Female voices are harder to lower than male voices are to raise

Evidence

It is harder for a female to imitate a man’s voice than the reverse. A man can raise the pitch of his vocal fold oscillations into the female range, but a female may have a lower limit that is above that needed to imitate a male. Both sexes have the challenge of adjusting the formants. — Eric J. Heller, Why You Hear What You Hear- An…, 1718

Categorization

• QUESTION: Why is there an asymmetry in pitch manipulation limits between the sexes by default — is it purely vocal-fold length range, and could training change it?
• XREF: connects to: Embodied history of being desired audibly shapes a woman’s voice.