Abstract
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Compone nts of male semina l flui ds are known to stimulate fec undity and fertilit y
in females of numerous insect species and paternal effects on offspring phenotyp e are
also known, but no studies have yet demonstrated links between male effec ts on
female reproduction and tho se on progen y pheno type. In separate laboratory
experi ments emp loying 10-day-old virgin females of Cheilomenes sexm aculata(F.), we
varied male age and mating history to manipu late levels of male allo mones and
found that the magnitud e of paternal effects on progen y phenotyp e was correlated
with stimulation of female reproduction. Older virgin males remained in copula
longer than younger ones, induced higher levels of female fecundi ty, and sired
proge ny that developed faster to yield heavier adul ts. When male age was held
constant (13 days), egg fertili ty de clined as a function of previ ous male copulations,
proge ny develop mental times increased, and the adult weight of daughters decline d.
These results sug gest that male epigene tic effects on progeny pheno type act in
concert with female reproductive stimulation; both categories of effects increased as a
conseq uence of male celibacy ( facto r accumulation), and dim inished as a function of
previ ous matings ( factor depletio n). Male facto rs that influence female reproduc tion
are implicated in sexual conflict an d parental effects may extend this conflic t to
offspring pheno type. Whereas mothers control the timin g of oviposition events and
can use maternal effect s to tailor progeny phenot ypes to prevaili ng or anticip ated
conditions, fathers canno t. Since females remate and dilu te paternit y in polyandrous
systems, paternal fitne ss wil l be increased by link ing paternal effect s to female
fecundi ty stimulation, so that more benefit s accrue to the male ’s own progeny.
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