Promiscuous mating systems provide the opportunity for females to bias fertilization toward particular males.However,distinguishing between male sperm com-petition and active female sperm choice is difficult for speci...Promiscuous mating systems provide the opportunity for females to bias fertilization toward particular males.However,distinguishing between male sperm com-petition and active female sperm choice is difficult for species with internal fertilization.Nevertheless,species that store and use sperm of different males in different storing struc-tures and species where females are able to expel all or part of the ejaculates after cop-ulation may be able to bias fertilization.We report a series of experiments aimed at pro-viding evidence of female sperm choice in Euxesta eluta(Hendel),a species of ulidiid fly that expels and consumes ejaculates after copulation.We found no evidence of greater reproductive success for females mated singly,multiply with the same male,or mated multiply with different males.Female E.eluta possesses two spherical spermathecae and a bursa copulatrix for sperm storage,with a ventral receptacle.There was no significant difference in storing more sperm in spermathecae 24 h after copulation than immediately after copulation.Females mated with protein-fed males had greater reproductive success than similar females mated to protein-deprived males.Protein-fed females prevented to consume the ejaculate,retained more sperm when mated to protein-fed males than when mated to protein-deprived males.Our results suggest that female E.eluta can exert control of sperm retention of higher quality males through ejaculate ejection.展开更多
基金supported by the Fund for Scientific and Technological Research(FONCyT PICT 2018-03521).
文摘Promiscuous mating systems provide the opportunity for females to bias fertilization toward particular males.However,distinguishing between male sperm com-petition and active female sperm choice is difficult for species with internal fertilization.Nevertheless,species that store and use sperm of different males in different storing struc-tures and species where females are able to expel all or part of the ejaculates after cop-ulation may be able to bias fertilization.We report a series of experiments aimed at pro-viding evidence of female sperm choice in Euxesta eluta(Hendel),a species of ulidiid fly that expels and consumes ejaculates after copulation.We found no evidence of greater reproductive success for females mated singly,multiply with the same male,or mated multiply with different males.Female E.eluta possesses two spherical spermathecae and a bursa copulatrix for sperm storage,with a ventral receptacle.There was no significant difference in storing more sperm in spermathecae 24 h after copulation than immediately after copulation.Females mated with protein-fed males had greater reproductive success than similar females mated to protein-deprived males.Protein-fed females prevented to consume the ejaculate,retained more sperm when mated to protein-fed males than when mated to protein-deprived males.Our results suggest that female E.eluta can exert control of sperm retention of higher quality males through ejaculate ejection.