Correlates versus predictors of courtship success: courtship song in Drosophila silvestris and D. heteroneura

Males of the picture-winged flies Drosophila silvestris and D. heteroneura produce a sound during courtship wing vibration; successful courtships include more time spent in wing vibration. We clipped male wings to test whether this sound is a necessary signal for the success of male courtship. We tested females in no-choice tests and also in choice tests in which each female was provided with a clipped and normal male simultaneously. We found no differences in the probability of copulation for either species in no-choice tests, and no difference for the choice tests with D. heteroneuraSurprisingly, clipped males were significantly more successful than control males in the choice tests with D. silvestrisThe latencies to copulate did not differ by treatment in any tests. Consequently, the sound produced by courtship wing vibration does not influence male mating success and thus does not meet the most important criterion for being a sexual signal. We propose that the vibration of thoracic muscles, transmitted through the substrate or through the male's forelegs, could provide a sexual signal in these species.1997The Association for the Study of Animal Behaviour     

Temporal manipulation of ejaculate components by newly fertilized Drosophila melanogaster females

Observations of newly mated Drosophila melanogaster females suggest that females control the times at which components of the ejaculate cause behavioural and physiological changes characteristic of fertilized females. Females that were assayed immediately after they mated elicited as much courtship as they did when they were virgins, but were unreceptive to copulation. Within a few minutes of when they disengaged from copulation, most females performed ovipositor extrusion, which has been classified as a rejection behaviour, in response to courting males or males that had previously performed courtship. Most females that were assayed immediately after mating had already ovulated. The females, however, do not begin to lay eggs until 4-6 h after mating, at which time they elicit very little courtship (Scott & Richmond 1985, Anim. Behav., 33, 817-824). Our observations suggest that neither ovipositor extrusion nor male-synthesized pheromones that are transferred to females' cuticles during copulation inhibit males' courtship of newly fertilized females. Thus, males cannot determine that newly fertilized females are unreceptive to copulation. These observations also indicate that the failure of newly fertilized females to mate with males is not a consequence of the females' inability to elicit vigorous courtship. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.     

Sexual selection as a side-effect of sexual conflict in the seaweed fly, Coelopa ursina (Diptera: Coelopidae)

The mating system of the seaweed fly involves a premating struggle. When mounted, females violently try to remove the male. In this study 48% of premating struggles resulted in successful rejection of the male, 46% in copulation and 6% were terminated by the male. Large males had a mating advantage. However, contrary to what would be predicted if this sexual selection occurred as a result of active female mate choice, we found a positive association between the duration of premating struggles and male size. A positive association was also found between the duration of premating struggles and male mating success, suggesting that large males may benefit through their superior ability to withstand female rejection. Large females rejected males more easily than small females, suggesting that the premating struggle has not evolved to allow mate assessment by females. We conclude that sexual selection is occurring as a side-effect of the female rejection response, which has probably evolved in order to avoid costs associated with copulation. Nevertheless, a sexual size dimorphism has evolved with males being larger and much more variable in size than females. (c) 1998 The Association for the Study of Animal Behaviour.     

Male traits, mating tactics and reproductive success in the buff-breasted sandpiper, Tryngites subruficollis

Buff-breasted sandpipers use a variety of mating tactics to acquire mates, including remaining at a single lek for most of the breeding season, attending multiple leks during the season, displaying solitarily or displaying both on leks and solitarily. We found that differences in body size, body condition, fluctuating asymmetry scores, wing coloration, territory location and behaviour (attraction, solicitation and agonistic) did not explain the observed variation in mating tactics used by males. Which males abandoned versus returned to leks was also not related to morphology or behaviour, and there was no tendency for males to join leks that were larger or smaller than the lek they abandoned. These results suggest that male desertion of leks was not dependent on a male's characteristics nor on the size of the lek he was presently attending. Males did join leks with larger males than their previous lek, perhaps to mate with females attracted to these larger 'hotshot' males. Males at both leks and solitary sites successfully mated. Lek tenure did not affect mating success, although lekking males appeared to mate more frequently than solitary males. Courtship disruption and to a lesser extent, female mimicry, were effective at preventing females from mating at leks, and may offer a partial explanation for female mating off leks. Our analysis that combined all males together within a year (regardless of mating tactic) indicated that males that attended leks for longer periods of time and that had fewer wing spots were significantly more likely to mate. Given some evidence that wing spotting declines with age, and that females inspect male underwings during courtship, the latter result suggests that female choice may play some role in determining male success. We suggest that male buff-breasted sandpipers may use alternative mating tactics more readily than males in other 'classic' lek-breeding species because: (1) unpredictable breeding conditions in this species' high arctic breeding range leads to low lek stability, which in turn hinders mate selection mechanisms mediated by male dominance and female choice; and (2) males are not constrained by morphological markings that indicate status or sex. Both characteristics may reduce the reproductive benefits associated with males adopting one mating tactic and result in a sort of scramble competition in which males switch between tactics as local conditions change.Copyright 1998 The Association for the Study of Animal Behaviour     

Social dynamics of group courtship behavior in male red-sided garter snakes (Thamnophis sirtalis parietalis).

Examined the social dynamics of the formation of mating balls (gatherings of males) during the mating period of red-sided garter snakes to determine whether the mating balls are formed simply because of a common attraction to the female or whether males are stimulated by the mating balls themselves. Nine test males and 9 stimulus females were used in tests, along with 55 other males, to measure the effect of other courting males. Results show that male Ss courted females more actively when other males were also courting the female than when they were alone with her, suggesting that the female is more attractive to the male when courted by other males. A positive correlation was observed between the number of additional males present and the amount of courtship activity shown by the test male toward the stimulus female. The extent to which the courtship activity of the test males was stimulated by the presence of additional courting males was not influenced by how actively the additional males courted. Results suggest that males are intrinsically stimulated by mating balls. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Female Japanese quail (Coturnix japonica) mated with males that harassed them are unlikely to lay fertilized eggs.

Results of previous studies of courtship and mating in Japanese quail (Coturnix japonica) suggest that females avoid conspecific males because, while courting and mating, males engage in behaviors that are potentially injurious to females. However, prior experiments provided no direct evidence that females avoided harassing males. Here the authors show that a female quail choosing between a previous sex partner and an unfamiliar male avoids the former if he engaged in relatively many potentially injurious acts while courting and mating, (Experiments 1 and 2) and that males behaving aggressively toward mates are less likely than are gentler males to fertilize the females' eggs (Experiment 3). Male sexual harassment appears to be a tactic both aversive to female quail and relatively ineffective in fertilizing them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The function of Barbary macaque copulation calls

In a wide variety of animal species, females produce vocalizations specific to mating contexts. It has been proposed that these copulation calls function to incite males to compete for access to the calling female. Two separate advantages of inciting male-male competition in this way have been put forward. The first suggests that as a result of calling, females are only mated by the highest ranking male in the vicinity (indirect mate choice hypothesis). The second proposes that copulation calling results in a female being mated by many males, thus promoting competition at the level of sperm (sperm competition hypothesis). In this paper, I give results from the first experimental study to test these hypotheses. Playback was used to examine the function of copulation calls of female Barbary macaques (Macaca sylvanus) in Gibraltar. Although rank did not affect lone males' likelihood of approaching copulation calls, when playbacks were given to pairs of males only the higher ranking individual approached. Moreover, females were mated significantly sooner after playback of their copulation call than after playback of a control stimulus. These results suggest that the copulation calls of female Barbary macaques play a key role in affecting patterns of male reproductive behaviour, not only providing an indirect mechanism of female choice, but also promoting sperm competition by reducing the interval between copulations. Potential fitness benefits of inciting male-male competition at these two levels are discussed.     

Male-male and male-female aggression may influence mating associations in wild octopuses (Abdopus aculeatus).

Abdopus aculeatus engages in frequent aggression and copulation, exhibits male mate-choice, and employs multiple mating tactics. Here we draw upon established hypotheses to compare male–male aggression (MMA) and male–female aggression (MFA), as they relate to their mating behavior in the wild. When contesting for females, males appear to balance mate preference (resource value) with perceived chances of winning contests (resource holding potential). Although males spent more time mating with and contesting for large “Adjacent Guarded” females (those occupying a den within arm’s reach of a large “Adjacent Guarding” male), they exhibited higher rates of aggression over nonadjacent “Temporarily Guarded” females that may be more accessible. The major determinant of male?male aggressive success was size, and this factor may dictate the expression of conditional mating tactics in males. “Adjacent Guarding” males were the largest and most aggressively successful males, earning the most time copulating with females. They are considered to have the highest resource holding potential (RHP) in MMA. By contrast, in MFA, some larger individuals fled from smaller individuals, indicating that RHP appears to be a function of both size and sex in intersexual aggression. This result suggests variation in aggressiveness, or potential for severe injury—even sexual cannibalism during MFA. Male–female aggression may also be influenced by the sexual nonreceptivity of some individuals, or attempts by both sexes to increase foraging behavior by delaying mate-guarding activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Copulatory behavior of deer mice (Peromyscus maniculatus): II. A study of some factors regulating the fine structure of behavior.

In 7 experiments on factors regulating copulatory behavior in deer mice, changes in copulatory behavior across series within a test reflected changes in both male and female, with the male apparently predominant. Even when mating with females of a species with a very different copulatory pattern (cactus mice), male deer mice retained the species-typical pattern. Mating in a 2-male/1-female condition produced little alteration in copulatory behavior from that in the 1-male/1-female condition. Under some test conditions, levels of aggressive behavior in the 2-male/1-female condition was considerable. There was generally covariation among body weight, social dominance, and copulation, with heavier males being dominant and ejaculating more often than lighter males. When females were in hormone-induced estrus, mount and intromission latencies were longer and ejaculation frequencies were lower than with either cycling or postpartum estrus. Significant differences between cycling and postpartum estrus were detectable with a within-Ss design. Mate familiarity had little effect on parameters of copulatory behavior once initiated. Effects of both male and female were detected when mating partners were changed between tests and test–retest correlation coefficients were calculated. (67 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Avoidance of Relatively Aggressive Male Japanese Quail (Coturnix japonica) by Sexually Experienced Conspecific Females.

Sexually experienced female Japanese quail (Coturnix japonica) that are offered a choice between 2 conspecific males previously observed engaging in an aggressive encounter prefer to affiliate with the less aggressive male. The authors determined whether this apparent preference for less aggressive males results from females approaching less aggressive individuals or avoiding more aggressive individuals. The authors found that females that had seen 2 males fight before choosing, in counterbalanced order, between each of them and a neutral stimulus were indifferent to less aggressive males but avoided more aggressive males. The results are consistent with the view that in species in which male courtship and mating are potentially harmful to females, females keep away from relatively aggressive males in order to avoid the physical punishment that can result from contact with them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of male pre-ejaculatory vocalizations on female receptive behavior in the rat (Rattus norvegicus).

Both male and female rats (Rattus norvegicus) emit ultrasounds during copulation. Bursts of ultrasounds from males that occur as ejaculation approaches are lower in frequency, longer in duration, and louder than those that appear earlier in the ejaculatory series. We attempted to determine if these pre-ejaculatory calls affect female sexual behavior. The behavior of females paired with devocalized males was compared with that of females paired with intact males, and in a second experiment tape-recorded vocalizations were played to females paired with devocalized males. Females were less receptive when paired with devocalized males; they were less likely to remain stationary when males attempted to mount. Playback of both types of calls restored female immobility toward control levels, although pre-ejaculatory calls were more effective than mating ones. Pre-ejaculatory calls restored running and trailing levels somewhat toward control level but to a lesser extent than female immobility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mating behaviour in the cellar spider, Pholcus phalangioides, indicates sperm mixing

In insects and spiders, the pattern of sperm priority is often attributed to the shape of the spermathecae and should entail marked consequences for mating behaviour. Since last-male priority is assumed to occur in haplogyne spiders such as the cellar spider, females of this species are predicted to be more attractive to males shortly before, than shortly after, egg laying and males may guard females after copulation until oviposition. To test these predictions, I individually marked spiders of a natural population and recorded their position and the distance between potential mating partners twice a day over 100 days. The distance between female and male was taken as a measure of the female's attractiveness. The behaviour of cellar spider males was not in accordance with the predictions; females were visited throughout the observation period with no significant increase in attractiveness before egg laying and there was no evidence for mate guarding. However, female attractiveness was correlated with female size, which was correlated with the number of eggs laid. Behaviour and genital morphology suggest sperm mixing occurs in this species. This is discussed in the light of conflicting data on sperm priority. Copyright 1998 The Association for the Study of Animal Behaviour.     

Mating behavior of the golden-orb-weaving spider, Nephila clavipes: I. Female receptivity and male courtship.

Observed 112 marked, free-moving female golden-orb-weaving spiders and the 161 males inhabiting their webs to determine factors that influence the likelihood of female sexual receptivity. Females were observed mating during a 2-day period after the final molt and later in adulthood when they fed. Results show that copulation differed at these times, with the most clearly defined and prolonged matings occurring during the 2-day period after the final molt. Juvenile females copulated only a few times for a few seconds. Various explanations for multiple matings are discussed, and it is suggested that females are situationally receptive throughout their adulthood because they cannot be assured that males will be present during the final molt period. Juvenile and adult females preyed on males but did so infrequently. Several of the instances of predation occurred within a few days after the final molt, suggesting that predation is caused by male persistence in attempting to copulate. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of ultrasonic vocalizations and male's urine on female rat readiness to mate.

Solitary estrous female Long-Evans rats were presented with ultrasonic vocalizations and/or urine of males to determine their effects on the females' subsequent copulatory behavior. Following exposure to ultrasounds, females exhibited a shorter latency to dart and a higher rate of darting when a male was presented. The vocalization effect was enhanced when male urine was present, but urine alone had no effect. The rate of copulation was also increased by the vocalization priming of the female. For a few individual females, ultrasounds elicited darting in the absence of a male. Results indicate that auditory cues, particularly in association with appropriate olfactory cues, prime estrous females for proceptive behavior. This increases both the likelihood and the rate of sexual performance and, therefore, the probability of successful mating. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Epitopes fused to F-pilin are incorporated into functional recombinant pili

Blue crabs mate immediately after the female's final moult. We tested the influence of female moult stage, sex ratio and male size on the pre-mating behaviour of both sexes, and the ability of males to pair with females and aggressively compete for access to females. We observed crabs in field enclosures and surveyed pre-copulatory mate-guarding patterns in the field. Female behaviour changed as they progressed through the final moult cycle, such that early moult-stage females avoided males, but late moult-stage females initiated pair formation. The changes in female behaviour influenced both the behaviour and pairing capability of males. Males courted and paired with late moult-stage females on their first attempt, but pursued early moult-stage females because their first attempts to pair often failed. In the field, early moult-stage females were paired less often than late moult-stage females. The pre-mating behaviour of both sexes also varied with sex ratio; when males were abundant, males traded courtship for forced capture and females courted less. Large males were more successful at take-overs, but did not pair more often with late moult-stage females, suggesting that large males do not consistently guard for less time than small males. The changes in female behaviour are consistent with the female's need to avoid the costs of guarding and suggest that females influence how pre-copulatory mate guarding occurs in this species.Copyright 1998 The Association for the Study of Animal Behaviour Copyright 1998 The Association for the Study of Animal Behaviour.     

Experience mediated reduction in courtship of Drosophila melanogaster in large and small chambers.

Drosophila melanogaster males show reduced courtship of virgin females and immature males after experience with either mated females or immature males. However, males experienced with mated females do not show a mating disadvantage, despite the expected reduction in courtship (Zawistowski & Richmond, 1985). This report presents experiments and data concerning D. melanogaster courtships and experience mediated courtship reductions in vials and small chambers. Males observed in small chambers displayed significantly higher levels of courtship toward virgin females, mated females, and immature males when compared with subjects observed in vials, with or without food. Males trained in vials with mated females do not subsequently show reduced levels of courtship in either small chambers or vials. It is suggested that the high level of courtship observed in the small chambers is not required to stimulate a female to mate because males mate more successfully in the vials, even though they court less. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Receptivity of the female rat (Rattus norvegicus) after male devocalization: A ventral perspective.

Male rats (Rattus norvegicus) emit at least two patterns of vocalization during copulation, the mating call and the pre-ejaculatory call. Both calls promote immobility of the female during lordosis, but the pre-ejaculatory calls are more effective. We undertook, through ventral observations of the mating pair, to determine if the female failed to assume or maintain the lordosis posture when mounted by a devocalized male and also to determine if the devocalized male was providing adequate stimulation to induce receptive behavior. Females were more likely to move away from the devocalized males before assuming the full lordosis posture. Furthermore, they were more likely to move away before the males had a chance to engage in intromissive behavior. However, when the females remained immobile along enough for the males to achieve a mount or intromission, there was little difference in the behavior of either animal that resulted from the devocalization of the male. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differences in behavioral responses to a competitive mating situation in two species of dwarf hamster (Phodopus campbelli and P. sungorus).

Social groups consisting of a female and two adult males, of two closely related species, Phodopus campbelli and P. sungorus, were observed during a 2-hr mating test. The behavioral analysis revealed (a) significant differences between the two species in the ability of the dominant male to exclude the subordinate male from mating with the estrous female and (b) significant changes in the pattern of copulation by the dominant male in response to the presence of a second male even when the second male was not mating with the female. Dominant male P. sungorus were always successful in preventing subordinate males from mating. In contrast, subordinate male P. campbelli mated with the female in 6 of 12 groups in spite of high levels of aggression and the potential for serious injury. When both P. campbelli males mated, dominant males ejaculated first and most frequently. The response to the presence of a second male in P. sungorus included an accelerated copulatory pattern, with decreased durations of individual ejaculatory series and postejaculatory refractory periods. This resulted in an average of one extra ejaculation during the first hour of testing. The temporal pattern of mating in P. campbelli was not accelerated by the presence of a second male, but the intromission/mount ratio was increased significantly, and the duration of the ejaculatory lock decreased. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Parental investment, reproductive success and polygyny in the lapwing, Vanellus vanellus

We studied the consequences of monogamy and polygyny for male and female lapwings at a site in northern England between 1993 and 1995. Males and females differed in breeding behaviour, and thus the pattern of reproductive investment: males contributed less time than females to the care of their offspring and more time to mating behaviour. We argue that this has resulted from sexual selection. Reproductive behaviour was similar in monogamous and polygynous individuals of both sexes. Male mating success was related to territory size, with males on the largest territories gaining more females. Polygynous male lapwings reared on average between 58 and 100% more chicks each year than monogamous males because of fewer complete breeding failures; between-year return rates of males to the area were similar. This would result in a strong advantage in terms of lifetime reproductive success for polygynous male lapwings. The seasonal breeding success of polygynous females was marginally, but not significantly, lower than that of monogamous females. Between-year return rates of monogamous and polygynous females were similar. Copyright 1998 The Association for the Study of Animal Behaviour.