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Animals vary in the complexity and size of the signal repertoire used in communication. Often, these behavioural repertoires include multiple signal types for the same process, for instance, courtship. In Enchenopa treehoppers (Hemiptera: Membracidae) mate-searching males produce plant-borne vibrational advertisement signals. Receptive females then respond to males with their own signals. Here we describe an additional signal type in the repertoire of these males. We collected nymphs in Wisconsin, USA, and recorded the spontaneous signalling bouts of adult males and duetting signals of females using laser vibrometry. Two-thirds of males produced the additional signal type, which differed in temporal and spectral features from the main male advertisement signals, whilst resembling female duetting signals in placement and acoustic features. Our findings suggest that this might be a female mimic signal. Overall, our findings highlight the diversity in the behavioural repertoire that animals may use for reproduction. [ABSTRACT FROM AUTHOR]

Females often choose mates based on their courtship signals. Males may signal their heritable genetic quality, defended resources, or parental care efforts; however, the reasons why females choose males based on their signals are often not clear. Here, we show that, in the fiddler crab Austruca perplexa , male signals (major-claw waving rates) were correlated with important characteristics of their defended resources (width and depth of breeding burrows). By using the male signals, females may be able to roughly predict the burrow quality and decide whether to enter and check the burrow characteristics. The signals are predicted to be honest because the female's final decision is based on burrow quality. Since females can reject males if their burrow quality is insufficient for breeding, the courtship efforts of deceptive males will be dismissed. The honesty of the signals is beneficial for both sexes and thus easily evolved in their signalling system. [ABSTRACT FROM AUTHOR]

We analysed heterosexual consortships in a free-ranging group of Japanese macaques in which adult females routinely perform female-to-male mounting (FMM). We tested whether FMM is more efficient (i.e., a 'supernormal courtship' behavioural pattern) than species-typical female-to-male sexual solicitations (FMSS) at prompting subsequent male-to-female mounts (MFM). In a context of high female-female competition for male mates, we found that (1) FMM functioned to focus the male consort partner's attention as efficiently as FMSS and prevented him from moving away, and (2) FMM was more efficient than species-typical FMSS at expediting MFM (i.e., the most fitness-enhancing sexual behaviour of a mating sequence). We concluded that FMM could be considered a supernormal courtship behavioural pattern in adult female Japanese macaques. This population-specific sexual adaptation may result from a combination of favourable socio-demographic conditions. This study has implications for the evolutionary history of non-conceptive mounting patterns in Japanese macaques and non-conceptive sexuality in humans. [ABSTRACT FROM AUTHOR]

The clock gene period (per) is a regulator of circadian rhythms but may also play a role in the regulation of ultradian rhythms, such as insect courtship. Males of the parasitoid wasp Nasonia vitripennis court females by performing series of head movements ('head-nods') and wing vibrations within repeated cycles. The pattern of cycle duration and head-nod number is species-specific and has a genetic basis. In this study, the possible involvement of per in regulating Nasonia courtship rhythms was investigated in a southern and northern European strain that differ in number and timing of courtship components. Knockdown of per via RNA interference (RNAi) resulted in a shortening of the circadian free running period (tau) in constant darkness (DD), and increased both the cycle duration and the number of head-nods per cycle in both strains. These results point at a role of per in the regulation of ultradian rhythms and male courtship behaviour of N. vitripennis and may contribute to resolving the controversy about the role of per in insect courtship behaviour. [ABSTRACT FROM AUTHOR]

In species with long-term pair bonds, such as zebra finches, evaluating the quality of potential mates is critically important. Courtship is an opportunity to evaluate information from dynamic behavioural cues. Personality traits, as stable individual differences in behaviour, could predict the quality of a potential mate. How might personality traits influence mate choice? We examined the influence of several personality traits, including exploration, aggression, and social preference, on pair formation in zebra finches. We provided birds with a variety of potential mates and allowed them to select a pair partner. Our semi-naturalistic mate choice paradigm allowed birds to observe social information over an extended period, simulating the challenges of social evaluation that birds encounter in the wild. We found that pairing is influenced by personality, with birds selecting mates similar to them in exploration. The partner's exploration score relative to their own was more important than the absolute exploration score. [ABSTRACT FROM AUTHOR]

Although male courtship displays have evolved primarily to sexually attract females, they also generate inadvertent public information that potentially reveals the courter's relative sexual attractiveness and the perceived quality and sexual receptivity of the female being courted to nearby eavesdropping male competitors, who in turn may use this information to bias their social partner choices. We tested this hypothesis by first presenting individual eavesdropping male guppies (Poecilia reticulata) the opportunity to simultaneously observe two demonstrator males whose courtship behaviour was manipulated experimentally to differ, following which we tested them for their preference to associate socially with either demonstrator males. Test males preferentially associated with the demonstrator male who they had previously observed courting a female over the other (non-courting) demonstrator. This social association preference was not expressed in the absence of a female to court. Our findings highlight the potential for sexual behaviour influencing male-male social associations in nature. [ABSTRACT FROM AUTHOR]

Courtship behaviour reflects characteristics of an animal's general biology, while also reflecting selective pressures specific to reproduction. Mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus) are sister species that differ in antipredator behaviour and sociality. We observed sympatric mule deer and white-tailed males to document their grouping patterns, courtship tactics, and aggressive interactions during the breeding season. Consistent with the hypothesis that courtship strategies reflect species differences in antipredator tactics and sociality, mule deer males were more likely than white-tailed males to tend females in multi male–multi female groups. White-tailed males almost exclusively tended females in isolated pairs and prevented other males from joining their groups. However, both species spent more time in isolated pairs as courtship advanced, likely to reduce competition. Our results enabled us to distinguish courtship behaviours that reflect contrasting antipredator tactics and sociality from courtship behaviours that reflect reproductive selective pressures that the species share. [ABSTRACT FROM AUTHOR]

Opportunities for studying platypus courtship and mating behaviours in the wild are limited due to the nocturnal and cryptic nature of this species. We report on platypus courtship and mating behaviour from a successful breeding program at Healesville Sanctuary, Victoria, in which platypuses were held as either breeding pairs or trios over seven years. Behaviour was recorded daily on infrared cameras resulting in over 80,000 h of footage that was analysed for activity periods, and courtship and mating behaviours including non-contact and contact courtship, mating and avoidance. Our aims were to describe and quantify courtship and mating interactions between males and females, and to determine if either sex controlled the initiation and continuation of the behaviours. From our observations, we describe a new courtship behaviour, non-contact courtship, which constituted the majority of all mating season interactions between males and females. The time between first and last appearance of a courtship and mating behaviour was 41.0 ± 6.6 days, with the females showing behavioural receptivity for 29.6 ± 5.1 days. Female platypuses used three evasive strategies in relation to approaches by males: avoidance, flight and resistance. Females controlled the duration of 79% of encounters using resistance. For the first time, two females were seen competing with each other over access to the male platypus in their enclosure and for nesting material. Time investment in courtship and mating behaviours was a poor indicator of receptivity and breeding success, and we suggest that breeding failure is more likely to be associated with failure of fertilisation, nest building, embryonic development or incubation. We describe how female platypuses demonstrate evasiveness and control of courtship and mating behaviours, and the importance of providing these opportunities in captivity to promote successful breeding. [ABSTRACT FROM AUTHOR]

Courtship-signalling theory often incorporates the assumption that males must consistently produce the highest-intensity displays they can achieve, thereby indicating their underlying quality to females. Contest-signalling theory, in contrast, assumes that flexible signal performance is routine. The two frameworks thereby suggest conflicting predictions about male flexibility when the same signal operates in both intrasexual and intersexual communication. Sexual competition often occurs within complex social environments where male displays can be received by potential mates, rivals, or both at once. In brown-headed cowbirds’ breeding flocks, for example, multiple males sometimes vie directly for a single female’s attention; at other times males have opportunities to sing to females without interference. We tested whether cowbirds vary the intensity of their signalling across contexts like these. We recorded songs from males courting females both with and without a male competitor in sight. We then played those recordings to solitary, naïve females in sound attenuation chambers, and also to a naïve aviary-housed flock. The songs males had produced when they could see their competitors were more attractive, eliciting more copulatory postures from naïve females and more approaches from birds in the flock. Results suggest high-intensity displays function within a larger, flexible signalling strategy in this species, and the varying audience composition that accompanies social complexity may demand flexible signalling even in classic display behaviours such as birdsong. [ABSTRACT FROM AUTHOR]

Experimental individuals are frequently marked with coloured tags for individual identification. Except for birds, the consequences of such artificial tagging on mate choice have been rarely investigated even though individuals often prefer naturally brightly coloured or symmetrically ornamented mates. We tested whether differently coloured Visible Implant Elastomer (VIE) tags influence female mate choice in rainbow kribs, Pelvicachromis pulcher. Females were allowed to simultaneously choose between a control and a VIE-marked male. The VIE-marked male carried two tags of the same colour (red, blue, green or white) set symmetrically or asymmetrically. Females did not show a preference for or avoidance of males carrying any of the colours compared to control males, no matter if the tags had been set symmetrically or asymmetrically. Although we found no discrimination for or against colour-tags, we highlight the importance of considering potential influences of colour-marks on mate choice in behavioural and evolutionary studies. [ABSTRACT FROM AUTHOR]

Male asses usually consist of two classes, social bachelors and solitary, territorial males. However, our observations of the Tibetan wild ass (Equus kiang) suggested a third class may exist. Unexpectedly, unidentified males were often found courting females within another male's territory. To test our hypothesis that a new social class existed, we compared 12 social behaviours among three putative groups. The third male-type spent less time herding and demonstrating flehmen, while spending more time retreating, trotting and in proximity of females, where they were more likely to engage in courtship and urine-marking. Based on increased time spent among females within other territories, the most courtship events, and minimal time invested in each courtship, they appear to employ 'sneaky' mating tactics. We discuss whether these 'transient' males are demonstrating an adaptive alternative mating strategy, or whether these behaviours result from a discrete developmental stage of bachelors unready to challenge a rival. [ABSTRACT FROM AUTHOR]

Differences in sexual signals among species are common, and may influence mate recognition and reproductive isolation. In scorpions, behavioural mechanisms and other sexual signals involved in mate selection and reproductive isolation have been scarcely studied. In this paper, we compare different male sexual signals between two distant populations of the scorpion Bothriurus bonariensis, one located in Uruguay and the other in Central Argentina. We compare sexual behaviours from intra-populations and inter-populations matings. In addition, we extent this comparison to the secreted compounds and morphology of the exocrine glands located on the dorsal side of the tel son in this species. Males of B. bonariensis performed stimulatory behaviours to the female with different frequency of occurrence and duration in the two populations. Chemical analyses of the glandular extracts showed that Uruguayan males present compounds which are absent in males of Argentinian population. In addition, we observed that in inter-population matings, stimulatory behaviours had intermediate patterns to intra-population matings. However, males failed to achieve a successful sperm transfer with females of different population. Mechanisms of sexual isolation between these two distant populations of B. bonariensis apparently seem to have evolved due to divergence in allopatry. The differences in stimulatory levels during courtship between the two populations studied here give evidence for an early behavioural divergence promoted by sexual selection. [ABSTRACT FROM AUTHOR]

Phenotypic flexibility is essential for organisms to respond to changing environments. Guppies experience light environments that alter their visibility to conspecifics and predators. We used guppies from populations with low rates of predation by fish, but which may be subject to avian predators, to test the hypotheses that conspicuous behaviors and the androgens that mediate them are reduced under high light, and that cortisol levels are increased under high light because the perceived risk is stressful. We found reduced courtship, potentially driven by the reduced female response to courtship, under high light. Aggression and testosterone levels were higher in the absence of females. We found elevated androgen and decreased cortisol levels following social interactions, but no relationship between hormones and behavior, and no influence of light level on hormones. We forward explanations for these results and advocate understanding the flexible response to light environments in a range of guppy populations. [ABSTRACT FROM AUTHOR]

Opioids are implicated in social attachments, but their role in avian pair bonds is not well understood. The present study tested the effects of naloxone, an opioid antagonist, on pairing using both a forced-choice and a mixed-sex aviary paradigm. First, three doses of naloxone were systemically administered in males using a repeated measures forced-choice design, partner preference formation was tested on the second day. Males treated with 20 mg/kg sang less undirected song. Males treated with 10 mg/kg of naloxone sang less to the familiar partner than when treated with saline and were less likely to form a partner preference than were other treatments. In females, 10 mg/kg of naloxone in a forced-choice paradigm increased preference for the unfamiliar over the familiar male. Finally, males and females were administered either naloxone (10 mg/kg) or saline in a mixed-sex aviary. In females, naloxone increased pairing behaviours, but had no other effects in either sex. Our findings suggest that the effects of naloxone on pairing-related behaviours are context-dependent; male-male competition may decrease the effects of naloxone on male song and a choice of mates may increase affiliation in females in a semi-naturalistic paradigm, and increase preferences for an unfamiliar partner in a forced-choice paradigm. Our findings highlight the importance of using multiple paradigms to test mechanisms of behaviour. These findings contribute to our understanding of the mechanisms of monogamous relationships and suggest that opioids play a role in male courtship, female affiliation and partner preferences in both sexes of zebra finches, but that context is important. [ABSTRACT FROM AUTHOR]

Male courtship behaviour towards choosy females often comprises elaborate displays that ad-dress multiple sensory channels. In bats, detailed quantitative descriptions of multimodal courtship displays are still fairly scarce, despite the taxon's speciose nature. We studied male courtship be-haviour in a polygynous Neotropical bat, Seba's short-tailed fruit bat Carollia perspicillata, by monitoring harem males in a captive colony. Courting male C. perspicillata performed stereotypic tactile, visual and acoustic displays. A courtship sequence, directed at one female at a time, lasted up to 120 s. During courtship, males approached females by brachiating or flying, hovered in front of them, pursued them on the wing, sniffed them and repeatedly poked the females with one or both folded wings; the latter behaviour was the most conspicuous male courtship display. Immediately before copulation, males wrapped their wings around the females and bit their necks. As acoustic display, courting male C. perspicillata produced highly variable, monosyllabic courtship trills. The species' vocal repertoire consisted of ten different social vocalisation types, three for benign inter-actions (courtship trills, wobbles, isolation calls), four for aggressive encounters (aggressive trills, down-sweeps, warbles, distress calls) and the remaining three for unknown behavioural contexts (V-shaped calls, flat down-sweeps, hooks). Courtship trills and aggressive trills were exclusively produced by males. We measured 245 courtship trills of five males and found statistical evidence for a strong individual signature which has the potential to facilitate female choice, mate recogni-tion or neighbour-stranger recognition among male competitors. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The function and relative importance of low-amplitude (quiet) acoustic signals remains a poorly understood aspect of animal communication. Research in songbirds has predominantly focused on the role of low-amplitude songs as reliable predictors of attack and signals of aggressive intent. However, many species of songbirds produce low-amplitude song in the presence of both male and female conspecifics, suggesting a broader range of functions beyond aggressive behavior. Male dark-eyed juncos (Junco hyemalis) produce two distinct types of low-amplitude song: (1) soft long-range song (LRS), which is a lower amplitude version of junco LRS, and (2) short-range song (SRS), which is substantially more complex and structurally distinct from LRS. SRS is also sung at two distinct tempos (slow and fast) and has been observed in both male- and female-directed contexts. In this study, we presented free-living male juncos with a caged male or female conspecific accompanied by playback of LRS, a female precopulatory trill, or slow SRS and quantified the songs elicited by each social condition. Males produced slow SRS only in response to a female conspecific paired with a precopulatory trill or slow SRS, never to a male, even when males were paired with slow SRS. Together these observations indicate that slow SRS is a female-directed song. In contrast, males produced both LRS and soft LRS in the presence of conspecifics of both sexes, which suggests that LRS may serve a similar function with respect to male and female receivers regardless of amplitude. These results highlight the importance of investigating the production of low-amplitude songs in both intra- and inter-sexual contexts and provide further evidence that in juncos, slow SRS functions in courtship. [ABSTRACT FROM AUTHOR]

Communication signals provide key information for conspecific recognition, mate choice and rival assessment. The painted goby Pomatoschistus pictus and the common goby P. microps are two closely-related sand goby species, often sympatric and with an overlapping breeding season. In this study we staged male-male and male-female interactions and compared visual, tactile and acoustic behaviour in both species. Sound production in the common goby is here accounted for the first time. We observed some differences in visual behaviour and a striking divergence in the use of tactile and acoustic communication during courtship and agonistic interactions. We further describe differences in drumming signals with social context in the painted goby. This study suggests a divergence in communication in two closely-related sand goby species and emphasizes the importance of further research concerning the role of multimodal communication in closelyrelated species. [ABSTRACT FROM AUTHOR]

Habituation, or the relatively permanent waning of a response as a result of repeated stimulation, is a form of behavioural plasticity that allows animals to filter out irrelevant stimuli and to focus selectively on important stimuli. Individuals that fail to habituate might be at a disadvantage if they continue to respond to irrelevant stimuli; therefore, habituation can have adaptive significance. In this study we compared rates of behaviour over time toward three different ecologically-relevant stimuli (food, a male intruder and a gravid female) in threespine sticklebacks (Gasterosteus aculeatus). We detected evidence for habituation to the stimuli, and males in this study were especially aggressive toward both male and female conspecifics. Although there were some clear temporal patterns that could be detected by looking at average behaviour, not all individuals behaved in the same 'average' way. We detected substantial inter-individual variation in behaviour toward all three stimuli, inter-individual variation in rates of habituation to both male and female conspecifics, but no evidence for correlations between behaviours across stimuli (behavioural syndromes). These results suggest that individual animals vary in rates of habituation, and prompt hypotheses about the causes and consequences of variation in rates of habituation. [ABSTRACT FROM AUTHOR]

In the peacock blenny (Salaria pavo) the reproductive behaviour is described to vary between two populations that differ in nest availability. At the Gulf of Trieste (GT), Italy, where nest availability is high, conventional sex roles are present and males adopting an alternative parasitic reproductive tactic are rare. Conversely, at Ria Formosa (RF), Portugal, where nest site availability is low, females are the courting sex and a high percentage of parasitic males occur. Laboratory experiments were used to study the degree of plasticity of the reproductive behaviours used by females and by the two male morphs in both populations. Nesting males were sequentially presented with a female and a female-like parasitic male and the reproductive behaviours of all fish were quantified. Under similar laboratory conditions, nesting males from both populations did not differ in sexual or agonistic displays towards females or parasitic males, showing that males from the sex-reversed population are also able to express significant levels of courtship. In contrast, females followed the typical population pattern, with females from RF courting nesting males more and more readily than females from GT. We hypothesised that apparent differences in behavioural plasticity between nesting males and females were a consequence of the perception of the presence of eggs in the nest. Nesting males from both populations received an empty nest during test trials and, thus, had to court females in order to receive a first spawn. On the other hand, females were probably unaware of the presence or absence of eggs when presented to the nesting male and assumed the population typical courtship profile. Interestingly, the parasitic males' behaviour towards the nesting male closely followed the displays of females from their own population; parasitic males from RF courted the nesting male with a high frequency of female-like displays while parasitic males from GT failed to exhibit female-like courtship behaviour. Taken together, the results suggest that S. pavo presents high levels of plasticity in reproductive behaviours and that these may underlie the interpopulation differences in behaviour reported for the species. Additionally, the results also suggest that the parasitic male reproductive tactic at GT is not based on female-mimicry. [ABSTRACT FROM AUTHOR]

Our study investigated the effects of winning, losing, or not participating in a fight on pairing and mating behaviour in a cichlid fish, the blockhead (Steatocranus casuarius). In this study, males that won a fight were significantly more successful at pairing and reproducing than either males that lost a fight or males that had not fought. Males' and females' behaviour also differed depending on males' fighting experience. Winning males spent significantly more time engaged in courtship behaviours such as quivering next to a female compared to males that lost fights or did not fight. Also, winning males more often used moderately aggressive behaviours such as tail beating when with their potential mates. Highly aggressive acts like biting were not correlated with pairing success; such acts were common in no-fight males but infrequent in both winner and loser treatments. Females with winning males were the most likely to show appeasement behaviour such as tilting when approached by the male, and females with males that had not fought were most likely to bite their males, which could have been either a response to or a result of the higher levels of biting displayed by those males. [ABSTRACT FROM AUTHOR]

Male pigeons exhibit robust courtship to the head of a female, but not so much to the body. The specific features in the female head which are critical for triggering courtship from males remain unclear. We examined this issue by studying preference behaviour of male pigeons between a pair of photographic images of female conspecifics: a series of normal female faces and a series of digitally altered facial features. Preference was determined by measuring the duration of male courtship 'coo' responses near each of these images. Males preferred intact females compared to those missing the eyes and beak. They also responded less when only the eyes and beak were visible without the head, suggesting that these local features were important, yet more effective when embedded in the context of the head than when they were not. Enlarging or removing the beak had a significant impact on preference, whereas manipulating the eyes had a weaker effect. Finally, males exhibited no preference between normal females and those that had spatially rearranged eyes and beak. These results suggest that pigeons naturally attend to the local features of the head, but not to the spatial configuration, for conspecific recognition. [ABSTRACT FROM AUTHOR]

Crickets in the family Gryllidae are well known for their elaborate mating behaviors; however, behavior of the subfamily Trigonidiinae is poorly understood. A large portion of this clade is endemic to Hawaii, including three genera: Trigonidium, Laupala and Prolaupala. The only Hawaiian genus that has been studied is Laupala, which exhibits unusual nuptial feeding in the form of spermless 'micro' spermatophores. Microspermatophore donation has been suggested to increase sperm transfer, constituting a novel mechanism of mating effort in crickets. We observed mating from representatives of each genus to investigate behavioral diversity and reconstruct character state evolution. We found that Prolaupala species produce microspermatophores during a behavioral sequence very similar to Laupala. Trigonidium do not produce microspermatophores, but exhibit other behavioral strategies that likely function to improve insemination, such as prolonged copulation and post-copulatory guarding. We also observed spermatophore and copulation characteristics that were previously considered unique to other gryllids. Behavioral diversity among the Hawaiian fauna reflects the evolutionarily labile nature of gryllid mating behavior and convergence of behavioral strategies in response to sexual selection. Furthermore, our results suggest that microspermatophore donation may be a common mating effort strategy within Trigonidiinae. [ABSTRACT FROM AUTHOR]

Natural and sexual selection often act in opposing directions, forcing individuals to prioritize activities necessary for survival with those required for reproduction. We examined the interaction of natural and sexual selection pressures on the behaviour of beaugregory damselfish, Stegastes leucostictus, by presenting territorial males with an egg predator and either a male or female conspecific, requiring males to prioritize brood defense with either courtship or intra-sexual competition. By measuring the time spent near stimuli, we examined the influence of several factors, including stimuli type, variation in predator number, and the presence of eggs in a nest site. Generally, males spent more time with conspecific stimuli than egg predators, suggesting that the sexual selection pressures of deterring rivals and attracting mates outweigh the natural selection pressure to engage in brood defense. This decision was affected by the sex of the conspecific presented, the presence of eggs in a male's territory, and a number of interactions of these factors, indicating that male damselfish consider multiple factors before investing in certain types and intensities of behaviours. Furthermore, observations of behaviours associated with courtship and intrasexual aggression show that a natural selection pressure impacts intra- and inter-sexually selected behaviours differently in this system. [ABSTRACT FROM AUTHOR]

Female spotted hyenas (Crocuta crocuta) are larger and more aggressive than males, and their genitalia are heavily 'masculinized'. These odd traits in females pose unusual challenges for males during courtship and copulation. Here our goals were to describe and quantify the behavior patterns involved in courtship and copulation in Crocuta, and determine whether rates of affiliative behavior directed toward females by males vary with female age, social rank, or time to conception. We also inquired whether consort formation with a particular female was necessary for a male to sire that female's cubs. Behavioral observations and paternity data based on 12 microsatellite loci were collected over 11 years from free-ranging hyenas in Kenya. Several of the courtship displays exhibited by male hyenas differed from those found in other carnivores, and appeared to reflect intense motivational conflict between tendencies to approach and flee from females. Most male advances were either ignored by females or elicited aggression from females toward males. Rates of male affiliative behavior toward females peaked around the time of conception. Although males behaved similarly toward young and old females in the highest social rank category, males directed more affiliative behavior toward older than younger females that were mid- and low-ranking. Multiple short mounts usually preceded a long mount, but intromission and ejaculation appeared to occur only during long mounts. Female receptivity was indicated by inhibited aggression toward the male and assumption of a distinctive receptive stance. The only behavior indicative of female proceptivity was following of the male by the female in mating contexts. Some males who sired cubs formed consortships with females whereas others did not, suggesting that individual male hyenas may adopt alternative reproductive tactics to attract and acquire mates. Our results also suggest that low fertility may be an important cost of female virilization in this species. [ABSTRACT FROM AUTHOR]

Food sharing in birds occurs largely in the context of parental care and courtship. Previous studies found that juvenile jackdaws demonstrate high levels of active giving outside these contexts in the 3 months following nest dispersal. The function of this behaviour is not understood, although it seemed compatible with hypotheses of mutualism (both participants benefit), reciprocity and harassment avoidance. We propose a new functional explanation for active giving in this species, namely facilitating the formation of social bonds. Captive juvenile jackdaws actively gave 2.5% of temporarily available food items and objects to peers, irrespective of sex and kinship. Active giving accounted for 43.7% of all food transfers. Donors advertised food and objects through a distinctive display and initiated active giving more than recipients. The direction of giving was initially unfocused, but became selective until each donor predominantly gave to one recipient and affiliative relationships were formed. We conclude that food-sharing may be an integral part of jackdaw ontogeny which allows juveniles to explore their social environment and facilitates the formation of affiliative relationships when family bonds dissolve. We also suggest that the ritualised food offer display may signal the 'collaborative intent' of the donor and serve to attract potential partners/mates. [ABSTRACT FROM AUTHOR]

We describe the nocturnal courtship songs of male dwarf stonebashers, Pollimyrus castelnaui, from the Okavango River and its inland delta. We examined the question of whether the songs are sufficiently differentiated from those of its parapatric sibling species, the only recently discovered P. marianne from the Upper Zambezi River, to form a potential cue for mate choice. Both species vocalised two sound types in courtship, the moan and the grunt, which they combined into long songs in similar fashion. However, one sound type was clearly differentiated: while P. castelnaui moans were of a husky quality and composed of three or four broadband formants, P. marianne moans were more tonal, with a single spectral line dominating the first and any higher formants (and a smaller bandwidth BW-10 dB for the dominant frequency of the first formant). Moan and Grunt Duration and the moan Pulse Group Period (mPGP) were longer, and the latter more variable, in P. castelnaui compared to P. marianne (range of mPGP: 10-30 ms in P. castelnaui, 7-16.7 ms in P. marianne). P. castelnaui grunts were of longer duration and composed of more pulses than those of P. marianne. A single male from the contact zone between the Okavango and the Zambezi, the lower Kwando River, resembled P. castelnaui in moan BW-10 dB but P. marianne in Moan Duration and mPGP. Both southern African species thus vocalise in a species-specific fashion. Since in both species several characteristics of both moans and grunts show high between- and low within-male variability, mate choice may be selective for individual high-quality males characterised by acoustic features. [ABSTRACT FROM AUTHOR]

It is understood that mate choice, competition, and sex differences produced by sexual selection underlie behavior, but few studies focus on their interactions within a system to understand how they shape behavior. Here, using the monogamous convict cichlid, Archocentrus nigrofasciatus, we examined the mate choice process of males and females in the presence of intrasexual competition. We compared and contrasted patterns reported in a previous study exploring this process in the absence of competition by using the same methodological paradigm. Specifically, two individuals (i.e., the competitors) were presented with a choice of two alternative, visually and tactilely isolated, mates and observed until one competitor (i.e., the primary competitor) spawned with one of the potential mates (i.e., the accepted mate). This was done for males and females separately. Both sexes spent more time with their mates while attacking and inhibiting the courtship of the other competitor (i.e., the secondary competitor). Only females expressed this time preference in the absence of competition (Santangelo & Itzkowtiz, 2004), but both sexes visited accepted mates more in the presence of competition. These results suggest competition causes the adoption of a mate guarding tactic. Males exhibited more differences than females with the addition of competition suggesting that male mate choice patterns are more labile than females. We attribute this to the ability of males to be bigamous and the adoption of different strategies based on the level of male-male competition. Courtship was not affected by competition for either sex, however the courtship of secondary individuals did appear to be influenced by primary individuals. Competition did not eliminate a searcher's continuous assessment of potential mates, yet it was conducted to a lesser degree. Thus, mate guarding is an important strategy that must be balanced with an individual's inclination to continuously assess based on present competition levels. [ABSTRACT FROM AUTHOR]

Although the individual elements of stickleback behaviour are well known, to date a robust investigation of the temporal cycling of aggressive, courtship and parental behaviour during the breeding cycle has been undertaken in only one species, the threespine stickleback, Gasterosteus aculeatus. In order to understand the evolution of behaviour in this fascinating group of fishes, comparative studies conducted upon other members of the Gasterosteidae are necessary. We thus documented the cyclic changes and structure of sixteen agonistic, parental and courtship displays across the breeding cycle for a population of brook sticklebacks, Culaea inconstans, from Nebraska and compared it to the temporal cycling of reproductive behaviour in the threespine. Our results indicate that in the brook stickleback: (1) aggressive behaviour varies temporally in response to a male, but not a female, intruder. (2) During those phases wherein the young are nest bound, aggressive and parental elements are negatively correlated. (3) The location of the focal fish within the tank during the trial is an accurate indicator of his primary motivation and (4), a sex specific differential response to intruding fish is apparent only during the courtship interval. The temporal structure of reproductive behaviour in the brook stickleback mirrors that of the threespine stickleback in three respects: (1) aggressive motivation across the breeding cycle exhibits a U-shaped distribution, with peak levels of aggression occurring in the nest-building stage and final days of parental care. (2) During the courtship phase sexual motivation supercedes aggression in response to the presence of a nuptially coloured female and (3), the pattern of parental fanning shows an inverted U-shaped distribution with peak frequencies coinciding with the hatching of the eggs. [ABSTRACT FROM AUTHOR]

We investigated the mechanism by which courting males of the desert spider, Agelenopsis aperta, induce a quiescent state in females. We experimentally induced quiescence in two ways. First, we suspended courting males below females who were housed within netted isolation chambers. Second, we exposed females to air passed over a homogenate of male tissue. Both treatments induced a quiescent state in test females, supporting the hypothesis that an airborne chemical emitted by males elicits female quiescence. Additional tests involving the female isolation chamber indicated that this molecule has an effective range of about 3 cm, and that male drumming of the palpal appendages during courtship may direct the pheromone plume towards the female. [ABSTRACT FROM AUTHOR]

Individual threespine sticklebacks (Gasterosteus aculeatus) presented with a choice of two stimuli (dummies or video images) that simulate prospective mates show a preference but nevertheless allocate a substantial proportion of their courtship effort to the less preferred one. The evidence presented here reveals additionally that mating preferences of male and female stickleback are expressed more strongly as their overall courtship response increases. This suggests that a more sexually aroused fish attends more to cues relevant to mate choice and is more selective of mates than less aroused fish are. This effect is likely to be mediated by a central process and could have significant impact on mate choice and sexual selection, at least in situations where prospective mates are encountered simultaneously. [ABSTRACT FROM AUTHOR]

Compared to polygynous species, monogamous males and females are considered more similar in their mate choosiness, yet few studies have explored the mate selection process between the sexes. Here, we examined this mate selection process in the monogamous convict cichlid, Archocentrus nigrofasciatus. We presented an individual (i.e. the selector) of each sex with a choice of two alternative, visually and tactilely isolated, mates. Tanks were video taped each day until the selector fish spawned with one of the potential mates (i.e. the accepted mate). The number of visits, length of visits, and courtship interactions were recorded. Selecting females spent significantly more time with accepted versus rejected males (i.e. females expressed a time-based preference for their chosen males), but there was no significant difference in the number of visits made to either male. Selecting females did not court accepted and rejected males differently, but rejected males courted at a significantly higher rate than did accepted males. Although selecting females expressed a time-based preference for accepted males, they continued to visit and court rejected males throughout the mate choice process; thus females did not terminate their selection process until they spawned. In contrast to selecting females, selecting males did not spend a significantly different amount of time with accepted and rejected females while visiting both females equally. Furthermore, selecting males courted accepted females significantly more than they courted rejected females. Thus, males expressed their mate preferences through courtship whereas females expressed them through time spent. Males also courted more than females. Many of these sex differences curiously resemble those of a polygynous social system, which we suggest perhaps indicates polygynous ancestral origins. [ABSTRACT FROM AUTHOR]

Playback experiments were conducted with 4 week old Ile-de-France lambs (Ovis aries) to assess the role of auditory cues in social discrimination. After being habituated to the test enclosure, lambs were individually exposed to bleats from two stimulus individuals. Twin lambs were tested with recorded bleats of their sibling versus an unfamiliar agemate and single lambs with bleats of a familiar agemate versus an unfamiliar lamb. Lambs responded more frequently to the bleats of their sibling (for twin lambs) or of a familiar agemate (for single lambs) than to those of an unfamiliar lamb. Such discriminative responses to the bleats of familiar twins and non-kin lambs suggest that vocalizations may be a sufficient basis for social recognition. Acoustic analyses of the playback bleats revealed significant differences between the signals from the different stimulus lambs and suggest that fundamental frequency may be an important parameter of lambs' individual vocal signatures. [ABSTRACT FROM AUTHOR]

Using the permanently territorial beaugregory damselfish (Stegastes leucostictus), we examined behavioral differences between neighbors and how they relate to territory quality, male size, and social interactions. We manipulated territory quality by replacing some male's poor quality natural breeding sites with artificial sites. These artificial sites were known to rapidly increase a male's reproductive success. Three types of paired neighbors were tested: both males with high quality artificial sites (Group I); both neighbors with low quality natural sites (Group II); one male with a low quality natural site and his neighbor with a high quality artificial site (Group III). Because neighbors rarely interact, we stimulated interactions by placing a bottled male or a bottled female midway between the two breeding sites. The area between the 2 sites was rarely patrolled by either neighbor and we judged them to be outside of either male's territory. Although we found that both neighbors were in close proximity to each other while they simultaneously attacked a bottled male or courted a bottled female, the neighbors rarely interacted. Without one neighbor aggressively dominating the other neighbor, the neighbor that attacked or courted the bottled animal most intensively was termed 'dominant.' For pairs where both neighbors defended sites of similar quality (Group I and II), dominance was not related to male size. Reproductive success was only measured for Group I (both males with artificial sites) and relative reproductive success was not related to dominance. For heterogeneous pairs (Group III), dominance was related to territory quality (the male given the artificial site was always dominant when compared to his neighbor) but not male size. Irrespective of pair type (Groups I, II, or III), there was no inter-group differences in behavior among the dominants or among the subordinates. With the removal of the dominant individual, the remaining subordinates increased their aggressiveness toward bottled males and resembled the dominant individuals that were removed. Removing subordinate individuals caused no change in the behavior of remaining dominant individuals. Thus, the dominant males of all group types appeared to suppress the behavior of subordinates. We speculate that when neighbors have similar sites (Groups I and II), their past social interactions may be responsible for the development of the initial dominant-subordinate relationship. However, this dominant-subordinate relationship can be reversed by giving the subordinate male a higher quality breeding site ( i.e . Group III). We found no evidence that a subordinate's reproductive success was influenced by his more dominant neighbor and we speculate that it may influence his ability to secure a breeding site. [ABSTRACT FROM AUTHOR]

Transmission of acoustic signals through the habitat modifies the signals and may thus influence their use in communication. We investigated the transmission of five different types of whitethroat (Sylvia communis) vocalisations, three types of song and two calls. Typical examples were broadcast and re-recorded in a whitethroat habitat with hedgerows and open meadow. We used a complete factorial design with speaker and microphone placed in different natural sender and receiver positions including high perches and song flights. Sound degradation was quantified in terms of signal-to-noise ratio, excess attenuation, tail-to-signal ratio and blur ratio. The results suggest that sound degradation generally increased with distance along a hedgerow, which means that birds here potentially may use degradation in assessing the distance to a vocalising individual. This is unlike the open meadow where the change in degradation with distance was negligible. Surprisingly, song flight relative to perched singing seems not to facilitate transmission of own vocalisations or perception of vocalisations from other individuals, and song flight vocalisations do not transmit differently from other types of vocalisations during song flights. One purpose of song flights might therefore be visual location by potential receivers and surveillance by the territory owner. Source level and degradation differed between the five types of vocalisations in accordance with their functions. Motif song and song flight songs used in attraction of females and/or deterrence of males could transmit through neighbouring territories, whereas the calls and the courtship diving song where a specific individual within or near the territory is addressed had relatively short communication ranges. [ABSTRACT FROM AUTHOR]

Previously, we investigated courtship behaviour of bidirectional, interspecific hybrid males of two species of Nasonia (Beukeboom & van den Assem, 2001). Characteristics of the displays were intermediate between those of the parental species, but at the same time were biased towards the paternal side. Due to the haplodiploid sex determination system of the Hymenoptera, the nearest male parent of the haploid (hence, fatherless) Nasonia males are their grandfather. Therefore, we have called this bias the 'grandfather effect'. In the present paper, we investigate one of the possible causes of the 'grandfather effect': nucleocytoplasmic interaction. In interspecific hybrids, the paternally donated nuclear genes must operate in an 'alien' environment: the maternal (heterospecific) cytoplasm. Adverse effects may prevail in this situation, and result in a biased gene transmission (although to the maternal side). With introgression techniques and subsequent hybridisation of introgressed lines, we constructed male progeny in which paternally contributed nuclear genes are conspecific with the maternal cytoplasm. Courtship of these males provide a test of the interaction hypothesis. Because our results show a persistence of the 'grandfather effect', a simple nucleo-cytoplasmic interaction seems an unlikely explanation of the phenomenon. [ABSTRACT FROM AUTHOR]

Macroevolutionary analysis of three components in the stickleback breeding system, male/female nuptial colouration, male/female courtship and male lead/female follow to the nest revealed that: (i) a change in the male lead is always coupled with a change in the female follow, although there is no correlation between changes in particular components of the leadfollow system; (ii) a change in male courtship is coupled with a change in female courtship in all taxa but Gasterosteus and Hypoptychus. Once again, there is no correlation between changes in particular courtship components except for a possible coupling of 'male pummel' and 'female sink to the substrate'; and (iii) there is no correlation between the diversification of the male and female nuptial colour signals. These different patterns of macroevolutionary co-origination and co-diversification interact to produce unique and reliable species and sex-specific signals at the beginning of courtship + tightly coupled signals involved in coordination between spawning partners at the final stages of courtship. In order to explain the preceding macroevolutionary patterns, we now need to delineate the genetic basis for the traits in each behavioural system. [ABSTRACT FROM AUTHOR]

In order to achieve copulation, a male snake must align his body in the same direction as his mate. This may not be a trivial problem in an elongate limbless animal, especially when the male is much smaller than the female (and hence, his head is far from hers) and when she is simultaneously being courted by many other males (so that much of her body is not visible). This is exactly the situation experienced by red-sided gartersnakes (Thamnophis sirtalis parietalis) at communal dens in Manitoba. To clarify this question, we modified cues available to males by manipulating various attributes of females (direction of movement, presence of head and tail, concentration of sex pheromones, etc.). Male alignment during courtship does not depend on the visual stimulus provided by the female′s head or tail. Instead, male alignment is influenced by the female′s direction of movement, and by pheromonal stimuli from her skin. We suggest that courting male snakes obtain directional information via their characteristic 'chin-pressing′ behaviour. By pressing firmly on each scale with his chin as he passes over it, a male moving anteriorly (but not posteriorly) along the female′s body will open a small gap between that scale and the next most anterior one. This gap enables his tongue-tips to penetrate more easily towards the scale-hinge area (overlain by the more anterior scale) where sex pheromones are concentrated. Thus, the direction of scale overlap provides pheromonal as well as physical cues that permit males to align correctly for copulation. [ABSTRACT FROM AUTHOR]

To study the influence of testosterone (T) on crowing in male Japanese quails, we combined hormonal and photoperiod manipulations of circulating androgens with a detailed analysis of the acoustic parameters of crows and of male courtship patterns. The structure of crowing was directly affected by T: high-androgen males uttered longer and lower-pitched calls than the others, call rate at dawn being related to androgens by a minimum threshold function. High- and low-callers, two consistent categories over many days, differed in their sexual performance: high-callers performed more courtship than low-callers, but there was no difference in attempted mating. Crowing is discussed as a potential target of sexual selection because, like a song, it is androgen-dependent, highly variable among individuals, and plastic in its structure at the beginning of the reproductive season. [ABSTRACT FROM AUTHOR]