Female remating rate and pattern of sperm use suggest intense sperm competition in Drosophila antonietae (Diptera: Drosophilidae)

All Lepidoptera produce two sperm types: normal, nucleated ‘eupyrene’ sperm and anucleate ‘apyrene’ sperm. One hypothesis for the evolution of apyrene sperm suggests that they act to reduce female remating rate. Apyrene sperm require less resources to produce than do eupyrene sperm, and could delay remating by females by acting as a ‘cheap filler’, packing the spermatheca and thereby reducing receptivity. This would reduce the risk of sperm competition, giving a potential adaptive advantage to the male producing these sperm. This leads to the prediction that the probability of a female remating should correlate with the number of stored apyrene sperm, which has previously been supported by experiments using the green-veined white butterfly, Pieris napi . We repeated this experiment using the Indian meal moth, Plodia interpunctella . We find that in this species, eupyrene, not apyrene sperm number is the best predictor of female remating probability, indicating that the ‘cheap filler’ hypothesis for the function of apyrene sperm is not well supported in Pl. interpunctella .

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Female remating and sperm competition patterns in a terrestrial crustacean

Animal Behaviour ◽

10.1006/anbe.2002.4000 ◽

2002 ◽

Vol 64 (4) ◽

pp. 569-577 ◽

Cited By ~ 28

Author(s):

J. Moreau ◽

S. Seguin ◽

Y. Caubet ◽

T. Rigaud

Keyword(s):

Sperm Competition ◽

Female Remating

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Males adjust their manipulation of female remating in response to sperm competition risk

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2020.1238 ◽

2020 ◽

Vol 287 (1934) ◽

pp. 20201238

Author(s):

Joe A. Moschilla ◽

Joseph L. Tomkins ◽

Leigh W. Simmons

Keyword(s):

Sperm Competition ◽

Perceived Risk ◽

Mating Behaviour ◽

Reproductive Behaviour ◽

Field Crickets ◽

Female Remating ◽

Sperm Competition Risk ◽

Strategic Allocation ◽

Free Environment ◽

The Impact

To reduce the potential for sperm competition, male insects are thought to inhibit the post-mating reproductive behaviour of females through receptivity-inhibiting compounds transferred in the ejaculate. Selection is expected to favour phenotypic plasticity in male post-copulatory expenditure, with males investing strategically in response to their perceived risk of sperm competition. However, the impact that socially cued strategic allocation might have on female post-mating behaviour has rarely been assessed. Here, we varied male perception of sperm competition risk, both prior to and during mating, to determine if a male's competitive environment impacts the extent to which he manipulates female remating behaviour. We found that female Australian field crickets ( Teleogryllus oceanicus ) mated to males that were reared under sperm competition risk emerged from a shelter in search of male song sooner than did females mated to males reared without risk, but only when mating occurred in a risk-free environment. We also found that females reared in a silent environment where potential mates were scarce emerged from the shelter sooner than females exposed to male calls during development. Collectively, our findings suggest complex interacting effects of male and female sociosexual environments on female post-mating sexual receptivity.

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Relationships between male attractiveness, female remating, and sperm competition in the cigarette beetle

Behavioral Ecology and Sociobiology ◽

10.1007/s00265-016-2229-5 ◽

2016 ◽

Vol 71 (1) ◽

Cited By ~ 6

Author(s):

Masako Katsuki ◽

Haruhi Fujiwara ◽

Satoko Kodera ◽

Yû Suzaki ◽

Rikiya Sasaki ◽

...

Keyword(s):

Sperm Competition ◽

Cigarette Beetle ◽

Male Attractiveness ◽

Female Remating

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Genetic coordination of sperm morphology and seminal fluid proteins promotes male reproductive success in Drosophila melanogaster

10.1101/2021.11.15.468624 ◽

2021 ◽

Author(s):

Jake Galvin ◽

Erica Larson ◽

Sevan Yedigarian ◽

Mohammad Rahman ◽

Kirill Borziak ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Reproductive Success ◽

Sperm Competition ◽

Seminal Fluid ◽

Fertilization Success ◽

Male Reproductive Success ◽

Sperm Length ◽

Seminal Fluid Proteins ◽

Female Remating ◽

Paternity Success

Spermatozoal morphology is highly variable both among and within species and in ways that can significantly impact fertilization success. In Drosophila melanogaster, paternity success depends on sperm length of both competing males and length of the female's primary sperm storage organ. We found that genes upregulated in long sperm testes are enriched for lncRNAs and seminal fluid proteins (Sfps). Transferred in seminal fluid to the female during mating, Sfps are secreted by the male accessory glands (AG) and affect female remating rate, physiology, and behavior with concomitant advantages for male reproductive success. Despite being upregulated in long sperm testes, they have no known function in testis tissue. We found that Sex Peptide and ovulin (Acp26Aa) knockouts resulted in shorter sperm, suggesting that Sfps may regulate sperm length during spermatogenesis. However, knockout of AG function did not affect sperm length, suggesting that AG expression has no influence on spermatogenic processes. We also found that long sperm males are better able to delay female remating, suggesting higher Sfp expression in AG. These results might suggest that long sperm males have a double advantage in sperm competition by both delaying female remating, likely through transfer of more Sfps, and by resisting sperm displacement. However, we also found that this extra advantage does not necessarily translate to more progeny or higher paternity success. Thus, we found that multiple components of the ejaculate coordinate to promote male reproductive success at different stages of reproduction, but the realized fitness advantages in sperm competition are uncertain.

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Selection on female remating interval is influenced by male sperm competition strategies and ejaculate characteristics

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2012.0044 ◽

2013 ◽

Vol 368 (1613) ◽

pp. 20120044 ◽

Cited By ~ 31

Author(s):

Suzanne H. Alonzo ◽

Tommaso Pizzari

Keyword(s):

Sperm Competition ◽

Reproductive Traits ◽

Female Fecundity ◽

Female Remating ◽

Multiple Components ◽

Female Survival ◽

Develop Theory ◽

Female Reproductive Traits ◽

Multiple Male ◽

Allocation Strategies

Female remating rate dictates the level of sperm competition in a population, and extensive research has focused on how sperm competition generates selection on male ejaculate allocation. Yet the way ejaculate allocation strategies in turn generate selection on female remating rates, which ultimately influence levels of sperm competition, has received much less consideration despite increasing evidence that both mating itself and ejaculate traits affect multiple components of female fitness. Here, we develop theory to examine how the effects of mating on female fertility, fecundity and mortality interact to generate selection on female remating rate. When males produce more fertile ejaculates, females are selected to mate less frequently, thus decreasing levels of sperm competition. This could in turn favour decreased male ejaculate allocation, which could subsequently lead to higher female remating. When remating simultaneously increases female fecundity and mortality, females are selected to mate more frequently, thus exacerbating sperm competition and favouring male traits that convey a competitive advantage even when harmful to female survival. While intuitive when considered separately, these predictions demonstrate the potential for complex coevolutionary dynamics between male ejaculate expenditure and female remating rate, and the correlated evolution of multiple male and female reproductive traits affecting mating, fertility and fecundity.

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