phaidra.vetmeduni.ac.at o:4852 DOI 10.1186/s12915-025-02245-4 Pre- and post-copulatory traits are affected by experimental inbreeding, but they are not correlated It has been suggested that the expression of males’ secondary sexual traits provides reliable indicators of their sperm traits, predicting positive correlations between pre- and post-copulatory traits (Fertility Indicator Hypothesis). Yet, it has also been suggested that males face life-history tradeoffs between investing into primary versus secondary sexual traits, predicting negative correlations (Sexual Allocation Tradeoff Hypothesis). These two hypotheses are not mutually exclusive when males’ sexual traits are condition-dependent and high-quality males are better able to invest into both pre- and post-copulatory traits than low-quality males. To test these hypotheses, we manipulated the genetic quality of wild-derived male house mice by experimental inbreeding and first tested whether inbreeding affects primary or secondary sexual traits (condition-dependent expression). We then tested whether pre- and post-copulatory traits are correlated. We recorded courtship behavior and vocalizations of the males during female contact and measured males’ reproductive organs, sperm quality, and the expression of four genes associated with spermatogenesis. eng Sexual Signals Inbreeding Depression Allocation Tradeoffs Ultrasonic Vocalizations Sperm Traits Wild House Mice Mus Musculus Musculus 2026-02-03T10:12:26.246Z LOMv1.0 Author BEGIN:VCARD VERSION:3.0 N:Nicolakis;Doris; FN:Doris Nicolakis X-ORCID:https://orcid.org/0000-0002-0478-4995 END:VCARD BEGIN:VCARD VERSION:3.0 N:Marconi;Maria Adelaide; FN:Maria Adelaide Marconi X-ORCID:https://orcid.org/0000-0003-3429-7415 END:VCARD BEGIN:VCARD VERSION:3.0 N:Auer;Kerstin E.; FN:Kerstin E. Auer X-ORCID:https://orcid.org/0000-0002-6399-1388 END:VCARD BEGIN:VCARD VERSION:3.0 N:Penn;Dustin J.; FN:Dustin J. Penn X-ORCID:https://orcid.org/0000-0002-5406-8065 END:VCARD BEGIN:VCARD VERSION:3.0 N:Zala;Sarah M.; FN:Sarah M. Zala X-ORCID:https://orcid.org/0000-0002-0698-5299 END:VCARD https://w3id.org/kim/hcrt/scheme https://w3id.org/kim/hcrt/text Textdokument Text LOMv1.0 yes https://creativecommons.org/licenses/by/4.0 application/pdf 2113578 https://phaidra.vetmeduni.ac.at/o:4852 https://phaidra.vetmeduni.ac.at/api/object/o:4852/thumbnail LOMv1.0 discipline