Courtship Frequency Research Articles

Male southern water skinks (Eulamprus heatwolei) use both visual and chemical cues to detect female sexual receptivity

A wide range of organisms use chemical and visual cues in mate attraction and courtship; however, chemical discrimination relevant to reproduction and the interplay between these two types of communication are poorly understood in reptiles. We experimentally tested the ability of male Eulamprus heatwolei, a scincoid lizard, to discriminate between sexually receptive and non-receptive females in two ways. First, we conducted 155 staged encounters between males and females over 29 days to determine the start and the duration of the female receptive period based on the date of copulations. These data suggest that the receptive period lasted for approximately 7 days in late October under controlled laboratory conditions. We also recorded 6,330 individual male and female behaviours during these trials to evaluate the frequency of female courtship and rejection behaviours and the intensity of male courtship behaviour. Female courtship increased sharply during the receptive period and then diminished. The disparity between female courtship behaviours and female rejection behaviours was greatest during the receptive period. Male courtship intensity increased sharply prior to the receptive period, peaked during the receptive period and thereafter declined rapidly. To determine if males were using visual cues, chemical cues or both from females, we conducted an experiment during and after the receptive period wherein male lizards were presented with a choice of two retreat sites treated either with the odour of large sexually receptive females, odour of small sexually non-receptive females or no odour (control). Males preferred the scent of females over the odourless control, and analysis using a special form of a generalized linear model, the Bradley–Terry model, showed a clear order of retreat site preferences, with large sexually receptive females favoured over small non-receptive females over the odourless control. We speculate that males use vision to find females and then use their chemosensory ability to chemically evaluate female sexual receptivity once the pair are in close proximity.

Do male birds intercept and use rival courtship calls to adjust paternity protection behaviours?

We tested whether male rock sparrows (Petronia petronia) change behaviours directed at their females when played back courtship display calls simulating a potential cuckolding event in the vicinity of their nests. We compared the behaviour of males before, during and after such playback with the behaviour of males who received a control playback, territorial song. After playback of courtship display calls male rock sparrows increased the frequency of courtship displays directed towards their mate, as predicted, but not mate guarding. These results illustrate the interplay of reproductive and communication strategies, and extend our knowledge of how the social environment can affect within-pair dynamics.

Male alternative mating behaviour depending on tail length of the guppy, Poecilia reticulata

Male guppies, Poecilia reticulata, exhibit two distinct types of mating behaviour, i.e., courting females for solicited copulation and sneaking behaviour for forced copulation. It is known that the frequency of these alternative mating behaviours is affected by environmental, genetic and morphological factors. We examined the influence of male tail (caudal fin) length on the frequency of these two types of mating behaviour. Female orient responses to courting males increased according to male courtship frequency and did not differ between males with longer and shorter tails. In further mating interactions, however, females showed glide responses much more frequently to displaying males with shorter tails than to those with longer tails. Males with shorter tails performed courtships more frequently than males with longer tails. Males with longer tails attempted sneaking (gonopodial thrusting) more often than those with shorter tails. These results indicate that male tail length determines the frequency of these alternative mating behaviour in the guppy. Assuming male long tails to be a deceptive tactic to attract females, the greater frequency of sneaking behaviour by males with longer tails to unreceptive females should be adaptive.

Sexual selection favours small and symmetric males in the polygynous greater sac-winged bat Saccopteryx bilineata (Emballonuridae, Chiroptera)

We investigated how morphological traits of territorial males in the polygynous bat Saccopteryx bilineata were related to their reproductive success. Because of the frequency of aerial courtship displays and defence manoeuvres, and the high energetic costs of flight, we expected small and symmetric males to be better able to court females on the wing and to monopolize copulations with females in their harems. We predicted that small and symmetric males would sire more offspring within the colony and a larger portion of the young born within their harem than large or asymmetric males. We measured size and fluctuating asymmetry of 21 territorial males and analysed their reproductive success in 6 offspring cohorts (n=209 juveniles) using 11 microsatellite loci. As predicted, small and symmetric males had, on average, a higher reproductive success in the colony than large and asymmetric males. The percentage of young sired by males within their harem increased as males decreased in size, but was not influenced by fluctuating asymmetry. As fluctuating asymmetry of males correlated with their reproductive success within the colony but not within their harems, we infer that fluctuating asymmetry is probably related to female choice, whereas male size is probably important for harem defence on the wing.

Wing morph-related differences in the pattern of mating activity in a flightless bug, Pyrrhocoris apterus (L.) (Heteroptera)

Summary The mating activity of the long-winged (macropterous) and short-winged (brachypterous) adult males and females from a temperate population (Czech Republic) of the firebug Pyrrhocoris apterus (L.) was studied during the first 14 days of adult life under constant laboratory conditions. The study showed that macropterous pairs copulated almost three times less frequently than the brachypterous pairs. The mean inter-copulation period was significantly longer in macropterous females than in brachypterous ones. Despite the fact that there was no significant difference between the total courtship frequencies of macropterous and brachypterous males, the mean duration of the inter-mating period was significantly shorter in brachypterous males than in macropterous ones, which indicates higher mating vigour of the former. Thus, the lower mating propensity of macropterous pairs was mainly due to lowered receptivity of females and in some extent to lowered mating vigour of males. The courtships of males and copulations of pairs of both wing morphs occurred predominantly throughout the photophase. The mean (peak) time of courtship and copulation activities of brachypterous pairs occurred at about 17:30 MET and 19:00 MET before the onset of the scotophase, respectively. In macropterous pairs the mean peak time of courtship and copulation occurred 2 h earlier. The study showed that the wing morph-related differences in mating activity characteristic for many flying wing-polymorphic insects are maintained also in insects whose all macropterous specimens have evolved flightlessness.

Male preference for female foot colour in the socially monogamous blue-footed booby, Sula nebouxii

Female ornaments are expected to evolve through sexual selection when male parental investment is high. Blue-footed boobies are socially monogamous seabirds with a long period of biparental care. Males and females have colourful feet that are displayed ostentatiously during courtship, both before and after pairing, and extrapair copulations are frequent. We manipulated the foot colour of paired females to test whether this trait influences male courting behaviour, used here as an index of male preferences. There were no differences in time spent at the courting site, frequency of female courtship or frequency of copulations of 11 control and 15 experimental pairs. Experimental females, which had duller feet, received less intra- and extrapair courtship, suggesting that foot colour influences female attractiveness and opportunities for extrapair interactions. Our results support the idea that female foot colour in the blue-footed booby is favoured by sexual selection through male preference.

A comparison of behavioural change in Drosophila during exposure to thermal stress

In order to understand how adaptive tolerance to stress has evolved, we compared related species and populations of Drosophila for a variety of fitness relevant traits while flies directly experienced the stress. Two main questions were addressed. First, how much variation exists in the frequency of both courtship and mating among D. melanogaster, D. simulans, and D. mojavensis when each are exposed to a range of temperatures? Second, how does variation in these same behaviours compare among four geographically isolated populations of D. mojavensis, a desert species with a well defined ecology? Our hierarchical study demonstrated that mating success under stress can vary as much between related species, such as D. melanogaster and D. simulans, as between the ecologically disparate pair, D. melanogaster and D. mojavensis. Strains of this latter desert species likewise varied in tolerance, with differences approaching the levels observed among species. The consequences of stress on male courtship differed markedly from those on female receptivity to courtship, as mating behaviours among species and among strains of D. mojavensis varied in subtle but significant ways. Finally, a comparison of variation in thermotolerance of F1 hybrids between the two most extreme D. mojavensis populations confirmed that genetic variation underlying traits such as survival or the ability to fly after heat stress is completely different. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 83, 197‐205.

REPRODUCTIVE COLORATION IN FEMALE COLLARED LIZARDS, CROTOPHYTUS COLLARIS, STIMULATES COURTSHIP BY MALES

Female-specific reproductive coloration is widespread among lizards, prompting several hypotheses to explain the possible function(s) of such coloration in females. I tested four of these hypotheses using observational and experimental field studies of free-ranging collared lizard females, Crotaphytus collaris, which develop orange markings on the lateral torso in association with the reproductive cycle. Orange markings did not appear to function for advertisement to female competitors because females rarely displayed their coloration during interactions with consexual competitors, and markings developed well before the occurrence of peak aggression among females. By contrast, females frequently displayed their lateral torso when courted by males. The number of displays given to courting males did not differ in females that had and those that had not yet developed orange markings, suggesting that female coloration does not function for sexual recognition in collared lizards. Females developed orange pigmentation while they matured their first clutches, and markings were maintained between and throughout the production and oviposition of the second and third clutches. Male courtship encounters with females having naturally developed markings were longer and involved more male displays than those with females that had not yet developed their coloration, suggesting that development of coloration by females functions to stimulate male courtship when females are receptive. To test this hypothesis, I established nine female pairs of size- and age-matched females that had early vitellogenic eggs, but had not yet developed reproductive pigmentation. Female pairs were each residents on the territories of nine different males. One female in each pair was painted with orange spots and bars to mimic the natural orange coloration and the other with light brown to match the natural background coloration of female C. collaris and mask naturally developed pigments. Males began courting orange-painted females within 2 h, and, on average, orange females were courted over five times more frequently than brown females. The difference in courtship frequency did not appear to result from males avoiding brown females because the average distance between males and females in the two treatment groups was similar. These results support the hypothesis that reproductive coloration in C. collaris females stimulates courtship rather than signaling rejection of courtship to males.

The Frequency and Timing of Courtship and Copulation in Blackbirds, Turdus Merula, Reflect Sperm Competition and Sexual Conflict

AbstractIn a long-term field study we estimated the number of copulations per pair in blackbirds at 24.2 in a single reproductive cycle. Thus it seems unlikely that the only function of copulation behaviour is just to guarantee fertilization. We considered three other hypotheses which might explain frequent pair copulation: (1) as an effect of sperm competition, (2) cooperation between pair members aiming at increasing joint production of offspring; or, (3) sexual conflict resulting in female manipulation of allocation of time and energy of the male. We found no positive correlation between the copulation frequency and reproductive performance, a result that essentially falsifies the cooperation hypothesis. Only two extra-pair copulations were recorded. However, attempts at forced extra-pair copulation were very common and a high pair copulation rate might have evolved in response to sperm competition. Alternately, relatively high copulation rate in the pre-fertile stage of the reproductive cycle and female control over timing and frequency of copulation (via solicitation of copulation and/or rejection of courtship by the male) also supports the sexual conflict scenario. We suggest that our findings support the idea that the female prolongs the period of sexual activity to induce her partner to guard her (which reduces sexual coercion from other males) and to monopolise his parental effort (the male while mate guarding cannot pursue extra-pair activity or search for better mating options).

Do Male Veiled Chameleons, Chamaeleo calyptratus, Adjust their Courtship Displays in Response to Female Reproductive Status?

Variation in male courtship behavior may be due to inherent differences among males or may arise from males adjusting their courtship displays according to female responsiveness. Female veiled chameleons, Chamaeleo calyptratus, exhibit two distinctive suites of body coloration and behavior patterns that vary according to receptive and non‐receptive stages of their reproductive cycle. We presented male chameleons with both receptive and non‐receptive females, and recorded differences in their mating frequency, courtship intensity and courtship behavior patterns. As expected, males were more likely to court and attempt mating with receptive females. Although fewer males courted non‐receptive females, their courtship displays were significantly longer than those directed towards receptive females. Males also adjusted the contents of their displays according to female reproductive condition. Certain behavior patterns were unique to courtship displays directed towards each class of females. Males exhibited the behavior pattern `head roll' only when paired with receptive females, and `chin rub' was displayed only during courtship of non‐receptive females. We hypothesize that these differences in male courtship frequency, intensity and content reflect differences in female reproductive value. Although males may benefit from mating with both receptive and non‐receptive females, the costs associated with courtship may depend on female responsiveness. Thus, males adjust their courtship tactics accordingly.

Male Reproductive Success in a Promiscuous Armoured Catfish Corydoras Aeneus (Callichthyidae)

Among a variety of fish mating systems, promiscuity with random-mating seems to be most prevalent. However, detailed studies of promiscuity have been rare due partly to the peculiar difficulty in examination of male mating and reproductive success in the random mating. Females of the armoured catfish Corydoras aeneus (no sexual dimorphism other than size of males > females) spawn 10–20 egg-clutches with multiple males at a time, but an entire egg clutch is inseminated by sperm of a single male. We studied mating system of this fish in aquarium. Males had neither mating territories nor monopolized females, never being aggressive against rival males. Evidence of female preference for certain male traits including size was not detected. Females mated a male in proportion to his relative courtship frequency among males. Courtship frequency was not related to male size, and male mating success was not different between small and large males. Clutch size and insemination rate were different neither between small and large males nor between frequently and less frequently courting males. Thus, the male reproductive success will not be related to the male size, but directly to courtship frequency, indicating the random mating in this fish. There seemed to be fecundity advantage with size in female, and the consequent sexual difference in energy allocation will be responsible to the sexual dimorphism. We also discuss the low male-GSI in this promiscuous fish in which sperm competition hardly occurred.

The effect of thermal stress on the mating behavior of three Drosophila species.

Selection may act on the weakest link in fitness to change how a species adapts to an environmental stress. For many species, this limitation may be reproduction. After adult Drosophila melanogaster, Drosophila simulans, and Drosophila mojavensis males were exposed to varying levels of thermal stress well below those that endanger life, courtship and mating frequency declined. The regression coefficients of both courtship and mating success did not differ significantly between D. melanogaster and D. simulans males. In contrast, significant differences were present between the two cosmopolitan species and D. mojavensis. Courtship frequency decreased at a much slower rate in D. mojavensis than in D. melanogaster and D. simulans, and while heat-stressed D. mojavensis males continued to court, many did not mate. In the cosmopolitan species, courting males almost always mated successfully. Courtship behaviors, including wing waving, were observed in D. mojavensis at temperatures that prohibited flight, while flight, courtship, and mating were knocked out simultaneously in D. melanogaster. One possible explanation for decreased flight ability and courtship success may be the reduced heat shock response in the flight muscle tissue because Hsp70 expression was lowest in the thoracic tissue of both D. melanogaster and D. mojavensis.

The Frequency and Function of Aquatic Courtship and Copulation in Least, Crested, Whiskered, and Parakeet Auklets

Least (Aethia pusilla), Crested (A. cristatella), Whiskered (A. pygmaea), and Parakeet Auklets (Cyclorrhynchus psittacula) all engage in aquatic courtship and copulation behavior. We quantified auklet sexual behavior at sea to obtain comparative information related to sexual selection and to evaluate why auklets choose this unusual location for mating. Auklet courtship involved a variety of stereotyped displays. Although similar courtship displays occurred both at the colony on land and at sea, copulation took place only on the sea. Courtship and copulation was frequently disrupted by extrapair males. Extrapair copulation attempts occurred in all species and apparently successful unforced extrapair copulations were observed in Least, Crested, and Whiskered Auklets, suggesting that sperm competition is a feature of their mating systems. Male birds risk water damage to their sperm if they mount their female partners at sea and cause their cloacas to become submerged during insemination. Male auklets, lacking an intromittent organ, achieved cloacal contact without mounting the female so that their cloacas remained unsubmerged. Males positioned themselves behind their partners and rapidly flapped their wings, creating lift to bring their cloacas up against their partner's cloacas, pushing upwards and ensuring insemination occurred away from the sea surface. Possible hypotheses to account for exclusively aquatic copulation include predation and sexual harassment avoidance, and female testing of males, but a definitive explanation for this phenomenon remains elusive.

Testosterone and mate choice in the dark-eyed junco

Investigations of the effects of testosterone on male mating effort have focused on behaviours associated with intra-sexual interactions. We tested whether testosterone may also affect male reproductive behaviour by mediating the intensity and frequency of male courtship. In two simultaneous choice experiments, we assessed the relative attractiveness of testosterone-implanted males, whose testosterone levels were manipulated to match naturally occurring spring peaks, and empty-implanted control males, whose testosterone levels were lower and resembled those of males caring for young. In both experiments, testosterone-males outperformed control-males, giving both more frequent and more exaggerated displays. Females showed a significant preference for the peak-testosterone males as measured by both female attendance and female courtship displays. We concluded that variation in testosterone can affect male attractiveness to females and thus male copulatory success. Thus, testosterone has the potential to mediate all aspects of male reproductive behaviour and may provide a mechanism through which males adjust their full range of breeding behaviours (i.e. inter-sexual as well as intra-sexual and parental behaviour) to fit their current status. In a second experiment, we tested the effect of oestradiol treatment on female mating preferences. No evidence was found that oestradiol changed the preferences of females.

Penile Erection: A Reflection of Sexual Arousal and Arousability in Male Chimpanzees

Nadler, R. D. and E. S. Bartlett. Penile erection: A reflection of sexual arousal and arousability in male chimpanzees. Physiol Behav 61(3) 425–432, 1997.—A study was conducted to determine if sexual motivation in male chimpanzees, defined by the two components, sexual arousal and arousability, could be quantified by measuring penile erection during laboratory pair-tests of sexual behavior. Sexual arousal, the momentary level of sexual excitation, was quantified by single measurements on a scale of penile erection. Sexual arousability, the propensity for arousal, was quantified by the rate of approach to full erection and by mean erection scores. Sexual arousability, as defined, was related to the frequency of male courtship displays, copulations, and ejaculations, which were highest at midcycle and positively correlated with a quantitative measure of female anogenital swelling. Sexual arousal was negatively correlated with continued exposure to the female and least variable during midcycle. These operational definitions of sexual motivation in the male chimpanzee facilitate comparative research in which analogous indexes of sexual motivation are required, such as when extrapolating from animal to human.

Male‐male Competition and Female Mate Choice through Courtship Display in the Territorial Damselfish Stegastes nigricans

AbstractBoth sexes of the herbivorous damselfish Stegastes nigricans maintain individual feeding territories. These territories are distributed contiguously, forming distinct colonies. Females visit male territories to spawn, and eggs are guarded by males until hatching. Male‐male competition and female mate choice were studied in two colonies of different size compositions. Only larger individuals bred in both colonies. Some males in the large colony, that were larger than the breeding males in the small colony, did not succeed in reproducing probably because of severe attacks by the larger males while courting. However, females did not choose large size among breeding males. The most important male characteristic in female choice was the frequency of courtship displays in both colonies. Females in the large colony chose males mainly on the basis of the frequency of displays conducted in the females' territories, whereas females in the small colony chose males on the basis of the frequency of displays conducted in the males' territories. This difference may be a result of the difference in colony size. The distances between females' and males' territories were much greater in the large colony, and, because females cannot see courtship displays conducted in distant male territories, males in the large colony may have had to visit female territories frequently in order to conduct courtship near the females.

Social Communication in the Madagascar Hissing Cockroach: Features of Male Courtship Hisses and a Comparison of Courtship and Agonistic Hisses

AbstractMale Madagascar hissing cockroaches (Gromphadorhina portentosa) produce acoustic sounds or 'hisses' during courtship interactions with females. G. portentosa males also hiss during agonistic interactions with other males. In this study we documented intra- and inter- individual variation in male courtship hisses, addressed the possible role of hissing as an indicator of male rank, size or mating success, and determined if individual males produce different hisses during courtship and agonistic interactions. We found inter-individual variation in courtship hisses in dominant frequency and duration. Within males, these characteristics of the courtship hiss were repeatable within a day. Characteristics of courtship hisses and mating success were not related to male rank. However, courtship hisses may convey information about the size of the male: larger males had longer, lower frequency hisses than smaller males. There was a trend for males that mated to be larger than males that did not mate. However, characteristics of the' courtship hiss were not significantly related to mating success after controlling for differences in male weight. Finally, we found that the dominant frequency and duration of courtship and agonistic hisses of males did not differ suggesting that males are using similar signals during both courtship and agonistic interactions. We interpret these results in light of the possible functions of hissing, male-male competition, and female discrimination during courtship interactions.

Intraspecific Variation in Courtship and Copulation Frequency: an Effect of Mismatch in Partner Attractiveness?

AbstractThe aim of this paper is to present a verbal theoretical model that could account for the among pair variability in courtship and copulation behaviour that occurs both during and after pair formation in socially monogamous species. We assume that copulation acts to prevent mate loss, by reducing the availability of an individual to other potential partners. Variation in copulation and courtship frequency then arises as a result of variation in the risk of mate loss. Because of the constraints on free or ideal choice, pairs will form in which it may be possible for one individual to improve upon the quality of its partner. In a mismatched pair it will pay the poorer quality mate to guard the higher quality individual and prevent it from leaving to pair with a better quality mate. The poor quality individual will therefore solicit copulations at a high frequency while it's partner may not always respond. We predict that high levels of courtship and solicitation will relate to a high risk of mate loss and that a lack of response by a partner will relate to the potential opportunities it has to improve on partner quality. Our thesis is that variation in mating behaviour arises as a result of any deviations from assortative mating that may exist in a population.

Multiple mating in a lekking bird: why do peahens mate with more than one male and with the same male more than once?

Approximately 50% of marked peahens (Pavo cristatus) mate more than once with lek males. Some females mate with more than one male, others copulate repeatedly with the same male. The frequency of courtship also shows marked variation. Some females repeatedly engage males in courtship interactions after they have succesfully copulated with them. The likelihood of mating with more than one male increases if a female first mates with a non-preferred (unsuccessful male). There is a non-significant tendency for females to copulate with a more successful male when remating. Peahens may mate with a non-preferred male first if they do not encounter a successful male during their initial period of choice, perhaps because the most successful male on a lek was courting another female and/or was defended by another female. There are more aggressive interactions between females in front of preferred males. Preferred males receive more repetitive courtship behaviour and repeated matings. Dominant females are more likely to engage in repetitive courtship and matings. The number of times a female initiates courtship on any one day increases with the number of other females actively courting males at a lek site on that day. We suggest that there is competition amongst females for access to preferred males and that dominant females try to monopolise these males by repeatedly engaging them in courtship interactions. We discuss the implications of these observations for the idea that female may gain directly from mate choice in a species where males contribute nothing but gametes to their offspring.

Male sexual signaling is defective in mutants of the apterous gene of Drosophila melanogaster.

The apterous (ap) gene of Drosophila melanogaster exhibits extreme pleiotrophy: its functioning is essential for life, normal wing structure, juvenile hormone production, female fertility, and normal development of female sexual receptivity. Four mutant ap alleles (ap4, ap56f, apc, and apblt) were characterized for three additional phenotypes: male mating success, courtship behavior, and immature male sex appeal (the ability of males to stimulate homosexual courtship). Mating success with mature wild-type virgin females is reduced in males mutant for the ap gene, the extreme case being ap4/ap4 males, which are behaviorally sterile. In ap mutants, nonwing courtship elements are qualitatively like those of ap+/ap+ males. However, the mean rate of nonwing courtship directed toward virgin wild-type females (i.e., the mean temporal frequency of these displays) is reduced in males homozygous for ap4, ap56f, or apc alleles. In contrast, the apblt allele makes for wild-type rates of nonwing courtship. Immature male sex appeal persists for at least 3 days in males homozygous for apc and, to a lesser extent, in ap56f or ap4 homozygotes; apblt/apblt and wild-type males lose immature male sex appeal after 1 day. All three male phenotypes map to the ap locus, which is therefore essential for the development of normal levels of male courtship and male mating success and for the timely loss of immature male sex appeal. For each phenotype, ap+ is dominant to ap alleles making for behavioral abnormalities, with a single exception (for rate of nonwing courtship, ap+/apc was low). For mating success and frequency of nonwing courtship, each allele pair exhibits at least partial complementation, except for ap4 and ap56f, which fail to complement. For immature male sex appeal, apc, ap4, and ap56f fall into the same complementation group. Juvenile hormone production is not correlated with effects on male reproductive behavior.