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Using a Comparative Species Approach to Investigate the Neurobiology of Paternal Responses

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The development of male-oriented behavior in rams.

Charles E Roselli¹, Radhika C Reddy, Katherine R Kaufman

¹Department of Physiology & Pharmacology, Oregon Health & Science University, Portland, OR 97239, United States. rosellic@ohsu.edu

Frontiers in Neuroendocrinology

|January 11, 2011

Summary

Sheep provide a unique model for studying same-sex sexual preferences. Research suggests prenatal development organizes neural pathways for sexual partner choice, influenced by hormones, genes, and experience.

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Area of Science:

Zoology
Neurobiology
Behavioral Science

Background:

Sheep, particularly rams, exhibit spontaneous same-sex sexual partner preferences, with up to 8% of males preferring other rams.
This phenomenon in rams offers a unique mammalian model for investigating the biological underpinnings of sexual orientation.
Understanding these preferences is crucial for broader insights into mammalian mate selection and sexual behavior.

Purpose of the Study:

To review and update the current understanding of the male-oriented ram model.
To discuss theories explaining same-sex preferences in rams.
To highlight evidence for the prenatal organization of neural substrates governing sexual partner preference.

Main Methods:

This review synthesizes existing research on male-oriented rams.
It examines various theoretical frameworks proposed to explain same-sex preferences.
Evidence supporting the role of prenatal development in organizing sexual preference pathways is discussed.

Main Results:

The male-oriented ram model is a valuable tool for studying paradoxical same-sex sexual preferences.
Compelling evidence indicates that neural substrates for sexual partner preference are organized during prenatal development.
Hormonal, genetic, and experiential factors are implicated in shaping these preferences.

Conclusions:

The sheep model provides significant insights into the biological basis of sexual partner preference.
Prenatal organization of neural substrates is a key factor in determining sexual orientation.
Future research should integrate genetic, hormonal, and experiential influences to fully understand sexual preference development.