eCite Digital Repository

Cryptic male choice: experimental evidence of sperm sex ratio and seminal fluid adjustment in relation to coital rate


Edwards, AM and Cameron, EZ, Cryptic male choice: experimental evidence of sperm sex ratio and seminal fluid adjustment in relation to coital rate, Reproduction, Fertility and Development, 29 pp. 1401-1404. ISSN 1031-3613 (2017) [Refereed Article]

Copyright Statement

Journal compilation copyright CSIRO 2017

DOI: doi:10.1071/RD16123


The differential allocation hypothesis suggests that a mother should adjust the sex of offspring in relation to her mate’s attractiveness, thereby increasing future reproductive fitness when her sons inherit the attractive traits. More attractive males have been shown to sire more sons, but it is possible that the sex ratio skew could be a result of paternal rather than maternal manipulation, which would be a more parsimonious explanation. We manipulated coital rate (an indicator of attractiveness) in laboratory mice and showed that males that mate more often have higher levels of glucose in their semen despite lower blood glucose levels. Since peri-conceptual glucose levels in utero increase male conceptus survival, this could result in male-biased sex ratios. The males that mated most also had more remaining X-chromosome-bearing-spermatozoa, suggesting depletion of Y-chromosome-bearing-spermatozoa during mating. We hypothesise that males may alter both seminal fluids and X : Y ratios in an ejaculate to influence subsequent sex ratios. Our results further support a paternal role in sex allocation.

Item Details

Item Type:Refereed Article
Keywords:sex allocation, reproductive physiology, attractiveness, paternal, differential allocation
Research Division:Biological Sciences
Research Group:Ecology
Research Field:Behavioural ecology
Objective Division:Environmental Management
Objective Group:Terrestrial systems and management
Objective Field:Terrestrial biodiversity
UTAS Author:Edwards, AM (Dr Amy Edwards)
UTAS Author:Cameron, EZ (Professor Elissa Cameron)
ID Code:117859
Year Published:2017
Funding Support:Australian Research Council (DP140103227)
Web of Science® Times Cited:7
Deposited By:Zoology
Deposited On:2017-06-28
Last Modified:2018-07-30

Repository Staff Only: item control page