Mating Behavior Research Articles

Left-handed mating: lateralized mating behavior in a termite-associated rove beetle

Left-handed mating: lateralized mating behavior in a termite-associated rove beetle

Prevalence, geographic distribution, and transmission pathway of Camponotus yamaokai virus.

The relationship between hosts and viruses is influenced by various factors. One potential factor is sociality. In social organisms such as ants, the interaction between hosts and viruses might differ from those of solitary organisms due to their unique ecology. We previously isolated a double-stranded RNA toti-like virus, Camponotus yamaokai virus (CYV), from the arboreal ant Camponotus yamaokai. The ant exhibits a polygynous colony structure with multiple queens and within-nest mating behaviors. Such unique ecological traits may have driven the evolution of a distinctive relationship with the virus. However, the biological characteristics of CYV have not been sufficiently studied. In this study, we investigated the biological characteristics of CYV through rearing experiments and field surveys. No horizontal transmission between workers and broods was detected, and there were no significant differences in prevalence between castes. CYV was detected at all seven locations surveyed, with prevalence ranging from 60-95%. The high CYV prevalence across the host's distribution range indicates that the geographical distribution of CYV aligns with that of its host. These results suggest that CYV has spread throughout the host population, primarily through vertical transmission.

Modulation of strategic status signaling: oxytocin changes men's fluctuations of status products preferences in their female partners' menstrual cycle.

Women exhibit subtle fluctuations in mating-related behaviors throughout their menstrual cycle, and men are capable of detecting these ovulatory cues. This ability may impact male mating behavior, prompting adjustments in their preferences for consumer products based on these signals. Nonetheless, the potential influence of oxytocin on men's preferences for status products, particularly in the context of their female partners' menstrual cycles, is not yet known. This study aims to explore how oxytocin regulates men's responses to their female partners' ovulation in heterosexual romantic relationships by specifically examining changes in their preferences for status consumption. Through a pilot study (N = 110) and two main studies (N1 = 789, N2 = 120), we analyzed how oxytocin influences fluctuations in men's preferences for status products throughout their female partners' menstrual cycles. In Study 1, we examined the impact of the female menstrual cycle on men's preferences for status products. In Study 2, we employed intranasal oxytocin to investigate its modulatory effect on the menstrual cycle's influence. Findings revealed that men demonstrated a lower preference for status products during their partners' ovulation compared to non-ovulatory phases. Furthermore, intranasal oxytocin significantly reduced men's liking for status products during the ovulatory phase, but not during the menstrual phase, with a stronger effect observed among men with a heightened intuitive inclination. These results suggest that men in committed relationships strategically adapt their consumption of status products according to their female partners' menstrual cycles, with oxytocin playing a moderating role in this adaptation and individual differences influencing responses.

Evidence for the independent evolution of sex-related signals in manakins.

In birds, colouration, dance, and song evolved into great elaboration. Males most frequently produce these signals to attract females, and their evolution is undoubtedly affected by natural and sexual selection. Song, dance, and colouration are attributes commonly involved in mate attraction and are generally considered targets of sexual selection. In many species, multiple signalling is present, often involving different signal modalities, but we still know very little about how they interact during the evolution of different species. Here, we analysed manakin species, which present impressive displays, vibrant colouration, and simple songs, to determine if these multiple signals coevolved or if they evolved independently, which in the latter case would mean that different signal types will convey different messages. Moreover, we attempted to determine which environmental and morphological factors were related to the evolution of each signal. We found that song, dance and colour complexity evolved independently in manakins. The only exception was for dance complexity, which is negatively associated with plumage brilliance. We also found that dances were more complex in smaller species and habitats with less precipitation and appeared not to be related to the intensity of sexual selection. Differently, colour complexity evolution was only associated with sexual selection. Colour brightness was related to habitat cover and precipitation. Song complexity was unrelated to any of the predictors tested here. Our results indicate that colour, dance, and song evolved in an unrelated way, implying that they most likely have different signalling roles in the mating behaviour of these species, and they were revealed to be affected by different natural and sexual selection factors throughout their evolution.

Effect of Spiroplasma infection on the mating behavior of Glossina fuscipes fuscipes.

Tsetse flies are insects of significant public health and zoonotic importance as they are the main vectors of African trypanosomes. To date, an effective vaccine is unavailable and efforts to limit the spread of the disease primarily rely on controlling the tsetse populations. The discovery of Spiroplasma (class Mollicutes) in Glossina fuscipes fuscipes (Gff) (palpalis subgroup), offers promising insights into its potential use as a biological control agent to hinder trypanosomes infection in tsetse flies. Indeed, a negative correlation between Spiroplasma and trypanosome co-infection has been observed. Using a laboratory strain of Gff, we provide fundamental biological insights into the effects of Spiroplasma infection on the mating behavior of the fly. We found a sex-biased Spiroplasma infection, with males exhibiting a higher infection rate. Mass mating experiments revealed a higher mating propensity in Spiroplasma-infected flies. Additionally, the presence of Spiroplasma influenced premating isolation, leading to nonrandom mating patterns that favored the pairing of individuals with matching infection statuses. Moreover, we present evidence of Spiroplasma vertical paternal transmission. By analyzing female reproductive tissues at 2 and 24 h postmating, we confirmed that an infected male can transfer Spiroplasma to the female via the spermatophore, which can subsequently migrate to the spermathecae. This study provides foundational insights into the role of Spiroplasma in tsetse fly mating behavior and provides supporting evidence for vertical transmission from infected males.

Cellular evolution of the hypothalamic preoptic area of behaviorally divergent deer mice

Genetic variation is known to contribute to the variation of animal social behavior, but the molecular mechanisms that lead to behavioral differences are still not fully understood. Here, we investigate the cellular evolution of the hypothalamic preoptic area (POA), a brain region that plays a critical role in social behavior, across two sister species of deer mice (Peromyscus maniculatus and P. polionotus) with divergent social systems. These two species exhibit large differences in mating and parental care behavior across species and sex. Using single-nucleus RNA-sequencing, we build a cellular atlas of the POA for males and females of both Peromyscus species. We identify four cell types that are differentially abundant across species, two of which may account for species differences in parental care behavior based on known functions of these cell types. Our data further implicate two sex-biased cell types to be important for the evolution of sex-specific behavior. Finally, we show a remarkable reduction of sex-biased gene expression in P. polionotus, a monogamous species that also exhibits reduced sexual dimorphism in parental care behavior. Our POA atlas is a powerful resource to investigate how molecular neuronal traits may be evolving to give rise to innate differences in social behavior across animal species.

Cellular evolution of the hypothalamic preoptic area of behaviorally divergent deer mice.

Genetic variation is known to contribute to the variation of animal social behavior, but the molecular mechanisms that lead to behavioral differences are still not fully understood. Here, we investigate the cellular evolution of the hypothalamic preoptic area (POA), a brain region that plays a critical role in social behavior, across two sister species of deer mice (Peromyscus maniculatus and P. polionotus) with divergent social systems. These two species exhibit large differences in mating and parental care behavior across species and sex. Using single-nucleus RNA-sequencing, we build a cellular atlas of the POA for males and females of both Peromyscus species. We identify four cell types that are differentially abundant across species, two of which may account for species differences in parental care behavior based on known functions of these cell types. Our data further implicate two sex-biased cell types to be important for the evolution of sex-specific behavior. Finally, we show a remarkable reduction of sex-biased gene expression in P. polionotus, a monogamous species that also exhibits reduced sexual dimorphism in parental care behavior. Our POA atlas is a powerful resource to investigate how molecular neuronal traits may be evolving to give rise to innate differences in social behavior across animal species.

The influence of temperature on courtship and mate choice in a wolf spider: implications for mating success in variable environments.

The selection of animal signal form often changes significantly with the environment, yet signal form may be environment-dependent. Little is known about how variation in individual responses to changing environments affects the relationship between selection and the subsequent evolution of signal traits. To address this question, we assess the effects of variation in temperature on individual signaling and mating behavior responses across temperatures in the wolf spider Schizocosa floridana. By running repeated-measures trials, we find that temperature has predictable effects on signal form, but that the performance of individual courters is not consistent across temperatures. Traits associated with courtship rate generally increase at higher temperatures but inter-individual consistency in response to temperature change is low, despite consistent female preferences for increased courtship rate at all temperatures. Interestingly, the production of the likely most recently evolved signal component, the chirp, is consistent within signalers and predicts male performance across temperatures. Despite this, female preferences for chirp duration appear only at higher temperatures. Taken together, our results suggest that individual courter responses to changing temperatures have the potential to dampen or eliminate patterns of selection that are evident across temperatures. We discuss these results in light of current research on mating behavior and sexual selection.

Relationships between Sociosexuality and Dermatoglyphic Traits

In humans, prenatal development of brain dispositions to sex differences in mating behavior is difficult to study directly. Indirect prenatal markers, including dermatoglyphics, present a viable option. In this study we tested a hypothesis that some radio-ulnar contrasts in dermatoglyphic ridge counts could be related with human sociosexuality. Sociosexual Orientation Inventory (SOI) data from 180 young adults, along with fingerprints of their terminal phalanges (via hand scanning) were collected, and relationships between SOI and dermatoglyphics were analyzed. Typical sex differences in SOI were recorded with higher scores in males and lower in females. Among other results we found that on the index finger lower number of triradii and cores (i.e., mostly in loop type dermatoglyphic patterns) and radial-biased within-finger asymmetry in ridge counts typical for ulnar loops were connected with typical sex differences in SOI (higher in males and lower in females) while in subjects possessing an opposite dermatoglyphic arrangement – higher numbers of cores and triradii and ulnar-biased within-finger ridge count asymmetry typical in radial loops – sex differences in SOI scores disappeared. Recognized significant and systematic trends were mostly connected with variables derived from dermatoglyphic features on the 2nd and 4th fingers. Possible relationships with prenatal androgen causation are discussed.

Tyrosine hydroxylase- and serotonin-immunoreactive neurons in the thoracic ganglia of the Oriental fruit fly, Bactrocera dorsalis.

Tyrosine hydroxylase- and serotonin-immunoreactive neurons in the thoracic ganglia of the Oriental fruit fly, Bactrocera dorsalis.

Carbon Emission Minimization through Real-time Economic Dispatch

<p>Conventional electrical power systems often prioritize economic gain over environmental protection, which can lead to negative environmental consequences, such as emissions from thermal power plants. In recent years, there has been significant research and investment aimed at addressing the challenges posed by both environmental restrictions and economic dispatch. This study introduces the Black Widow Optimization (BWO) technique to optimize the integration of Renewable Energy Sources (RES) in the context of effective economic dispatch. The BWO algorithm is inspired by the unique mating behaviors of black widow spiders, where cannibalism plays a crucial role in the process. To achieve faster convergence, the BWO removes species with poor fitness from the population. Compared to other optimization algorithms, BWO offers several advantages, including early convergence and the ability to achieve higher fitness values. To assess the performance of the proposed approach, we applied it to various test cases, including a 10-unit generator system, the IEEE 30-bus system, and the real-time 62-bus Indian Utility System (IUS), which incorporates RES output. The results show that, in comparison to other contemporary algorithms, the BWO method significantly reduces fuel costs, as demonstrated by both the Probability Distribution Function (PDF) and the Cumulative Distribution Function (CDF).</p>

Evolution and co-evolution of the suck behaviour, a postcopulatory female resistance trait that manipulates received ejaculate

BackgroundSexual conflicts over the post-mating fate of received ejaculate can favour traits in one sex that are costly to the other. Reciprocally mating hermaphrodites face unique challenges as they mate simultaneously in both the male and female role, potentially leading to receipt of unwanted ejaculate. Reciprocal mating can then give rise to postcopulatory female resistance traits that allow manipulation of received ejaculate. A putative example is the suck behaviour, observed in the flatworm genus Macrostomum. It involves the sperm recipient placing its pharynx over its own female genital opening and appearing to suck, likely removing received ejaculate after mating. The genus also contains hypodermically inseminating species that presumably exhibit unilateral mating and have not been observed to suck.ResultsHere, we examine the evolution of the suck behaviour in the Macrostomum genus, aiming to document the mating behaviour in 64 species. First, we provide videographic evidence that ejaculate is indeed removed during the suck behaviour in a reciprocally mating species, Macrostomum hamatum. Next, we show positive evolutionary correlations between the presence, duration and frequency of reciprocal mating behaviour and the suck behaviour, providing clear evidence that the suck behaviour co-evolves with reciprocal mating behaviour. Finally, we show an association between reproductive behaviour and reproductive morphology, suggesting that the reproductive morphology can be used to infer a species’ mating behaviour.ConclusionsTogether, our study demonstrates sexually antagonistic coevolution leading to the evolution of a postcopulatory behavioural trait that functions as a female counter-adaptation allowing individuals to gain control over received ejaculate in a hermaphroditic sexual system.

Habituation to intraspecific mating inhibition signals in the tea leafhopper, Empoasca onukii.

Pest control mediated by substrate-borne vibrational signals has been successfully used to control the grapevine leafhopper. Maintaining the signal intensity above the effective threshold and avoiding habituation to the stimulus are crucial for this control strategy to be effective. The tea leafhopper, Empoasca onukii, is a major pest of tea plants that relies on substrate-borne vibrational signals for mating communication. Male rivals can emit specific competitive signals (MDSs) to inhibit the calling activity of a courting male. The effective intensity threshold of E. onukii MDSs was 20 μm/s; when this threshold was exceeded, MDSs completely inhibited the calling activity of males. Repeated playback of MDSs in the closed-loop or open-loop mode triggered the habituation of E. onukii males to the stimulus. Insertion of a male calling signal (MCaS) during the stimulus resulted in male dishabituation, but insertion of the female signal did not. Compared with the closed-loop mode, the open-loop mode is more suitable for the development of mating inhibition technology for E. onukii. Combined with the MCaS's dishabituation function, a mating inhibition signal synthesized with repeated MDSs has the potential for long-term inhibition of E. onukii mating behavior. © 2025 Society of Chemical Industry.

Fighting-related injuries do not affect mate choice in the giant mesquite bug, Pachylis neocalifornicus

Abstract Females often choose high-quality mates as they may confer benefits to the female. One way male quality may decline is due to the injuries that they can acquire during male-male combat. Females might assess males based on injury since injuries place energic demands on the body that could reduce their reproductive output. Thus, females might make mating decisions based on whether males have acquired these fighting-related injuries. Here, we tested this injury-mediated female mate choice hypothesis using the giant mesquite bug, Pachylis neocalifornicus (Hemiptera: Coreidae). This hypothesis predicts that females will choose uninjured males over injured males. We simulated non-lethal injuries that males could acquire during male-male contests and assayed mate choice. We compared mate choice of the injury group to a control group and found that fighting-related injuries did not affect mate choice. However, females were more likely to mate with males that had large sexually selected weapons while males were more likely to make mating attempts with large-bodied females. Additionally, the smaller a male’s weaponry the more quickly they initiated their mating attempts. Our results do not support the injury-mediated mate choice hypothesis. Instead, they reveal that other factors besides fighting-related injuries appear to have a larger role in determining mating behavior patterns in this species.

The Influence of Hypoxic Conditions on Mating Behavior in a Bimodal Breather, the Great Pond Snail (Lymnaea stagnalis).

AbstractReduced oxygen availability can become an environmental stressor that imposes constraints on the energy and/or time budget of aquatic animals. This also seems to be the case for bimodal breathers, since it was previously reported that the amount of oxygen in the water interacts with feeding and egg-laying activities. The great pond snail (Lymnaea stagnalis) is a typical bimodal breather and a simultaneous hermaphrodite for which both male and female mating behaviors have been studied in detail. The aim of this study was to test whether hypoxic conditions affect mating behavior in this bimodal breather and to investigate whether mating motivation and the choice of sexual role is influenced by this environmental condition. Our results show that when oxygen cannot be acquired via cutaneous respiration or aerial respiration, mating and locomotion are inhibited. When oxygen is available only via air, the occurrence of unilateral insemination, reciprocal insemination, and biting behavior is reduced and courtship duration is decreased compared to when oxygen is also available in the water. Our results indicate that depending on the oxygen availability in the environment, water, and air, this bimodal breather has to weigh its motivation to mate against its need for cutaneous and/or aerial respiration. These findings contribute to our understanding of how animals optimize their behavioral investment decisions under changing environmental circumstances.

Exposure to sex pheromone from the pupal stage through eclosion has contrasting effects on subsequent mating behaviors of codling moth and oriental fruit moth adults.

Mating disruption is achieved by releasing synthetic pheromones into crop systems to disrupt natural mating behavior of targeted pests. Dispensers of synthetic pheromones are deployed in various crops with the intent of limiting males from finding females thereby reducing or delaying mating to lower pest populations over time. Codling moth (CM) (Cydia pomonella L.) and oriental fruit moth (OFM) (Grapholita molesta) (Busck) are worldwide pests of pome and stone fruits. We investigated the hypothesis that pupal exposure to species-specific sex pheromones affects subsequent mate-finding ability, mating behavior, and reproductive output of adult CM and OFM. Laboratory experiments revealed that pheromone exposure during the pupal stage significantly impacts CM reproductive output and mate-finding, whereas these effects were not observed with OFM. Our findings suggest that targeted deployment of pheromones to cause pupal exposure may enhance control of certain species such as CM.

Characteristics and seasonal variation of fall armyworm migratory behavior in their year-round breeding areas in South China.

The occurrence of migratory takeoff behavior is the essential first step for long-distance migration of insects. However, its characteristics, frequency of occurrence, and the identity of environmental and physiological factors influencing this process remain largely unknown. We investigate the global pest fall armyworm (FAW, Spodoptera frugiperda) as an exemplar species to investigate the behavioral traits associated with migratory takeoff of nocturnally migrating moths in year-round breeding areas. Our studies of FAW were carried out in Yunnan (2020-2022) and Hainan (2023) provinces of South China. Most migratory FAW moths were observed to takeoff at the age of Day (D)1-3, with the highest migratory proportion on D2, whereas mating behavior mostly happened during the first half night on D1. Typically, the migratory individuals took off within 40 min after sunset when the illumination fell below 2.7 lx, reaching its peak within 15 min. The optimal conditions for their takeoff are warm and dry weather with gentle winds. Yunnan and Hainan field populations showed a similar seasonal pattern in their migratory proportion, with the highest proportion in spring, and then decreasing as the seasons progress. Additionally, FAW moths emerging from caterpillars fed on maize plants at V14-R1 stages showed a higher migratory proportion than those from larvae fed on maize plants at other growth stages. Compared with nonmigratory individuals, migratory ones had slightly longer forewings (marginally significant) and flew faster, with higher wingbeat frequency, but other morphological characteristics and flight parameters were similar. The study of FAW moths in Yunnan and Hainan from 2020 to 2023 found that migratory moths take off under specific conditions and show a seasonal pattern, with those from certain maize stages having higher migratory proportion, longer forewings and faster flight. These findings advance our understanding of the migratory takeoff behavior of FAW and, thus, provide a basis for the accurate prediction and management of the migratory dynamics. © 2025 Society of Chemical Industry.

Temporal and Spatial Patterns of Mating in Rhodnius prolixus

The kissing bug Rhodnius prolixus is a nocturnal species; however, its temporal mating patterns remain unexplored. Copulation lasts about fifty minutes, during which time the couple remains almost motionless. We hypothesized that R. prolixus copulates within shelters to reduce its vulnerability. To test this, we examined the spatial and temporal patterns of its copulation, as well as the potential endogenous regulation of its circadian rhythm, under three conditions: a light:dark cycle (L/D), constant light (L/L), and constant darkness (D/D). Over ten days, the number and the timing of copulation of pairs in arenas containing a shelter were video-recorded. Under the L/D cycle, the pairs mated mainly during daylight hours. This rhythm persisted under the D/D cycle, with a peak extending from the first half of the subjective day to the first half of the subjective night. No rhythm was observed under the L/L cycle. A greater proportion of mating occurred within the shelters during the L/D and L/L cycles, whereas its spatial distribution was random under the D/D cycle. Our results reveal an endogenously controlled circadian rhythm of mating behavior, with mating activity mainly occurring during daylight hours. Additionally, we showed that the pairs copulated inside the shelters. These results provide new insights into the reproductive behavior of R. prolixus.

Exploring marking methods for the predatory hoverfly Sphaerophoria rueppellii (Diptera: Syrphidae).

Hoverflies are essential to ecosystems, with adults serving as important pollinators and larvae preying on plant-feeding insects or recycling nutrients. Species like Sphaerophoria rueppellii are used in biocontrol programs to target aphid pests. To enhance these programs, markers can be used in a mark-release-recapture (MRR) method to track hoverfly feeding and oviposition sites. Effective markers must be persistent and not harm the hoverflies' vital functions. This study evaluated three marking methods for S. rueppellii: rubidium (RbCl), fluorescein, and fluorescent dust. Laboratory experiments assessed the effects of these markers on female hoverfly fecundity, mating behavior and marking persistence. Results showed no significant differences in egg-laying or survival time between marked and unmarked females. Rubidium and fluorescein did not affect mating behavior, but dust-treated females mated significantly less than untreated females. In terms of marking persistence, rubidium and fluorescent dusts remained detectable throughout the hoverflies' adult lifespan, while fluorescein markings faded within 24 h. Fluorescent dusts were easy-to-use, durable, and cost-effective, but careful application and further study are needed to avoid potential effects on insect activity and mating ability. Fluorescein showed no adverse effects on insect biology, was economical and quick to apply, but had short persistence, making it unsuitable for long-term field studies. Rubidium was harmless to insects and detectable for long periods, but its detection required financial investment, time, and specialized equipment. This research provides valuable insights into the potential of hoverflies as biocontrol agents and offers new tools for their effective management in agricultural settings.

Doublesex regulates male sexual development in the cricket Gryllus bimaculatus.

Insects have evolved a diversity of regulatory mechanisms to determine their sex. Understanding the molecular regulation mechanisms of insect sex determination is of great significance in revealing the general law of insect sex determination and providing potential routes for the genetic manipulation of pest species. Although the sex determination cascade and doublesex (dsx) gene functions have been well described in some holometabolous insects, little is known about this cascade in hemimetabolous insects. In this study, we identified the dsx homolog in Gryllus bimaculatus, which belongs to the Orthoptera order and is an important model for developmental and evolutionary biology. We found that Gbdsx has two alternative splicing isoforms (male-specific GbdsxM and non-sex-specific GbdsxC). Using RNAi-mediated knock-down of GbdsxM in 6th-instar nymphs resulted in adult male forewings showing feminized vein development and abnormal external genitalia. CRISPR/Cas9 knockout of Gbdsx in embryos resulted in adult males becoming pseudofemales, with feminized forewings and abnormal external and internal genitalia. Additionally, the pseudofemales created by Gbdsx knockout demonstrated normal courtship trends and aggressive behavior but no actual mating behavior. However, the knockout and knock-down of Gbdsx in female crickets does not affect their sexual traits or fertility. Our results suggest that GbdsxM plays a critical role in the development of male cricket sexual traits, courtship and mating behavior, which furthers our understanding of sex determination in hemimetabolous insects.