Abstract
Standardized swim-up trials are used in in vitro fertilization clinics to select particularly motile spermatozoa in order to increase the probability of a successful fertilization. Such trials demonstrate that sperm with longer telomeres have higher motility and lower levels of DNA damage. Regardless of whether sperm motility, and successful swim-up to fertilization sites, is a direct or correlational effect of telomere length or DNA damage, covariation between telomere length and sperm performance predicts a relationship between telomere length and probability of paternity in sperm competition, a prediction that for ethical reasons cannot be tested on humans. Here, we test this prediction in sand lizards (Lacerta agilis) using experimental data from twice-mated females in a laboratory population, and telomere length in blood from the participating lizards. Female identity influenced paternity (while the mechanism was not identified), while relatively longer male telomeres predicted higher probability of paternity. We discuss potential mechanisms underpinning this result.
Highlights
Since Geoff Parker’s demonstration of post-copulatory sexual selection and its impact on relative fitness, the overwhelming ubiquity of this process across taxa and traits has been repeatedly confirmed [1,2]
We find that males with longer telomeres had a higher probability of siring offspring, while controlling for female identity in the model
We review the potential links between telomeres and relative fitness and find more support for correlational effects than directly causal ones; the magic bullet of telomere effects on fitness are still to be demonstrated [15]
Summary
Since Geoff Parker’s demonstration of post-copulatory sexual selection and its impact on relative fitness, the overwhelming ubiquity of this process across taxa and traits has been repeatedly confirmed [1,2]. Recent work shows that telomere length correlates with several aspects of fertility (e.g. sperm numbers per ejaculate [4,5], and embryonic survival [4]). This predicts that sperm with longer telomeres should arrive more quickly, or often, at sites for fertilization in the female reproductive tract, resulting in higher siring success, something that for ethical reasons cannot be tested in humans.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
