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Study Links Rat Digit Ratio to Sexual Behavior

7/3/2025

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Summary

Story summary

A groundbreaking study from Okayama University reveals that the length ratio of male rats' second to fourth digits (2D:4D) can predict their sexual activity and preferences. Rats with shorter second digits displayed heightened sexual vigor and a stronger attraction to female scents, highlighting the profound impact of prenatal hormones on behavior and shedding light on gender diversity and mental health.

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Story summary

A groundbreaking study from Okayama University reveals that the length ratio of male rats' second to fourth digits (2D:4D) can predict their sexual activity and preferences. Rats with shorter second digits displayed heightened sexual vigor and a stronger attraction to female scents, highlighting the profound impact of prenatal hormones on behavior and shedding light on gender diversity and mental health.