Male reproductive success is influenced by competitive interactions during precopulatory and postcopulatory selective episodes.
Consequently, males can gain reproductive advantages during precopulatory contest competition by investing in weaponry
and during postcopulatory sperm competition by investing in ejaculates. However, recent theory predicts male expenditure on
weaponry and ejaculates should be subject to a trade-off, and should vary under increasing risk and intensity of sperm competition.
Here, we provide the first comparative analysis of the prediction that expenditure on weaponry should be negatively associated
with expenditure on testes mass. Specifically, we assess how sexual selection influences the evolution of primary and secondary
sexual traits among pinnipeds (seals, sea lions, and walruses). Using recently developed comparative methods, we demonstrate
that sexual selection promotes rapid divergence in body mass, sexual size dimorphism (SSD), and genital morphology. We then
show that genital length appears to be positively associated with the strength of postcopulatory sexual selection. However,
subsequent analyses reveal that both genital length and testes mass are negatively associated with investment in precopulatory
weaponry. Thus, our results are congruent with recent theoretical predictions of contest-based sperm competition models. We
discuss the possible role of trade-offs and allometry in influencing patterns of reproductive trait evolution in pinnipeds.
%0 Journal Article
%1 fitzpatrick_male_2012
%A Fitzpatrick, John L.
%A Almbro, Maria
%A Gonzalez-Voyer, Alejandro
%A Kolm, Niclas
%A Simmons, Leigh W.
%D 2012
%J Evolution
%K controlled dimorphism, mammals, marine phylogenetically phylogenetics, pinnipeds, regression, selection sex
%P no--no
%R 10.1111/j.1558-5646.2012.01713.x
%T Male contest competition and the coevolution of weaponry and testes in pinnipeds
%U http://doi.wiley.com/10.1111/j.1558-5646.2012.01713.x
%X Male reproductive success is influenced by competitive interactions during precopulatory and postcopulatory selective episodes.
Consequently, males can gain reproductive advantages during precopulatory contest competition by investing in weaponry
and during postcopulatory sperm competition by investing in ejaculates. However, recent theory predicts male expenditure on
weaponry and ejaculates should be subject to a trade-off, and should vary under increasing risk and intensity of sperm competition.
Here, we provide the first comparative analysis of the prediction that expenditure on weaponry should be negatively associated
with expenditure on testes mass. Specifically, we assess how sexual selection influences the evolution of primary and secondary
sexual traits among pinnipeds (seals, sea lions, and walruses). Using recently developed comparative methods, we demonstrate
that sexual selection promotes rapid divergence in body mass, sexual size dimorphism (SSD), and genital morphology. We then
show that genital length appears to be positively associated with the strength of postcopulatory sexual selection. However,
subsequent analyses reveal that both genital length and testes mass are negatively associated with investment in precopulatory
weaponry. Thus, our results are congruent with recent theoretical predictions of contest-based sperm competition models. We
discuss the possible role of trade-offs and allometry in influencing patterns of reproductive trait evolution in pinnipeds.
@article{fitzpatrick_male_2012,
abstract = {Male reproductive success is influenced by competitive interactions during precopulatory and postcopulatory selective episodes.
Consequently, males can gain reproductive advantages during precopulatory contest competition by investing in weaponry
and during postcopulatory sperm competition by investing in ejaculates. However, recent theory predicts male expenditure on
weaponry and ejaculates should be subject to a trade-off, and should vary under increasing risk and intensity of sperm competition.
Here, we provide the first comparative analysis of the prediction that expenditure on weaponry should be negatively associated
with expenditure on testes mass. Specifically, we assess how sexual selection influences the evolution of primary and secondary
sexual traits among pinnipeds (seals, sea lions, and walruses). Using recently developed comparative methods, we demonstrate
that sexual selection promotes rapid divergence in body mass, sexual size dimorphism (SSD), and genital morphology. We then
show that genital length appears to be positively associated with the strength of postcopulatory sexual selection. However,
subsequent analyses reveal that both genital length and testes mass are negatively associated with investment in precopulatory
weaponry. Thus, our results are congruent with recent theoretical predictions of contest-based sperm competition models. We
discuss the possible role of trade-offs and allometry in influencing patterns of reproductive trait evolution in pinnipeds.},
added-at = {2017-01-09T13:57:26.000+0100},
author = {Fitzpatrick, John L. and Almbro, Maria and Gonzalez-Voyer, Alejandro and Kolm, Niclas and Simmons, Leigh W.},
biburl = {https://www.bibsonomy.org/bibtex/2637647cf11a03aa3d097d06da7bee859/yourwelcome},
doi = {10.1111/j.1558-5646.2012.01713.x},
interhash = {d60fc5779432afa19d6933bcb2299635},
intrahash = {637647cf11a03aa3d097d06da7bee859},
issn = {00143820},
journal = {Evolution},
keywords = {controlled dimorphism, mammals, marine phylogenetically phylogenetics, pinnipeds, regression, selection sex},
month = jul,
pages = {no--no},
timestamp = {2017-01-09T14:01:11.000+0100},
title = {Male contest competition and the coevolution of weaponry and testes in pinnipeds},
url = {http://doi.wiley.com/10.1111/j.1558-5646.2012.01713.x},
urldate = {2012-07-23},
year = 2012
}