is often used to measure maturational tempo in girls. Unfortunately, no parallel marker exists for boys. It is suggested that voice change has a number of advantages as a marker of the timing and degree of male pubertal development.

Aim: Traditional auxological methods are applied to voice change in order to compare differential development both between (males vs females; Tsimane vs North American; better vs worse condition) and within (voice vs height; fundamental frequency vs formant structure) populations.

Subjects and methods: Fundamental and formant frequencies, as well as height and weight, were measured for 172 Tsimane males and females, aged 8–23. Participants were assigned to ‘better’ or ‘worse’ condition based on a median split of height-for-age and weight-for-age z-scores.

Results: Results support dramatic vocal changes in males. Peak voice change among Tsimane male adolescents occurs∼1 year later than in an age-matched North American sample. Achieved adult male voices are also higher in the Tsimane. Tsimane males in worse condition experience voice change more than 1 year later than Tsimane males in better condition.

Conclusion: Voice change has a number of attractive features as a marker of male pubertal timing including its methodological and technical simplicity as well as its social salience to group members.

Keywords::

• Puberty
• adolescence
• voice
• fundamental frequency
• formants
• formant dispersion
• peak height velocity
• pitch

Acknowledgements

The authors would like to gratefully acknowledge the contributions of David Puts. We also thank Tsimane participants and their families, as well as our research assistant, Sofonio Maito Tayo, and his wife, Beronica Canchi Apo, and Bartek Plichta for his help selecting field-appropriate recording equipment and the Tsimane Health and Life History researchers and staff for general support and assistance.

Declaration of interest : This work was supported by a Wenner-Gren dissertation fieldwork grant. The Tsimane Health and Life History project is supported by grants from NSF (BCS-0136761) and NIH/NIA (R01AG024119-01, R56AG024119-06, R01AG024119-07). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.