Mate Choice Copying Research Articles

Female mate choice copying increases egg survival rate but does not reduce mate-sampling cost in the barred-chin blenny

Female mate choice copying is assumed to increase the opportunity for sexual selection; however, this phenomenon has only been evaluated for a few species in the wild. This study confirmed the presence of female mate choice copying in a wild population of the paternal brooding blenny Rhabdoblennius nitidus, with the behaviour of the first copying females being repeatedly copied by subsequent females. Usually, parental phase males have lower mating success than courtship phase males; however, we manipulated parental phase males to mate with a demonstrator female, causing these males to be repeatedly chosen by other females. We then tested the benefit of mate choice copying in the wild. Our observations of female mate sampling do not support the hypothesis that mate choice copying causes a decline in the number of nests visited by females, time spent mate sampling and male harassment. All copying females mated with males tending the eggs of other females, whereas the majority of other females mated with males not tending eggs. Thus, it is highly possible that copying behaviour reduced the risk of egg desertion by males, which occurs when small numbers of eggs are tended.

Mate Copying: An Adaptive Sexual Selection Strategy

Mate Copying (or Mate Choice Copying) describes a strategy of mate choice. In this review, we demonstrate the basic concepts and the research paradigms of mate copying and show how the related factors work in this process. Such recent achievements and developing trend in this field are summarized as the gender effect (compared with men, women are more likely to use mate copying in mate choice), and other factors, which have impact on mate copying, like physical attractiveness, age, sexual strategy and sexual experience, etc. Further implications are discussed that the process of generalization of mate copying is one of the reasons causing the in-group congruent and inter-group incongruent effects on mate preferences. Finally, we conclude that mate copying is an adaptive social-learning-based strategy on sexual selection.

Homosexual behaviour increases male attractiveness to females

Male homosexual behaviour-although found in most extant clades across the Animal Kingdom-remains a conundrum, as same-sex mating should decrease male reproductive fitness. In most species, however, males that engage in same-sex sexual behaviour also mate with females, and in theory, same-sex mating could even increase male reproductive fitness if males improve their chances of future heterosexual mating. Females regularly use social information to choose a mate; e.g. male attractiveness increases after a male has interacted sexually with a female (mate choice copying). Here, we demonstrate that males of the tropical freshwater fish Poecilia mexicana increase their attractiveness to females not only by opposite-sex, but likewise, through same-sex interactions. Hence, direct benefits for males of exhibiting homosexual behaviour may help explain its occurrence and persistence in species in which females rely on mate choice copying as one component of mate quality assessment.

Mate choice copying in two species of darters (Percidae: Etheostoma)

Mate choice copying is a form of social learning that is defined as the increased likelihood of an individual choosing a particular mate after observing another individual choosing that mate. Mate choice copying has been demonstrated in a range of taxonomic groups, but not usually for both sexes. Mate choice copying experiments were performed here using two congeneric sympatric darters, Etheostoma flabellare and E. zonale. In E. flabellare, males guard a nest site under a rock and care for developing eggs. In E. zonale, eggs are attached to filamentous green algae and neither sex provides parental care. Our results provide the first evidence that mate choice copying occurs in darters. Previously it was hypothesised that copying might be more common in species and sexes that provide parental care, the reasoning being that the costs of choosing poorly may be higher. However, mate choice copying was found in both sexes of E. zonale (no parental care) and in male but not female E. flabellare (male only parental care). Thus, the only group that did not mate choice copy was the one whose mate would be providing care, and even E. flabellare females copy the mate choice of other females by some definitions. The relationship, if any, between which sex provides parental care and whether copying occurs remains unclear, and the number of species for which such data are available is limited.

Estrogenic involvement in social learning, social recognition and pathogen avoidance

Sociality comes with specific cognitive skills that allow the proper processing of information about others (social recognition), as well as of information originating from others (social learning). Because sociality and social interactions can also facilitate the spread of infection among individuals the ability to recognize and avoid pathogen threat is also essential. We review here various studies primarily from the rodent literature supporting estrogenic involvement in the regulation of social recognition, social learning (socially acquired food preferences and mate choice copying) and the recognition and avoidance of infected and potentially infected individuals. We consider both genomic and rapid estrogenic effects involving estrogen receptors α and β, and G-protein coupled estrogen receptor 1, along with their interactions with neuropeptide systems in the processing of social stimuli and the regulation and expression of these various socially relevant behaviors.

I like who you like, but only if I like you: Female character affects mate-choice copying

Mate-choice copying is shown when women imitate the mate-choice preferences of other women. We propose that the preferences of women with a pleasant character should be more influential than those of women with an unpleasant character and further suggest that this should apply only when the female demonstrates active interest in the male, rather than disinterest. Here, we presented women as having either a pleasant or unpleasant character and found that observing pleasant women looking at men increased women’s preferences for those men, while observing unpleasant women looking at men had no effect on women’s preferences. Furthermore, the effect of being looked at by a pleasant woman was heightened when she was smiling. This suggests that judgements of facial attractiveness can be socially influenced and that character affects the degree of influence.

Rival presence leads to reversible changes in male mate choice of a desert dwelling ungulate

Gregarious animals often face the problem of unintended interception of information by group members, as almost all communicatory interactions occur in a public domain. For example, individuals may observe and copy the choices of others. Male mate choice copying in species with internal fertilization remains a conundrum, as both the copying and the copied male incur increased sperm competition risk (SCR), and males are predicted to evolve strategies to reduce SCR. Specifically, males that are at imminent risk of being copied should cease expressing mating preferences. In this study, we gave male sand gazelles (Gazella marica) an opportunity to choose between 2 stimulus females in a 24-h association preference test, then repeated testing for another 24 h either while an audience male was presented close to the focal male’s compartment or without an audience (control treatment). Overall, focal males were highly consistent in their choices between day 1 and day 2. However, after the audience was presented, they showed a distinct short-term response that lasted for approximately 1 h: focal males altered their preferences, that is, interacted more equally with the 2 females and even tended to spend more time near the initially nonpreferred female. We discuss this effect as a counterstrategy of resident males to reduce SCR arising when new males join the group. In our experiment, habituation to the continued presence of a rival that was experimentally prevented from approaching females may be responsible for why focal males returned to express mating preferences some time after the audience was presented.

Eavesdropping and signal matching in visual courtship displays of spiders

Eavesdropping on communication is widespread among animals, e.g. bystanders observing male-male contests, female mate choice copying and predator detection of prey cues. Some animals also exhibit signal matching, e.g. overlapping of competitors' acoustic signals in aggressive interactions. Fewer studies have examined male eavesdropping on conspecific courtship, although males could increase mating success by attending to others' behaviour and displaying whenever courtship is detected. In this study, we show that field-experienced male Schizocosa ocreata wolf spiders exhibit eavesdropping and signal matching when exposed to video playback of courting male conspecifics. Male spiders had longer bouts of interaction with a courting male stimulus, and more bouts of courtship signalling during and after the presence of a male on the video screen. Rates of courtship (leg tapping) displayed by individual focal males were correlated with the rates of the video exemplar to which they were exposed. These findings suggest male wolf spiders might gain information by eavesdropping on conspecific courtship and adjust performance to match that of rivals. This represents a novel finding, as these behaviours have previously been seen primarily among vertebrates.

Generalization in mate-choice copying in humans

There is much evidence that humans, as other species, are affected by social information when making mate-choice decisions. Witnessing a rival show interest in a member of the opposite sex tends to lead human observers of both sexes to thereafter rate that person as more appealing as a potential mate. However, how this occurs is not well understood. We investigate whether this effect is specific to the individual witnessed or will generalize to other potential mates with shared characteristics—that is, whether humans exhibit trait-based or just individual-based mate-choice copying. We found that whereas this kind of generalization did occur with some traits, it appeared to depend on age, and conspicuously, it did not occur with (inner) facial traits. We discuss possible explanations for the age specificity and cue specificity in terms of informational benefits and how people attend to unfamiliar faces. Key words: cultural transmission, generalization, mate choice, mate-choice copying, sexual selection, social learning. [Behav Ecol]

Diet Quality Affects Mate Choice in Domestic Female Canary Serinus canaria

Mate choice is the result of intra- and intersexual selection. Even though a consensus between females is often observed in favour of some males, different constraints can affect their choice. Context (early learning, mate-choice copying, prior experience, etc) and/or condition (genetics, body condition, age, etc) can deflect the choice of a female from its ‘standard of beauty’. In domestic canaries Serinus canaria, females display their acceptance of a male by producing a particular sexual behaviour called ‘copulation solicitation display’ (CSD). Previous studies have shown that the number and intensity of these CSDs are more important when females listen to sexy ‘A’ phrases with a rapid tempo (A16) in comparison with A phrases with a slow tempo (A8). In this study, we assess the relationship between food quality (highly or poorly diversified food during a short period) and female choosiness towards these two types of phrases. We confirm that females discriminate between A16 and A8. Nevertheless, the difference between the number of sexual responses towards A16 and A8 is weaker among females with a poorly diversified food diet in comparison with females with a highly diversified food diet. This suggests that even a short-term modification of condition could decrease females’ selectivity towards high-value stimuli and increase their response rates towards low-value signals.

Sperm competition risk affects male mate choice copying

Mate choice copying was mostly described as a strategy employed by females to assess the quality of potential mates, but also males can copy other males’ mate choice. An open question in this context is whether and how copying males evaluate sperm competition risk, as mating with a female that has already copulated with another male obviously sets the stage for intense sperm competition (i.e., in species with internal fertilization). Using the livebearing Atlantic molly (Poecilia mexicana) as a model, we asked (a) whether males of that species indeed copy other males’ choices, and if they do so, (b) whether copying males strategically adjust their behavior to sperm competition risk. We used an approach where focal males could first choose to associate with a large or a small stimulus female. Mate choice tests were then repeated after an “observation phase” during which either no model male was present (treatment 1, control) or the previously non-preferred female could be seen associating (treatment 2) or physically interacting (treatment 3) with a model male. We found that, after the observation phase, males spent considerably more time with the previously non-preferred female in treatment (2), i.e., they copied the model male’s choice. This effect was much weaker during treatment (3) where sexual interactions between the model male and the formerly non-preferred female were allowed. Males, therefore, seem to adjust their copying behavior strategically to the perceived risk of sperm competition.

Mate Choice Copying and Nonindependent Mate Choice: A Critical Review

The past two decades have witnessed an explosion of interest in nonindependent mate choice, i.e. female choice that is influenced by the choices of other females. This research has focused overwhelmingly on mate choice copying, which occurs when a female is more likely to mate with a previously mated male and reject a previously rejected male. I review the theoretical constructs of nonindependent mate choice and mate choice copying, and evaluate the general hypotheses that have been proposed to account for the adaptive significance of mate choice copying, namely that it serves to bypass the costs of mate choice or improve the discrimination accuracy of females. I discuss the standard experimental protocols that are employed in the study of mate choice copying and review empirical studies that have been conducted to date. Strengths and weaknesses of the mate choice copying research program are highlighted, as well as possible directions for future research.

Alloparental care increases mating success

When individuals defend and care for young that are not their own (alloparental care), it raises the question of what benefits might lead to the evolution and persistence of such care. Here, we examine how male and female preferences affect the direct benefits of alloparental care. In the tessellated darter, alloparental care by some males often follows nest abandonment by others (Stiver KA, Wolff S, Alonzo SH, in preparation). We hypothesize that alloparental care may have evolved due to mating benefits: Alloparental care could be favored if females prefer to breed at nests that contain eggs. We found that, on average, males and females prefer nests with young eggs to those without eggs. Consequently, although young eggs increase the attractiveness of the nest, this positive effect is lost as the age of the eggs on the nest increases. We also found that alloparental care is costly in terms of future potential mating success as the amount of new eggs deposited in a nest decreases as nests become more filled. Therefore, alloparental males may initially increase their attractiveness to females by defending nests with another male’s eggs but still potentially gain fewer eggs relative to those received by males defending empty nests. Our findings shed light on the evolution of alloparental care in the tessellated darter, suggesting that female mating preferences may underlie this well-documented cooperative relationship between males. Key words: cooperation, female choice, mate-choice copying, predation dilution, sexual selection, tessellated darter. [Behav Ecol]

Misleading mollies: surface- but not cave-dwelling Poecilia mexicana males deceive competitors about mating preferences

Individuals providing misleading information to conspecifics may benefit from deception at the receiver's expense. A recent study (Plath et al., Curr Biol 18:1138–1141, 2008c) suggested that male Atlantic mollies (Poecilia mexicana) deceive rival males about their preferred mate. Here, we contrasted potentially deceptive behavior in surface-dwelling P. mexicana males to males of the cave form of that species (the cave molly). Unlike many other cavefishes, cave mollies have retained functional eyes and readily respond to visual stimuli. Males could interact freely with two females (large and small), and an audience male was visually presented during the second part of the tests. When observed during mate choice, males reduced their mating activity, but this reduction was significantly weaker in cave mollies. Overall, the expression of mating preferences (determined through frequencies of nipping and thrusting) declined in front of an audience; again, this effect was significantly weaker in the cave form. Reduced sexual activity and reduced expression of mating preferences can be interpreted as an attempt of the focal male to avoid unintended interception of information by the rival male. Surface but not cave molly males directed their first sexual interaction (when being observed by the rival male) towards the initially non-preferred female, suggesting that surface-dwelling males deceive rival males about their mating preferences. Deception by the focal males may be an adaptation to avoid sperm competition, since other males in their social environment may use public information and copy the focal male's mate choice. It seems that sending deceptive signals is evolutionarily regressed in the cave molly, since mate choice copying is unlikely to occur under naturally dark conditions, and also the potential to deceive rivals about mating preferences is probably very limited.

Mate Quality Bias: Sex Differences in Humans

In mate choice copying, a male is more likely to be chosen by other females simply by being observed mating. A recent finding is that women are influenced in their assessments of men by the phenotypic quality of males' sexual partners. We recently proposed that the term ‘mate quality bias’ should be used to differentiate this phenomenon from ‘mate choice copying’. Here, under the guise of a dating preferences survey we replicated and extended some earlier results. We found that when presented to female raters, men are more desirable dates when they are depicted as having had relatively attractive (versus relatively unattractive) former partners, an effect that appears to be moderated by a second variable, namely the former partner's age. We did not find evidence for this bias effect when men rate women whose profiles have been similarly manipulated. These findings suggest the operation of a sex-specific mate choice mechanism.

Nonindependent mate choice in monogamy

Nonindependent mate choice in monogamy

Mate choice copying and mate quality bias: are they different processes?

Mate choice copying and mate quality bias: are they different processes?

Do female fruit flies (Drosophila serrata) copy the mate choice of others?

Female mate-choice copying is a social learning phenomenon whereby a female's observation of a successful sexual interaction between a male and another female increases her likelihood of subsequently preferring that male. Although mate-choice copying has been documented in several vertebrate species, to our knowledge it has not yet been investigated in insects. Here, we investigated whether female mate-choice copying occurs in the fruit fly Drosophila serrata, a model system for the study of mate preferences and the sexual selection they generate. We used two complementary experiments in which focal females were given a choice between two males that differed in either their apparent (as determined visually by the focal female) or actual recent mating success. Mate-choice copying was evaluated by testing whether focal females mated more frequently with the 'preferred' male as opposed to the other male. In both experiments, however, we found no evidence for mate-choice copying. We discuss possible reasons for the apparent absence of mate-choice copying in this species.

Mate choice copying and mate quality bias: different processes, different species

Mate choice copying is the most studied type of nonindependent mate choice, in which the probability of a male being chosen by a female increases if he has previously been chosen by other females and decreases if he has been rejected. Recent studies suggest that what can sometimes influence females is not so much a male’s success at securing mates but the quality of the females that choose him. Here, we show that, though hitherto described as mate choice copying, this type of nonindependent mate choice is characterized by distinct evolutionary dynamics and ecological requirements, will have usually evolved in different species, and must therefore be urgently distinguished from mate choice copying. The term mate quality bias is suggested as an appropriate description of this phenomenon. Key words: evolutionary psychology, mate choice, mating skew, serial monogamy. [Behav Ecol]

Mate-choice copying in free-ranging Trinidadian guppies (Poecilia reticulata)

The social experiences of individuals can influence their mate-choice decisions. Mate-choice copying is considered to have occurred if an individual's observation of a sexual interaction between a male and a female increases its likelihood of subsequently preferring the individual observed mating. Although such copying behaviour has been documented extensively in the laboratory, there exists only very limited evidence for its occurrence in nature. Here, we experimentally investigated female mate-choice copying in a wild Trinidadian population of the guppy ( Poecilia reticulata ), a species that exhibits such copying behaviour in the laboratory. Using a pair of Plexiglas tanks placed in situ in a river in Trinidad, we presented free-ranging adult females with a binary choice of viewing and affiliating with either of two similar-sized stimulus males: one male was viewed next to a visible model (demonstrator) female and the other male viewed apparently alone (placed next to a pseudo-model female hidden from the subject females). Focal subject females preferred to associate with the stimulus male that was near and consorting with a model female than with the lone stimulus male. The results of a separate control experiment suggest that this observed female preference was sexual in nature rather than a simple shoaling response. We conclude that our results are consistent with mate-choice copying behaviour and suggest that female guppies can mate-choice copy in the wild when given the opportunity, as they do under laboratory conditions.