Are baculum size and allometry a response to post-copulatory sexual selection in promiscuous males of the house mouse?

  • Alexander CsanádyEmail author
  • Silva Duranková
  • Erika Labancová
Original Paper


Great genital variation occurs across animal species, likely reflecting the operation of sexual selection. We quantified bacular, testicular, and vesicular size, variation, and allometry in house mice (Laurentii in: Mus musculus Linnaeus, Systema naturae 10th ed, Salvii, Stockholm, 1758) from the western Carpathians (Slovakia). We investigated whether baculum size is related to size of reproductive organs (testicular length and width, and vesicular length), and with body size (head-and-body length), which is not directly involved in reproduction. The corrected coefficient of variation (CV’) for all bacular, testicular, and vesicular traits was significantly higher than non-sexual somatic traits. The negative allometry and weak relationship between baculum size and head-and-body length obtained in presented study (OLS regression) suggest that the Mus musculus baculum is under stabilizing selection. We also assumed that penile width as related to bacular thickness could be a reliable indicator of quality during copulation.


Mus musculus Testicular and vesicle size Variability Os penis OLS regression 



We would like to express our sincere thanks to Milan Malenky, Ján Maťaš, Juraj Lechman, Miroslav Vavrek, and Andrej Mock for their help with trapping the mice and for general assistance provided. This study was supported by the Agency of the Ministry of Education. Science, Research and Sport of the Slovak Republic for the Structural Funds of EU (ITMS 26220120041). Our thanks also go to anonymous referees for their valuable comments on the manuscript. Finally, we would like to thank David McLean for proofreading the manuscript.

Compliance with ethical standards

Conflict of interest

Author Csanády declares that he has no conflict of interest. Author Duranková declares that she has no conflict of interest. Author Labancová declares that she has no conflict of interest.

Ethical approval

All applicable international, national, and/or institutional guidelines for the care and use of animals were followed.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Alexander Csanády
    • 1
    Email author
  • Silva Duranková
    • 1
  • Erika Labancová
    • 2
  1. 1.Department of Biology, Faculty of Humanities and Natural SciencesUniversity of PrešovPrešovSlovakia
  2. 2.StropkovSlovakia

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