Behavioral Ecology and Sociobiology

, Volume 66, Issue 5, pp 691–695 | Cite as

Facultative pheromonal mimicry in snakes: “she-males” attract courtship only when it is useful

Original Paper


Males of many animal species mimic females, and thereby deceive rival males. Facultative shifts in posture, color, or movement allow a male using visually-based mimicry to adopt and terminate mimicry rapidly. Pheromonal mimicry is rare in vertebrates perhaps because it is difficult to redeploy pheromones rapidly enough to adjust male tactics to local conditions. In Manitoba garter snakes (Thamnophis sirtalis parietalis), female mimicry benefits males immediately after they have emerged from hibernation. While the snakes are cold and slow, courtship warms them and protects them against predatory crows. This benefit disappears as soon as the snakes are warm. We show that (unlike females) she-male garter snakes attract courting males only when they are cold. Low temperatures may suppress volatility of “less attractive” components of the pheromones (saturated methyl ketones) that she-males use to attract courtship, allowing male snakes to function as transvestites only when this tactic is beneficial.


Chemical communication Reproductive tactics Reptile sociality Sexual mimicry 



We thank Mike Wall and the Johnson family for assistance and the Australian Research Council for funding.

Ethical standards

All experiments reported in this paper comply with the current laws of the country in which they were performed.


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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  1. 1.School of Biological Sciences A08University of SydneySydneyAustralia
  2. 2.Department of ZoologyOregon State UniversityCorvallisUSA
  3. 3.Department of BiologyPennsylvania State UniversityUniversity ParkUSA

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