Sexual selection and reproductive success in males of the bicolor damselfish, Eupomacentrus partitus (Pisces: Pomacentridae)

Sexual selection theory predicts that males should be promiscuous to maximize their reproductive success, while females should be choosy. Yet females of many taxa often produce progeny sired by multiple males, indicating that promiscuity can be important for the reproductive success of females. Promiscuity may enhance the fitness of females if it increases the genetic quality, or the genetic variety, and thus the viability of their offspring. We quantified the number of sires per clutch in a population of Northern Map Turtles (Graptemys geographica (LeSueur, 1817)) in Lake Opinicon, Ontario, Canada, and tested whether the number of sires affects several metrics of viability in hatchlings. Based on the most conservative estimate, at least 71% of clutches in this population are sired by multiple males, but there was no evidence that larger clutches are sired by more males. Clutches sired by more males had higher hatching success and survival, but the differences were not statistically significant. We did not find any effect of the number of sires on hatchling morphology or locomotor performance. Collectively, our results partially support the hypothesis that promiscuity can increase the reproductive success of female Northern Map Turtles.

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Size does not matter for male Marbled Salamanders (Ambystoma opacum)

Canadian Journal of Zoology ◽

10.1139/cjz-2014-0229 ◽

2015 ◽

Vol 93 (10) ◽

pp. 735-740

Author(s):

D.A. Croshaw ◽

J.H.K. Pechmann

Keyword(s):

Sexual Selection ◽

Body Size ◽

Reproductive Success ◽

Large Male ◽

Male Mating ◽

Ambystoma Opacum ◽

Positive Assortative Mating ◽

Important Trait ◽

Breeding Groups ◽

Gravid Females

Understanding the phenotypic attributes that contribute to variance in mating and reproductive success is crucial in the study of evolution by sexual selection. In many animals, body size is an important trait because larger individuals enjoy greater fitness due to the ability to secure more mates and produce more offspring. Among males, this outcome is largely mediated by greater success in competition with rival males and (or) advantages in attractiveness to females. Here we tested the hypothesis that large male Marbled Salamanders (Ambystoma opacum (Gravenhorst, 1807)) mate with more females and produce more offspring than small males. In experimental breeding groups, we included males chosen specifically to represent a range of sizes. After gravid females mated and nested freely, we collected egg clutches and genotyped all adults and samples of hatchlings with highly variable microsatellite markers to assign paternity. Size had little effect on male mating and reproductive success. Breeding males were not bigger than nonbreeding males, mates of polyandrous females were not smaller than those of monogamous females, and there was no evidence for positive assortative mating by size. Although body size did not matter for male Marbled Salamanders, we documented considerable fitness variation and discuss alternative traits that could be undergoing sexual selection.

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Long-term mating positively predicts both reproductive fitness and parental investment

Journal of Biosocial Science ◽

10.1017/s0021932021000407 ◽

2021 ◽

pp. 1-12

Author(s):

Janko Međedović

Keyword(s):

Sexual Selection ◽

Reproductive Success ◽

Parental Investment ◽

Reproductive Fitness ◽

Human Populations ◽

Number Of Children ◽

Fitness Indicators ◽

Number Of Sexual Partners ◽

Sexual Selection Theory

Abstract Empirical data on the relations between mating and reproductive success are rare for humans, especially for industrial and post-industrial populations. Existing data show that mating (and especially long-term mating) can be beneficial for fitness, especially that of males. This finding is in line with the hypothesis of sexual selection operating in human populations. The present research expands on previous studies by: 1) analysing additional fitness indicators, including having children with different partners; 2) including parental investment in the analysis as another important marker of sexual selection; 3) analysing several mediators between mating, reproductive fitness and parental investment, i.e. age of first and last reproduction and desired number of children. The data were obtained in 2019 from a sample of parents living in Serbia (N=497). The findings showed that long-term mating (duration of longest partner relationship) was positively related to parental investment and number of offspring and grand-offspring. Furthermore, the link between long-term mating and reproductive success was completely mediated by the age of first reproduction and desired number of children. Short-term mating (number of sexual partners) was marginally positively related to the number of children participants had with different partners and negatively related to parental investment. No sex differences in the link between mating, fitness and parental investment were detected. In general, the signatures of sexual selection were weak in the present data, but those that were detected were in line with sexual selection theory. The present findings provide a deeper insight into the adaptive function of mating and also the mechanism of how mating is beneficial for fitness.

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Voice, Sexual Selection, and Reproductive Success

Voice Attractiveness - Prosody, Phonology and Phonetics ◽

10.1007/978-981-15-6627-1_7 ◽

2020 ◽

pp. 125-138

Author(s):

Alexandre Suire ◽

Michel Raymond ◽

Melissa Barkat-Defradas

Keyword(s):

Sexual Selection ◽

Reproductive Success

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Do metrics of sexual selection conform to Bateman's principles in a wind-pollinated plant?

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.0532 ◽

2019 ◽

Vol 286 (1905) ◽

pp. 20190532 ◽

Cited By ~ 6

Author(s):

Jeanne Tonnabel ◽

Patrice David ◽

John R. Pannell

Keyword(s):

Spatial Distribution ◽

Sexual Selection ◽

Reproductive Success ◽

Pollen Dispersal ◽

Male Fitness ◽

Female Fitness ◽

Dioecious Plant ◽

Common Gardens ◽

Mate Acquisition ◽

Mercurialis Annua

Bateman's principles posit that male fitness varies more, and relies more on mate acquisition, than female fitness. While Bateman's principles should apply to any organism producing gametes of variable sizes, their application to plants is potentially complicated by the high levels of polyandry suspected for plants, and by variation in the spatial distribution of prospective mates. Here we quantify the intensity of sexual selection by classical Bateman metrics using two common gardens of the wind-pollinated dioecious plant Mercurialis annua . Consistent with Bateman's principles, males displayed significantly positive Bateman gradients (a regression of fitness on mate number), whereas the reproductive success of females was independent of their ability to access mates. A large part of male fitness was explained by their mate number, which in turn was associated with males' abilities to disperse pollen. Our results suggest that sexual selection can act in plant species in much the same way as in many animals, increasing the number of mates through traits that promote pollen dispersal.

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Behavioural and genetic analyses of mate choice and reproductive success in two Chinook salmon populations

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2012-0415 ◽

2013 ◽

Vol 70 (2) ◽

pp. 263-270 ◽

Cited By ~ 7

Author(s):

Melissa L. Evans ◽

Bryan D. Neff ◽

Daniel D. Heath

Keyword(s):

Sexual Selection ◽

Natural Selection ◽

Reproductive Success ◽

Mate Choice ◽

Mhc Class Ii ◽

Chinook Salmon ◽

Oncorhynchus Tshawytscha ◽

Mating Behaviour ◽

Selection Pressures ◽

Evolutionary Force

Sexual selection is recognized as an important evolutionary force in salmon. However, relatively little is known about variation in sexual selection pressures across salmon populations or the potential role of natural selection as a driver of adaptive mating patterns. Here, we examine mating behaviour and correlates of reproductive success in Chinook salmon (Oncorhynchus tshawytscha) from the Quinsam and Little Qualicum rivers in British Columbia, Canada — two populations for which we have previously found evidence of natural selection operating on major histocompatibility complex (MHC) genes. In both populations, males courted females and exhibited dominance behaviour towards other males, and the frequency of each behaviour was positively associated with reproductive success. Males were more aggressive towards females with whom they would produce offspring of low or high MHC class II diversity, and the offspring of males from the Quinsam River exhibited higher diversity at the MHC class I than expected. We discuss our results in relation to local natural selection pressures on the MHC and the potential for MHC-dependent mate choice.

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Breast asymmetry, sexual selection, and human reproductive success

Ethology and Sociobiology ◽

10.1016/0162-3095(95)00002-3 ◽

1995 ◽

Vol 16 (3) ◽

pp. 207-219 ◽

Cited By ~ 83

Author(s):

Anders Pape Møller ◽

Manuel Soler ◽

Randy Thornhill

Keyword(s):

Sexual Selection ◽

Reproductive Success ◽

Breast Asymmetry ◽

Human Reproductive

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Sexual conflict inGerris gillettei(Insecta: Hemiptera): influence of effective mating rate and morphology on reproductive success

Canadian Journal of Zoology ◽

10.1139/z2012-098 ◽

2012 ◽

Vol 90 (11) ◽

pp. 1297-1306 ◽

Cited By ~ 5

Author(s):

Marie-Claude Gagnon ◽

Pierre Duchesne ◽

Julie Turgeon

Keyword(s):

Sexual Selection ◽

Reproductive Success ◽

Sexual Conflict ◽

Water Strider ◽

Mating Rate ◽

Multiple Matings ◽

Males And Females ◽

Genetic Mating System ◽

Selection Framework ◽

Resistance Traits

In water striders, the interests of both sexes diverge over the decision to mate, leading to precopulatory sexual conflict. The influence of mating rate and key persistence and resistance traits on reproductive success has seldom been investigated in the context of multiple matings. We used amplified fragment length polymorphism (AFLP) based genetic parentage analyses to estimate mating and reproductive success in Gerris gillettei Lethierry and Severin, 1896, while allowing for free multiple matings. We tested the hypotheses that males should display stronger opportunity for sexual selection and steeper Bateman gradients. In each sex, persistence and resistance traits should also impact mating and reproductive success. Surprisingly, males and females had similarly high and variable effective mating rates (i.e., number of genetic partners), and both sexes produce more offspring when mating with more partners. As predicted, exaggerated persistence traits allowed males to mate with more partners and sire more offspring. However, we found no evidence for an impact of resistance traits for females. The mating environment may have favoured low resistance in females, but high promiscuity can be beneficial for females. This first description of the genetic mating system for a water strider species suggests that the determinants of fitness can be further deciphered using the sexual selection framework.

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Sexual selection and hermaphroditic organisms: Testing theory

Current Zoology ◽

10.1093/czoolo/59.4.579 ◽

2013 ◽

Vol 59 (4) ◽

pp. 579-588 ◽

Cited By ~ 4

Author(s):

Janet L. Leonard

Keyword(s):

Sexual Selection ◽

Reproductive Success ◽

Multiple Mating ◽

The Other ◽

Operational Sex Ratio ◽

Sexual Role ◽

Sexual Roles ◽

Sexual Selection Theory ◽

Variance In Reproductive Success ◽

Simultaneous Hermaphrodites

Abstract Sexual selection is widespread if not ubiquitous in hermaphroditic organisms. Although many phenomena that have been described as sexual selection in gonochores, (e.g. harem polygamy, multiple mating, elaborate courtship, even secondary sexual characters) can be found in some hermaphrodites, what is more interesting is the ways in which sexual selection in hermaphrodites may differ from dioecious taxa. In hermaphrodites, an individual’s mating success includes its success from both sexual roles. Secondly, in many simultaneously hermaphroditic taxa there is strong evidence of sexual selection and yet the operational sex ratio is 1:1, by definition. Many simultaneous hermaphrodites have elaborate courtship and genital anatomy, suggesting sexual selection plays an important role in reproductive success. Sperm competition and cryptic female choice mean that the number of mates acquired is not necessarily a predictor of reproductive success. Even in simultaneous hermaphrodites with reciprocal mating, variance in reproductive success through the male role and through the female role may differ in a population. Moreover hermaphrodites may choose to emphasize one sexual role over the other. Data suggest that the preferred role varies in hermaphrodites, which creates an opportunity to test fundamental predictions and assumptions of sexual selection theory. Hermaphrodites may vary their emphasis on one sexual role over the other either developmentally or behaviorally in response to environmental or social parameters. How they use this capability in acquiring more or higher quality mates still requires study.

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