Male Mate Choice in a Natural Population of the Parasitic Copepod Lernaeocera Branchialis (Copepoda: Pennellidae)

AbstractVariations in age and sex structure of a natural population of the copepod Lernaeocera branchialis, parasitic on flounder, Platichthys flesus were examined in a 15-month study. Recent laboratory studies and literature on reproductive strategies indicate that male mate choice in this species should depend on the sex ratios of the parasite on its hosts, and on the age and mating status of females. Sex ratios suggested a strong intra-male competition for females. The ratio of chalimus 4 and virgin adult females (preferred stages) to adult males exceeded 1 female: 4 males on 50% of the hosts. In four out of the six sampling periods, more than 50% of hosts harboured more adult males than the total number of females. The males preference for the different female stages was estimated from the number of precopula and copula associations. The data were fitted to a logistic regression model. At most sex ratios, males preferred chalimus 4 and virgin adult females, and discriminated against younger stages. Mated females were about as attractive as the youngest larval stages at female-biased sex ratios, but they were chosen more frequently at strongly male-biased sex ratios. Most adult L. branchialis females had copulated more than once, and some had accommodated at least 5 ejaculates in the their sperm storage organs. The patterns of mate guarding and potential for sperm competition strongly suggest that L. branchialis males take the intrasexual competition into account when choosing mates. On this basis, they minimize guarding time and maximize the possibility of paternity.

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Synthesis and Outlook

Male Choice, Female Competition, and Female Ornaments in Sexual Selection ◽

10.1093/oso/9780198818946.003.0009 ◽

2021 ◽

pp. 153-161

Author(s):

Ingo Schlupp

Keyword(s):

Sexual Selection ◽

Mate Choice ◽

Sex Ratios ◽

Empirical Work ◽

Male Mate Choice ◽

Female Ornamentation ◽

Female Quality ◽

Investment In Reproduction ◽

Selection Research ◽

Male Mate

In this final chapter I want to briefly recap what I presented in the previous chapters and provide a few ideas on what might be done in the future to move the field forward. All three factors I discussed as relevant in male mate choice—male investment in reproduction, sex ratios, and variability in partner quality—are still emerging fields in sexual selection research and need more theoretical and empirical work. I suggest that variability in female quality is more important and more complex than currently known. The same is true for sex ratios. On the other hand, I suggest that sheer investment in gametes may be a little less important than currently assumed. Most importantly we need to explore the interactions of these three pathways to male mate choice. Female competition and also female ornamentation are still somewhat enigmatic and both topics are likely to grow in importance for our understanding of sexual selection. I think considering male and female choice together, as well as female and male competition will ultimately provide a more complete picture of Darwinian sexual selection.

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Exaggerated estrous swellings and male mate choice in primates: testing the reliable indicator hypothesis in the Amboseli baboons.

10.1101/007278 ◽

2014 ◽

Author(s):

Courtney L Fitzpatrick ◽

Jeanne Altmann ◽

Susan C Alberts

Keyword(s):

Mate Choice ◽

Mate Guarding ◽

Female Mate Choice ◽

Primate Species ◽

Reliable Indicator ◽

Male Mate Choice ◽

Papio Cynocephalus ◽

Cycle Number ◽

Fitness Measures ◽

Male Mate

The paradigm of competitive males vying to influence female mate choice has been repeatedly upheld, but, increasingly, studies also report competitive females and choosy males. One female trait that is commonly proposed to influence male mate choice is the exaggerated estrous swelling displayed by females of many Old World primate species. The reliable indicator hypothesis posits that females use the exaggerated swellings to compete for access to mates by advertising variation in female fitness. We tested the two main predictions of this hypothesis in a wild population of baboons (Papio cynocephalus). First, we examined the effect of swelling size on the probability of mate-guarding ('consortship') by the highest-ranking male and the behavior of those males that trailed consorshipts ('follower males'). Second, we asked whether a female's swelling size predicted several fitness measures. We found that high-ranking males do not prefer females with larger swellings (when controlling for cycle number and conception) and that females with larger swellings did not have higher reproductive success. In doing so, we have tested and rejected the reliable indicator hypothesis for the function of exaggerated swellings in cercopithecine primates. Furthermore, we found unambiguous evidence that males biased their mating decisions in favor of females who had experienced more sexual cycles since their most recent pregnancy. Thus, rather than tracking the potential differences in fitness between females, male baboons appear to track and target the potential for a given reproductive opportunity to result in fertilization.

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Mate guarding and male mate choice in the chameleon grasshopper Kosciuscola tristis (Orthoptera: Acrididae)

Journal of Ethology ◽

10.1007/s10164-017-0509-9 ◽

2017 ◽

Vol 35 (2) ◽

pp. 197-201 ◽

Cited By ~ 1

Author(s):

Peter C. Mahoney ◽

Nikolai J. Tatarnic ◽

James C. O’Hanlon ◽

Kate D. L. Umbers

Keyword(s):

Mate Choice ◽

Mate Guarding ◽

Male Mate Choice ◽

Male Mate

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Mate-guarding duration is mainly influenced by the risk of sperm competition and not by female quality in a golden orb-weaver spider

10.32942/osf.io/2u8tc ◽

2021 ◽

Author(s):

Lygia A. Del Matto ◽

Renato Chaves de Macedo Rego ◽

Eduardo S. A. Santos

Keyword(s):

Mate Choice ◽

Sperm Competition ◽

Body Condition ◽

Female Body ◽

Mate Guarding ◽

Male Mating ◽

Male Mate Choice ◽

High Quality ◽

Female Quality ◽

Male Mate

Males are expected to mate with as many females as possible, but can maximize their reproductive success through strategic mating decisions. For instance, males can increase their own fitness by mating with high quality females that produce more offspring. Additionally, males can adjust mating effort based on the relative distribution of females and male competitors. To test factors that influence male mate choice, we assessed male mating decisions in the golden-web spider, Trichonephila clavipes (Nephilidae), a species in which females are polyandrous and males guard females before and after copulation occurs. We tested the hypothesis that males spend more time guarding high quality females that are spatially isolated, and when the risk of sperm competition is higher. We assessed solitary and aggregated female webs in the field and quantified female quality (i.e. female body condition), the risk of sperm competition (i.e. number of males in each female web), and mate-guarding duration (i.e. number of days each male spent in each web). We found that mate-guarding behaviour is influenced by the presence of male competitors. In addition, the type of web seems to moderately influence male mating decisions, with males spending more time guarding a female when on solitary webs. Finally, female body condition seems to play a small role in mate-guarding behaviour. As mate-guarding duration considerably increased per each additional male competitor in the web, and guarding behaviour prevents males from seeking additional mates, it seems that males do benefit from guarding females. We conclude that failing to guard a sexual partner promotes high costs derived from sperm competition, and a male cannot recover his relative loss in fertilization success by seeking and fertilizing more females. In addition, the search for more sexual partners can be constrained by possible high costs imposed by predators and fights against other males, which may explain why the type of web only moderately influenced male mate choice. Following the same rationale, if high-quality females are not easy to find and/or mating with a high-quality female demands much effort, males may search females and guard them regardless of female quality. In conclusion, the factor that most influences male mate-guarding behaviour among T. clavipes in the field is the risk of sperm competition.

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Mate searching by males of the intertidal amphipod Corophium volutator (Pallas)

Canadian Journal of Zoology ◽

10.1139/z96-162 ◽

1996 ◽

Vol 74 (8) ◽

pp. 1479-1484 ◽

Cited By ~ 24

Author(s):

M. R. Forbes ◽

J. Sherman Boates ◽

N. L. McNeil ◽

A. E. Brison

Keyword(s):

Mate Choice ◽

Choice Theory ◽

Mate Guarding ◽

Seasonal Distribution ◽

Adult Males ◽

Male Choice ◽

Corophium Volutator ◽

Mate Searching ◽

Searching Behaviour ◽

Adult Females

In this paper we describe the mate-searching behaviour of male Corophium volutator (Pallas), an intertidal amphipod. We expected male choice of mates because males invest in mating by mate guarding, and also because adult females greatly outnumber adult males at our study site. We predicted that males would choose large females carrying many eggs and females close to moulting or close to being receptive. We found that individual males "assessed" an average of ca. 5 females in their respective burrows before entering the burrow of a prospective mate. Males were more likely to cohabit with females that were close to being receptive than with females that were far from being receptive. Over the season, the size of mate-searching males declined, whereas the number of females encountered by males increased, which may relate to the seasonal distribution of receptive females. However, there were no differences in size between paired and unpaired females regardless of time of season. Our results support mate discrimination by males based on one criterion (stage of receptivity). The proximate and ultimate causes of the biased sex ratios of C. volutator need' to be determined before other predictions based on mate-choice theory can be made.

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