Exposure to naturally circulating androgens during foetal life incurs direct reproductive costs in female spotted hyenas, but is prerequisite for male mating.

Published

Journal Article

Among all extant mammals, only the female spotted hyena (Crocuta crocuta) mates and gives birth through the tip of a peniform clitoris. Clitoral morphology is modulated by foetal exposure to endogenous, maternal androgens. First births through this organ are prolonged and remarkably difficult, often causing death in neonates. Additionally, mating poses a mechanical challenge for males, as they must reach an anterior position on the female's abdomen and then achieve entry at the site of the retracted clitoris. Here, we report that interfering with the actions of androgens prenatally permanently modifies hyena urogenital anatomy, facilitating subsequent parturition in nulliparous females who, thereby, produce live cubs. By contrast, comparable, permanent anatomical changes in males probably preclude reproduction, as exposure to prenatal anti-androgens produces a penis that is too short and has the wrong shape necessary for insertion during copulation. These data demonstrate that the reproductive costs of clitoral delivery result from exposure of the female foetus to naturally circulating androgens. Moreover, the same androgens that render an extremely unusual and laborious process even more reproductively costly in the female are apparently essential to the male's physical ability to reproduce with a normally masculinized female.

Full Text

Duke Authors

Cited Authors

  • Drea, CM; Place, NJ; Weldele, ML; Coscia, EM; Licht, P; Glickman, SE

Published Date

  • October 2002

Published In

Volume / Issue

  • 269 / 1504

Start / End Page

  • 1981 - 1987

PubMed ID

  • 12396496

Pubmed Central ID

  • 12396496

Electronic International Standard Serial Number (EISSN)

  • 1471-2954

International Standard Serial Number (ISSN)

  • 0962-8452

Digital Object Identifier (DOI)

  • 10.1098/rspb.2002.2109

Language

  • eng