The neurobiology of sexual partner preferences in rams

Charles E. Roselli, Fred Stormshak

Research output: Contribution to journalArticlepeer-review

30 Scopus citations


The question of what causes a male animal to seek out and choose a female as opposed to another male mating partner is unresolved and remains an issue of considerable debate. The most developed biologic theory is the perinatal organizational hypothesis, which states that perinatal hormone exposure mediates sexual differentiation of the brain. Numerous animal experiments have assessed the contribution of perinatal testosterone and/or estradiol exposure to the development of a male-typical mate preference, but almost all have used hormonally manipulated animals. In contrast, variations in sexual partner preferences occur spontaneously in domestic rams, with as many as 8% of the population exhibiting a preference for same-sex mating partners (male-oriented rams). Thus, the domestic ram is an excellent experimental model to study possible links between fetal neuroendocrine programming of neural mechanisms and adult sexual partner preferences. In this review, we present an overview of sexual differentiation in relation to sexual partner preferences. We then summarize results that test the relevance of the organizational hypothesis to expression of same-sex sexual partner preferences in rams. Finally, we demonstrate that the sexual differentiation of brain and behavior in sheep does not depend critically on aromatization of testosterone to estradiol.

Original languageEnglish (US)
Pages (from-to)611-620
Number of pages10
JournalHormones and Behavior
Issue number5
StatePublished - May 2009


  • Anterior hypothalamus
  • Aromatase
  • Preoptic area
  • Rams
  • Sexual orientation
  • Sexual partner preference
  • Sexually dimorphic nucleus
  • Sheep

ASJC Scopus subject areas

  • Endocrinology
  • Endocrine and Autonomic Systems
  • Behavioral Neuroscience


Dive into the research topics of 'The neurobiology of sexual partner preferences in rams'. Together they form a unique fingerprint.

Cite this