Male mating success and survival in the field with respect to size and courtship song characters inDrosophila littoralis andD. montana (Diptera: Drosophilidae)

We investigated the importance of male song and morphological characters to the male mating success in a two-year field study in natural populations ofD. littoralis andD. montana. We compared the properties of mating flies with those of a random male sample taken at the same time and place. InD. littoralis the male's size had no effect on his mating success, while inD. montana small males had a mating advantage in the field during the first study year. Females preferred males with short sound pulses in both species. We also examined the relationship between male morphological and song characters and viability by collecting male flies in late summer and comparing the means of male characters to those of overwintered flies the next spring. InD. littoralis male size had no effect on overwinter survival. InD. montana large flies survived better than small flies. In both species the shifts in song characters during the winter dormancy were opposite to those caused by sexual selection. Our results, accordingly, imply a possible balance between the forces of sexual and natural selection, which act in opposing directions on attractive male traits.     

The possibility of sex and nymph discrimination by the male cockroach,Nauphoeta cinerea

The possibility of sex and nymph discrimination by males was investigated in the cockroach,Nauphoeta cinerea (Olivier). A sexually mature male takes a courting position toward a sexually mature female when he comes into contact with her and recognizes her through antennal contact. In contrast, males often behave aggressively toward each other: they bite at each others; wings and/or legs, chase each other and antennate mutually. The male, however, does not show conspicuous behavior (mating behavior or aggressive behavior) toward nearby nymphs. The male produces audible sounds when he courts a sexually mature but non-receptive female who does not respond to his courtship behavior. We found that the male also stridulates after he repeatedly courts immature teneral females, males and (last-instar) nymphs. After the bodies of teneral insects are sclerotized, the male shows courship and stridulation behavior toward sexually mature but non-receptive females but not toward mature males and nymphs. At this stage the male begins to behave aggressively toward other post-teneral mature males. We think that the variability of the sexually mature male's behavior toward other conspecifics (courtship behavior toward female, aggressive behavior toward male and no conspicuous response toward nymph) results from the male's recognition of adult and nymph.     

Male Remating Behavior and Its Effect on Female Reproductive Fitness in Cnephasia jactatana Walker (Lepidoptera: Tortricidae)

Male remating behavior and its effect on the female reproductive fitness of a New Zealand leafroller, Cnephasia jactatana, were investigated in the laboratory. With a recovery period of at least 24 h between matings, most males were able to mate four times and only about 25% could mate six times during their lifespan. Only 5% of males managed to mate twice within 1 day. Mated males transferred 31–51% smaller spermatophores than virgin males. When mating with a mated male, the female was subject to a 20–51% and 23–51% reduction in fecundity and fertility, respectively. With the increasing number of matings her partner had achieved before mating with her, the female's fertility declined significantly faster than fecundity. Courtship period and mating duration remained similar regardless of the male's mating history but males required increasingly longer latency to start courtship display with the increasing number of matings achieved.     

Differences between the sexes in direction and duration of response to seeing a potential sex partner mate with another

We have shown previously that: (1) female Japanese quail, Coturnix japonica, increase and male Japanese quail decrease their tendencies to affiliate with potential sex partners after seeing them mate, and (2) in both sexes of quail, affiliative preferences and choice of a sex partner are highly correlated. Here we predict that because effects of a prior male's sperm on a second male's probability of fertilizing a female are relatively brief, a male's avoidance of whichever member of a pair of females he has seen mating should be transitory. Conversely, because female quail seek high-quality males as mates and quality is a relatively permanent characteristic, females' preferences between males should remain constant over time. We found, as predicted, that the durations of effects on affiliation of seeing a potential sex partner mate differed in male and female quail. Forty-eight hours after male quail saw a female mate, they no longer avoided her, whereas 48 h after female quail saw a male mate, his attractiveness remained enhanced. We conclude by suggesting that both the direction and the duration of responses of male and female Japanese quail to seeing a member of the other sex mating enhance the fitness of members of each sex. Copyright 2000 The Association for the Study of Animal Behaviour.     

Do males have a better chance of mating when the number of estrous females is equal to or greater than the males' ordinal rank? Testing the hypothesis in Japanese macaques

This study was designed to test the hypothesis that male primates in multi-male/multi-female social groups with a clear male dominance hierarchy have a better chance of mating when the number of estrous females is equal to or greater than, as opposed to less than, the males' ordinal rank. I studied a Japanese macaque (Macaca fuscata fuscata) troop during mating seasons from 1992 to 1995. The mean daily operational sex ratio (OSR; the number of estrous females per troop male), which was calculated on observation days, was 0.21, 1.9, 0.48, and 3.1 in 1992-1995, respectively. Overall, focal animal sampling of males yielded 118 male-day records. The male-day records for each male were divided into the two estrous female number conditions: 1) the male-day records when the number of estrous females was equal to or greater than the male's ordinal rank, and 2) the male-day records when the number of estrous females was less than the male's ordinal rank. In the 1993 and 1995 mating seasons, when the number of estrous females was equal to or greater than the ordinal rank of each male, all of the males were observed mating. Conversely, when the number of estrous females was less than the ordinal rank of some male, they were not observed mating in the 1992 and 1994 mating seasons. The percentage for each male across each male's total mating opportunity was <20% when the number of estrous females was less than the male's ordinal rank. By contrast, the percentage for each male across each male's total mating opportunity exceeded 45% when the number of estrous females was equal to or greater than the male's ordinal rank, except for one male. Of all the male-day records for males observed mating with ejaculation, 41 were obtained when the number of estrous females was equal to or greater than the male's rank; conversely, only three records were obtained when the number of estrous females was less than the male's ordinal rank. Therefore, it appears that males have a better chance of mating when the number of estrous females is equal to or greater than the males' ordinal rank, as opposed to when the number is less than their ordinal rank.     

Sexual dimorphism in relation to swarming and pair formation patterns in leptocerid caddisflies (Trichoptera: Leptoceridae)

North European Leptoceridae (Trichoptera) perform three types of swarming flight patterns: (1) swarming males of Athripsodesand Ceracleafly in horizontal zigzag patterns over the water surface, (2) the Mystacidesspp. perform vertical zigzag movements, and (3) the flight of males of Triaenodes unanimisMcLach. is a mixture of the horizontal and vertical zigzagging. Also three groups of pair formation behavior can be distinguished. In the first group, of Athripsodesand Ceraclea,the females fly into the male swarms, where they are grasped and carried to the riparian vegetation by the flying males with the females hanging upside-down in genitalia coupling. In the second group, a Mystacidesfemale is caught by a male, when approaching a swarm and both use their wings to fly in tandem to the shore where they copulate. In the third group, of Triaenodes bicolor(Curt.) and Oecetis lacustris(Curt.), the males fly searching for females sitting on aquatic plants and when a female is found the male lands and they copulate immediately while clinging to the plant. The different swarming and mating behaviors might have favored selection for three types of sexual dimorphism: (1) longer forewings in males than females in species which fly in copula, (2) larger eyes in males of the vertically zigzagging species, and (3) much smaller males in the group where males search for females sitting on aquatic plants. In the second group approaching females are detected by males before reaching the swarm and in the third group the female almost always mates with the male which is the first to find her. In conclusion, we suggest that females of Athripsodesand Ceracleahave a greater choice among swarming males than do females of Mystacides, T. bicolor,and O. Lacustris.     

The social and reproductive behavior of the eyed flounder,Bothus ocellatus,with notes on the spawning ofBothus lunatus andBothus ellipticus

Synopsis Observations of the Caribbean eyed flounder,Bothus ocellatus, were made during two field trips to Bonaire, Netherlands Antilles (January 1990, and December 1990 – January 1991) at depths from 3 to 6 meters. Data were collected by six scuba divers during 54 dives totaling 70 hours. Three mating groups were observed, each consisted of a male and 1 to 6 females. Each female had a distinct subunit within the male's territory. Courtship activity began about one hour before sunset and continued until sunset, when the male retired for the night. Both males and females retired into the sand at locations outside their daytime territory. Every day, males attempted to mate with each female individually within their territory. Spawning began with the male moving under the female who was resting on the sandy bottom. The pair then made a slow upward rise approximately 15 to 75 cm above the substrate, which culminated in a release of a cloud of gametes.Bothus lunatus andBothus ellipticus exhibited similar social organization toB. ocellatus, but differences in the spawning rise were observed. Intraspecific agonistic behavior was observed within males ofB. ocellatus andB. ellipticus.Senior author     

Courtship behavior of the mosquitoSabethes cyaneus (Diptera: Culicidae)

Unlike any other mosquito reported, Sabethes cyaneus(Fabricius) displays an elaborate courtship before and during copulation. A male approaches a female suspended from a horizontal stick, suspends himself in front of her as he grasps her folded wings, and proceeds with a series of discrete stereotyped behaviors that involve proboscis vibration and movement of iridescent blue paddles on his midlegs. The sequence of these behaviors is as follows: freeleg waving, swinging, copulation attempt, superficial coupling, waving, genital shift, waggling, and release. Insemination occurs after genital shift. The only overt reciprocation by the female is abdomen lowering during the male's swinging. Courtship is often unsuccessful, and males are usually rejected during freeleg waving. The relation between male performance and mating success remains obscure.     

Determinants of male mating success in a large group of Barbary macaques (Macaca sylvanus) at Affenberg Salem

Male mating activities in relation to the likelihood of ovulation and conception were studied in a large group of semifree-ranging Barbary macaques (Macaca sylvanus) during two successive mating seasons. In both mating seasons, adult males attained a significantly higher mating success than subadult males, and they monopolized high ranking females more effectively than low ranking females during the period when conception was most probable. Also, in both mating seasons male rank was significantly correlated with male mating success if all sexually mature males were included. Nevertheless, mating success was not a linear function of age or rank. In both mating seasons mating success of 5-year-old males was much higher than that of dominant but peripheralized 6- and 7-year-old males. Moreover, a significant correlation between rank and measures of mating success among adult males was found in the second but not in the first mating season. The results indicate that mating and, most probably, reproductive success of male Barbary macaques is dependent on the male's social position in the group, which is defined not only by the outcome of dyadic agonistic encounters but also by the ability to get a central position in the group, and on the stability of rank relations.     

Sex roles in the ghost moth Hepialus humuli (L.) and a review of mating in the Hepialidae (Lepidoptera)

Recently it has been found that female Lepidoptera belonging to diverse families actively court their males, rather than play a merely passive role. Male and female Hepialus humuli have been reported to come together in three different ways: (1) females are attracted to groups or ‘leks’ of white, hovering males by visual stimuli; (2) females are attracted to the males by olfactory-substances produced on the hind-tibial brushes of the males; (3) males are attracted to sedentary females by olfactory stimuli. During my study I observed H. humili males flying on a total of 21 nights in two different parts of England. The males hovered in groups for about 20 min each evening, starting and stopping their flights in synchrony. Timing depended on light intensity, northern moths flying later in the summer evenings than southern moths. I observed a total of 18 matings. Normally, a female from outside a male lek flew into the group and up to one of the males. This male then usually followed her to a settling position, where mating took place. In a few cases females touched males; in one case a female struck a male in the air so that both fell to the ground and were copulating when examined. Photographs of hovering males show that their hind tibial brushes are fully everted in flight. The organs are folded against the body when the moth is mating, at rest or dead. Whilst hovering, the males are apparently emitting pheromones which function as primary attractants, rather than as the aphrodisiacs of many other lepidopteran males. The mating behaviour of hepialids is reviewed. It is concluded that all studied hepialids which have male brush organs (some Hepialus and Oncopera, Sthenopis, Zenophassus) exhibit similar flight and mating behaviour: males hover, sit or loop back and forth on the spot in leks; females fly into male aggregations and mate there (although some published observations suggest otherwise). In contrast, hepialids such as Fraus, Oxycanus and other Hepialus that lack male brush organs have mating behaviour in which the males are the active partner, a more standard lepidopteran method. In view of the controversies surrounding mating in hepialids, future systematic and behavioural work on Hepialidae throughout the world will be worthwhile.     

Reproductive Success Associated with Territoriality, Sneaking, and Grouping in Male Rose Bitterlings, Rhodeus ocellatus (Pisces: Cyprinidae)

The spawning success of male rose bitterlings, Rhodeus ocellatus, adopting an alternative reproductive style, was estimated through behavioural data and electrophoretic paternal analyses in field observations and experiments. Three mating patterns were observed: territoriality, sneaking, and grouping. Mating patterns depended on a male's relative size and on local male density (the number of males around a spawning spot: a mussel). Spawning patterns (pair spawning, pair spawning with sneaker, and group spawning) varied with local male density. Time-budget data of the territorial males indicated a trade-off between chasing and courtship behaviour as local male density changed. Females deposited appoximately only 1 egg per egg-laying into the mussels. As a result of isozyme analysis, a minimum of 12% (two out of 17) of the offspring in the sample were found to have been fathered by sneaker males in pair spawning with sneaker. I scored through behavioural data the mating success per spawning for each pattern, on an individual basis. The average reproductive success per spawning for each pattern was: territorial (0.61), sneaking (0.31) and grouping (0.11), and thus the successes of the patterns were not equal. Accordingly, the alternative reproductive styles of male rose bitterlings are best interpreted as alternative phenotypes in a conditional behaviour.     

The Effect of Limb Loss on the Courtship and Mating Behavior of the Wolf Spider Pardosa milvina (Araneae: Lycosidae)

Limb loss is common in the wolf spider Pardosa milvina, appearing in nearly one third of adult males but occurring less frequently among adult females and juveniles. Since males wave their first pair of legs during courtship displays, the reproductive consequences of limb loss may be significant. We measured the courtship and mating effects of the loss of one, two, or four legs among adult male P. milvina. Missing one or two legs did not significantly reduce a male's ability to mate, but missing four legs was detrimental to mating success, reduced both courtship intensity and copulation duration, and increased cannibalism frequency. Results suggest behavioral flexibility in compensating for limited leg loss and a defensive function of the anteriormost legs to thwart female cannibalism attempts.     

Virgin male mating advantage in a primitive acoustic insect (Orthoptera: Haglidae)

Male reproductive behavior in the relict flightless haglid, Cyphoderris strepitans,entails the generation of sound signals and the provision of nuptial gifts to mates. These food gifts take two forms: (1) a gelatinous mass (spermatophylax) augmenting the spermatophore and (2) fleshy metathoracic wings adapted to be eaten. The female consumes a portion of the male's underwings during courtship and copulation and the spermatophylax afterward. The incidence of wing-feeding wounds can be used to monitor the mating success of field-caught males. If, when a male mates, he compromises his ability to provide subsequent nutritive gifts, females would benefit by mating with virgin rather than nonvirgin males. To test this, mating success of virgin and nonvirgin males was compared in a field population. Virgins were found to obtain more matings than explained by their numbers relative to nonvirgins in the population. We conclude that, having mated, a male is at a disadvantage, relative to his virgin competitors, in securing further matings.     

Sexual coercion does not exclude luring behavior in the climbing camel-spider <Emphasis Type="Italic">Oltacola chacoensis</Emphasis> (Arachnida,Solifugae, Ammotrechidae)

Sexual coercion in the form of forced copulation has been used as a typical example to illustrate the conflict of interests between females and males. Among arthropods, forced copulation has been reported for some groups of insects and crustaceans, but not for arachnids. In the present work, we analyse and describe the behavioral patterns of mating behavior of the climbing camel-spider, Oltacola chacoensis, relating it to relevant morphological features, In this species, the male forcefully clasps the female’s genital region with his chelicerae and locks her fourth pair of legs with his pedipalps. In some cases, the cuticle of the female’s abdomen was damaged by this cheliceral clasping. In contrast to other camel-spiders, the female O. chacoensis never remained motionless during mating, but continuously shook her body, opening her chelicerae notably towards the male. Despite this coercive context, males performed copulatory courtship (tapping with pedipalps) and females showed an apparent cooperative behavior (they remained still during a short period of the sperm transfer phase). These results strengthen the idea that sexual coercion (in the form of forced copulation) and luring behavior (in the form of copulatory courtship) are not two mutually-exclusive male’s strategies during a single copulation.     

Monogyny and regulation of worker mating in the queenless antDinoponera quadriceps

The morphologically specialized queen caste has been lost in various ponerine ants, and mated workers (‘gamergates’) reproduce instead of queens. Unlike previous reports in the literature, we found only one gamergate in each colony ofDinoponera quadriceps. We documented monogyny by dissecting ovaries and spermathecae in 914 workers from 15 colonies, and by observing mating in the laboratory. In colonies without a gamergate, aggressive interactions among some of the unmated nestmates led to the behavioural differentiation of a top-ranking worker (‘alpha’), which laid almost all the eggs. Only the alpha went outside the nest at night, and mated if foreign males were present (N=11 tests), thus becoming a gamergate. The alpha was sexually attractive even when her ovaries were not yet active. After intromission, the male remained linked to the alpha while she severed the end of his abdomen. Pieces of the male genitalia remained attached to her genital tract, and she removed them after 30±18 min (X±sdN=9). We interpret this to be a mating plug, preventing other males from fathering her offspring. None of these newly inseminated gamergates continued to go outside the nest, and, when tested, they never re-mated (N=4). Thus, gamergates ofD. quadricepsprobably mate only once. In queenless ant species, comparative evidence indicates that worker mating is often regulated in monogynous species, while unrestricted mating of young individuals is typical of polygynous species (oviposition is regulated subsequently). Furthermore, the occurrence of either monogyny or polygyny influences the mating strategies of males, and mating plugs have been reported only in some monogynous species.     

Attraction of the sexes inFormica lugubris Zett (Hymenoptera: Formicidae)

Summary Sexuals ofFormica lugubris fly to mating places, where females attract males by using a sex pheromone. Females collected on the nest surface before departing on a mating flight are much less attractive than those collected on the mating place after the mating flight, suggesting that the mating flight triggers the release of the sex pheromone. Olfactory cues are essential for males to locate females while they patrol. Males probably use visual cues to locate females once they have alighted nearby them. Males are also attracted by aggregations of other males on the ground, probably because one or several females are likely to be close to male aggregations.     

The mating system of a bee fly (Diptera: Bombyliidae). I. Non-resource-based hilltop territoriality and a resource-based alternative

The mating system of an undescribed Australian bee fly (Comptosiasp. near lateralisNewman) was studied in Southeast Queensland. Males perched in clearings on a wooded hilltop and darted toward nearby flying insects. On sunny days males interacted with other insects about once per minute. A minority of these interactions was with conspecific males. They had the effect of determining ownership of the perching area. Most conspecific interactions occurred withtin 90 min of the first male's arrival each day, although territories were occupied for an average of 4.6 h per day. The same territories were used by different generations of flies for at least 4 years, while other apparently similar clearings on the hilltop remained unoccupied. Following removal of resident males, replacement males occupied the sites in 12.5 min on average. Females were not observed on the hilltop except when mating at territories. No interactive courtship behavior was detectable prior to midair coupling. Copulations lasted for 118 min on average. We interpret this as a landmark-based mating system and discuss it in relation to the concept of lek polygyny. Observations of Comptosiasp. near lateralismatings at a nonhilltop, resource-based encounter site suggest that the mating system of this species varies in response to the distribution of resources.     

Experimental evidence that brighter males sire more extra‐pair young in tree swallows

Across taxa, extra‐pair mating is widespread among socially monogamous species, but few studies have identified male ornamental traits associated with extra‐pair mating success, and even fewer studies have experimentally manipulated male traits to determine whether they are related directly to paternity. As a consequence, there is little experimental evidence to support the widespread hypothesis that females choose more ornamented males as extra‐pair mates. Here, we conducted an experimental study of the relationship between male plumage colour and fertilization success in tree swallows (Tachycineta bicolor), which have one of the highest levels of extra‐pair mating in birds. In this study, we experimentally dulled the bright blue plumage on the back of males (with nontoxic ink markers) early in the breeding season prior to most mating. Compared with control males, dulled males sired fewer extra‐pair young, and, as a result, fewer young overall. Among untreated males, brighter blue males also sired more extra‐pair young, and in paired comparisons, extra‐pair sires had brighter blue plumage than the within‐pair male they cuckolded. These results, together with previous work on tree swallows, suggest that extra‐pair mating behaviour is driven by benefits to both males and females.     

Limits to Nuptial Gift Production by Male Fireflies, Photinus ignitus

Males of diverse insect species provide females with nuptial gifts, and limits on males' ability to produce these gifts may influence courtship behavior and mating systems. In the firefly Photinus ignitus, males transfer a complex spermatophore to females during mating. We provided firefly males unlimited access to responsive females to examine whether spermatophore production limits male mating success. Male spermatophore mass decreased significantly across sequential matings, and the percentage of successful matings declined during the second half of each male's life span. Male body mass explained a significant proportion of variation in size of the first spermatophore produced by P. ignitus males, but this relationship disappeared with second spermatophores. This study indicates that males' ability to produce spermatophores declines over their lifetime and that limits on nuptial giftproduction can constrain male mating success in Photinus fireflies.