Show simple item record

dc.contributor.authorSchmoll, Tim
dc.contributor.authorRudolfsen, Geir
dc.contributor.authorSchielzeth, Holger
dc.contributor.authorKleven, Oddmund
dc.description.abstractIn species with internal fertilization, the female genital tract appears challenging to sperm, possibly resulting from selection on for example ovarian fluid to control sperm behaviour and, ultimately, fertilization. Few studies, however, have examined the effects of swimming media viscosities on sperm performance. We quantified effects of media viscosities on sperm velocity in promiscuous willow warblers Phylloscopus trochilus. We used both a reaction norm and a character-state approach to model phenotypic plasticity of sperm behaviour across three experimental media of different viscosities. Compared with a standard medium (Dulbecco's Modified Eagle Medium, DMEM), media enriched with 1% or 2% w/v methyl cellulose decreased sperm velocity by up to about 50%. Spermatozoa from experimental ejaculates of different males responded similarly to different viscosities, and a lack of covariance between elevations and slopes of individual velocity-by-viscosity reaction norms indicated that spermatozoa from high- and low-velocity ejaculates were slowed down by a similar degree when confronted with high-viscosity environments. Positive cross-environment (1% versus 2% cellulose) covariances of sperm velocity under the character-state approach suggested that sperm performance represents a transitive trait, with rank order of individual ejaculates maintained when expressed against different environmental backgrounds. Importantly, however, a lack of significant covariances in sperm velocity involving a cellulose concentration of 0% indicated that pure DMEM represented a qualitatively different environment, questioning the validity of this widely used standard medium for assaying sperm performance. Enriching sperm environments along ecologically relevant gradients prior to assessing sperm performance will strengthen explanatory power of in vitro studies of sperm behaviour.en_US
dc.rightsNavngivelse 4.0 Internasjonal*
dc.subjectcryptic female choiceen_US
dc.subjectovarian fluid viscosityen_US
dc.subjectphenotypic plasticityen_US
dc.subjectPhylloscopus trochilusen_US
dc.subjectsperm competitionen_US
dc.subjectsperm motilityen_US
dc.titleSperm velocity in a promiscuous bird across experimental media of different viscositiesen_US
dc.typePeer revieweden_US
dc.typeJournal articleen_US
dc.rights.holder© 2020 The Author(s)en_US
dc.subject.nsiVDP::Matematikk og Naturvitenskap: 400::Basale biofag: 470en_US
dc.source.journalProceedings of the Royal Society of London. Biological Sciencesen_US
dc.relation.projectEgen institusjon: The Norwegian institute for nature research (NINA)en_US
dc.relation.projectAndre: The Fram Centreen_US

Files in this item


This item appears in the following Collection(s)

Show simple item record

Navngivelse 4.0 Internasjonal
Except where otherwise noted, this item's license is described as Navngivelse 4.0 Internasjonal