The authors present a study in which audience effects on male mating behaviour was analysed in several species of poeciliids a family of livebearing freshwater fish and related to mean sexual activity used as a proxy for sperm competition risk and aggressiveness. The kinetics of spermatogenesis is species-specific and determined by the seminiferous epithelium cycle length SECL. Copying and sexual selection. This has implications for sperm competitiveness, as this species exhibits a disassociated reproductive tactic, in that sperm stores are produced outside the breeding season, and thus cannot be replenished after mating. FPrime FWorkspace item: Lastly, I think that the scenario generated from comparative studies at species level may be explained by phylogenetic factors other than sexual selection. The email address should be the one you originally registered with F
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Materials and Methods

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View Article Google Scholar 6. This article was most recently revised and updated by John P. September 19, Copyright: However, neither relative testes size nor MSMR had any effect on the diameter of seminiferous tubules, the height of the seminiferous epithelium, or the number of Sertoli cells per gram of testis PGLS: View Article Google Scholar 7.
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Sperm competition: evolutionary causes and consequences.

The semen of the American fire beetle Neopyrochroa flabellata , for example, is spiked with the poisonous compound cantharidin. This sounds curious if considering that in all the examined species aggressive behaviors and dominance establishment are always observed during dyadic encounters. Yeah I know , but Im just lucky like that. How to cite this article. Recently added grants: By continuing to browse the site, you are agreeing to our use of cookies.
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Methods are described in detail, but I wonder if this is the exact protocol used in all experiments. Effects of sperm competition on spermatogenic traits. I see the difficulty in doing this with few species, as it is the case of the present study, but I would suggest the Authors to consider also this future perspective. The sex peptide that is floating free in the semen does its work quickly: In addition, the investment into plastic sperm-competitive traits creates supplementary energy costs.
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The effects of sperm competition

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