Development of functional sex differences in the larynx of Xenopus laevis

Martha L. Tobias, Melanie L. Marin, Darcy B. Kelley

Research output: Contribution to journalArticlepeer-review

41 Scopus citations


Three laryngeal properties associated with the production of masculine song-laryngeal muscle tension, fiber twitch type, and fiber recruitment-are markedly sexually dimorphic in adult Xenopus laevis frogs. To elucidate the pattern of sexual differentiation, tension and fiber recruitment in male and female larynges and fiber twitch type in male larynges were examined throughout postmetamorphic development. Masculinization of male laryngeal properties begins early in postmetamorphic development and continues until adulthood. In contrast, tension and fiber recruitment in females do not change after the end of metamorphosis. Laryngeal muscle tension and fiber type are gradually and progressively masculinized; the temporal pattern of masculinization is very similar for these properties. Fiber recruitment, on the other hand, appears to masculinize in a stepwise manner. Masculinization of all three properties is highly correlated with larynx weight in males. We have used this relation to divide postmetamorphic development into seven stages associated with key events in sexual differentiation. This staging scheme provides an important experimental tool for studying the hormonal regulation of sexual differentiation, the subject of the accompanying paper.

Original languageEnglish
Pages (from-to)251-259
Number of pages9
JournalDevelopmental Biology
Issue number1
StatePublished - Sep 1991
Externally publishedYes


Dive into the research topics of 'Development of functional sex differences in the larynx of Xenopus laevis'. Together they form a unique fingerprint.

Cite this