Differences In Mating Behavior Research Articles

A Psychometric Evaluation of the Intrasexual Competition Scale.

The Intrasexual Competition Scale (ICS) measures the extent to which individuals view their interaction with same-sex others in competitive terms. Although it is frequently used in studies investigating differences in mating behavior, the factor structure of the ICS has never been confirmed. Researchers have yet to use multiple-group confirmatory factor analysis to test whether the properties of the scale are equivalent between the sexes. In Study 1, we report on an investigation in which participants' responses to the ICS were submitted to exploratory factor analysis (EFA). In Study 2A, we compared the fit of one and two-factor models from the EFA as well as two additional models, using confirmatory factor analysis with an independent sample. The best fit was obtained by a two-factor solution, which reflected: (1) respondents' feelings of frustration when intrasexual competitors are better off (Inferiority Frustration), and (2) respondents' enjoyment of being better than intrasexual competitors (Superiority Enjoyment). This model achieved a high degree of measurement invariance. In Study 2B, we found the ICS had good concurrent validity via associations with sociosexuality, mating effort, and sexual behavior. Together, these analyses suggest that the ICS is a valid measure of intrasexually competitive attitudes.

Ultraviolet polarized light and individual condition drive habitat selection in tropical damselflies and dragonflies

Artificial objects can polarize ultraviolet light sources to a higher degree than natural objects like water bodies. This can induce a strong attraction response by insects that use such cues as proxies of habitat suitable for reproduction. Visible range polarized light (VRPL) can create evolutionary traps for aquatic insects, but it remains unclear whether insects can use ultraviolet polarized light (UVPL) as a habitat selection cue or if UVPL pollution can create evolutionary traps for aquatic insects like VRPL can. Odonate (dragonflies and damselflies) insects require an aquatic habitat to perform their mating and egg-laying behaviours yet they also perform such behaviours on artificial surfaces (i.e. metal pieces). We measured the preference for UVPL versus VRPL via exposing three species of odonates (Enallagma praevarum, Ischnura denticollis and Sympetrum illotum) to experimental test surfaces differing in these visual cues and assessing behavioural preference via differences in mating behaviour, body condition (i.e. lipid and protein content and body size) and visual acuity (based on eye width size). Ischnura denticollis performed more diverse mating behaviours in association with the VRPL treatment, while S. illotum preferentially exhibited these behaviours in association with the UVPL. Ischnura denticollis individuals associated with the preferred habitat had lower lipid reserves, smaller body size and larger eyes, while habitat preference was unrelated to individual condition and morphology in E. praevarum and S. illotum. These results suggest intra- and interspecific variation in trap preferences, which are related to individual condition. They also show that UVPL is a cue that odonates use in habitat selection that has the potential to create evolutionary traps, suggesting conservation problems for aquatic insects that rely upon it to locate water bodies.

Asymmetric mating behavior of isogamous budding yeast.

Anisogamy, the size difference between small male and large female gametes, is known to enable selection for sexual dimorphism and behavioral differences between sexes. Nevertheless, even isogamous species exhibit molecular asymmetries between mating types, which are known to ensure their self-incompatibility. Here, we show that different properties of the pheromones secreted by the MATa and MATα mating types of budding yeast lead to asymmetry in their behavioral responses during mating in mixed haploid populations, which resemble behavioral asymmetries between gametes in anisogamous organisms. MATa behaves as a random searcher that is stimulated in proportion to the fraction of MATα partner cells within the population, whereas MATα behaves as a short-range directional distance sensor. Mathematical modeling suggests that the observed asymmetric responses can enhance efficiency of mating and might thus provide a selective advantage. Our results demonstrate that the emergence of asymmetric mating behavior did not require anisogamy-based sexual selection.

Do differences in mating behaviour lead to differences in connectivity patterns of reef fishes? Insights from two sympatric surgeonfish species in the Indian Ocean

Disentangling the contribution of biotic and abiotic factors in the structuring of the genetic diversity of reef species is critical to illuminate the diversification of evolutionary lineages in marine environment. Howevr, previous studies have mainly focused on determining the influence of pelagic larval duration on the connectivity and demographic history of reef fishes, whereas few studies have examined the effects of other biotic factors, such as mating behaviour and habitat preference. Here, we use mitochondrial DNA (ATPase 6/8) and ten microsatellite loci to compare the population genetic structure and demographic history of the spawning aggregating Acanthurus triostegus with the monogamous spawning Acanthurus leucosternon. Pairwise comparisons and discriminant analysis of principal components showed that the genetic structuring patterns of the two species are not consistent with the influence of mating behaviour, suggesting the possible role of other biotic and abiotic factors. However, demographic history estimates revealed that these species may have responded differently to sea level fluctuations during the glacial maxima.

Comparisons in geese of the courtship, mating behaviors and fertility of the Carlos and Sichuan breeds and the breed crosses

The Chinese goose originated from the swan goose (Anser cygnoides) and the European goose originated from the greylag goose (Anser anser). The Chinese and European geese have the potential to crossbreed. Whether interspecific differences in mating behaviors affect successful hybridization is unknown. In this study, 10-month-old Carlos geese (n = 120; Anser anser) and Sichuan geese (Anser cygnoides) were selected, and 12 multi-male parent families (3♂+12♀) were established. The courtship and mating behaviors of pure and cross-bred combinations of the Carlos and Sichuan geese were recorded using video cameras. Initiative courtship by males was the main type of courtship. Fixed mating, mating interference, and uncooperative mating were common in the flocks. The frequencies of some courtship and mating behaviors were less in the cross-bred groups (Carlos ganders × Sichuan geese, Sichuan ganders × Carlos geese) compared with the Sichuan pure-bred groups (P < 0.05). The Carlos male geese had some unique mating behaviors (i.e., one-to-one mating, formation of distinct hierarchies, and competition interference). The fertility rate had a significant correlation with the frequency of successful mating (rp = 0.992, P < 0.05), rather than with the courtship behavior. These results indicate there were lesser frequencies of courtship and successful matings in the cross-breeding than purebreeding groups. Furthermore, the fertility rate depended largely on the successful mating behavior and was independent of the courtship behavior.

QTL Determining Diel Flight Activity in Male Culex pipiens Mosquitoes.

Members of the Culex pipiens complex differ in physiological traits that facilitate their survival in diverse environments. Assortative mating within the complex occurs in some regions where autogenous (the ability to lay a batch of eggs without a blood meal) and anautogenous populations are sympatric, and differences in mating behaviors may be involved. For example, anautogenous populations mate in flight/swarms, while autogenous populations often mate at rest. Here, we characterized flight activity of males and found that anautogenous strain males were crepuscular, while autogenous strain males were crepuscular and nocturnal, with earlier activity onset times. We conducted quantitative trait locus (QTL) mapping to explore the genetic basis of circadian chronotype (crepuscular vs. crepuscular and nocturnal) and time of activity onset. One major-effect QTL was identified for chronotype, while 3 QTLs were identified for activity onset. The highest logarithm of the odds (LOD) score for the chronotype QTL coincides with a chromosome 3 marker that contains a 15-nucleotide indel within the coding region of the canonical clock gene, cryptochrome 2. Sequencing of this locus in 7 different strains showed that the C-terminus of CRY2 in the autogenous forms contain deletions not found in the anautogenous forms. Consequently, we monitored activity in constant darkness and found males from the anautogenous strain exhibited free running periods of ~24 h while those from the autogenous strain were ~22 h. This study provides novel insights into the genetic basis of flight behaviors that likely reflect adaptation to their distinct ecological niches.

The Genetics of Mating Song Evolution Underlying Rapid Speciation: Linking Quantitative Variation to Candidate Genes for Behavioral Isolation.

Differences in mating behaviors evolve early during speciation, eventually contributing to reproductive barriers between species. Knowledge of the genetic and genomic basis of these behaviors is therefore integral to a causal understanding of speciation. Acoustic behaviors are often part of the mating ritual in animal species. The temporal rhythms of mating songs are notably species-specific in many vertebrates and arthropods and often underlie assortative mating. Despite discoveries of mutations that disrupt the temporal rhythm of these songs, we know surprisingly little about genes affecting naturally occurring variation in the temporal pattern of singing behavior. In the rapidly speciating Hawaiian cricket genus Laupala, the striking species variation in song rhythms constitutes a behavioral barrier to reproduction between species. Here, we mapped the largest-effect locus underlying interspecific variation in song rhythm between two Laupala species to a narrow genomic region, wherein we find no known candidate genes affecting song temporal rhythm in Drosophila Whole-genome sequencing, gene prediction, and functional annotation of this region reveal an exciting and promising candidate gene, the putative cyclic nucleotide-gated ion channel-like gene, for natural variation in mating behavior. Identification and molecular characterization of the candidate gene reveals a nonsynonymous mutation in a conserved binding domain, suggesting that ion channels are important targets of selection on rhythmic signaling during establishment of behavioral isolation and rapid speciation.

Intrinsic pre-zygotic reproductive isolation of distantly related pea aphid host races.

Human activities may weaken or destroy reproductive isolation between young taxa, leading to their fusion with consequences for population and community ecology. Pea aphid host races are adapted to different legume taxa, providing a degree of pre-mating isolation mediated by habitat choice. Yet, all races can feed and reproduce on the broad bean (Vicia faba), a major crop which represents a 'universal host plant', which can promote hybridization between races. Here, we ask if pea aphid host races have reproductive barriers which prevent or reduce gene flow when they co-occur on the universal host plant. We observed mating behaviour, female survival, number of eggs and egg fertilization rates for three types of crosses: among individuals of the same host race, between closely related host races and between distantly related host races. We did not find significant differences in mating behaviour and female survival among the three types of crosses. However, we observed a drastic reduction in the number of eggs laid, and in the number of fertilized eggs, in distant crosses. We conclude that widespread broad bean cultivation in agriculture may predispose closely related-but not distantly related-host races to hybridize, disrupting reproductive isolation between incipient species.

Male Hatano low-avoidance rats show more active sexual behavior with lower plasma testosterone than high-avoidance rats.

Two inbred strains of Sprague-Dawley rats, known as the Hatano high- and low-avoidance animals (HAA and LAA respectively), have been selectively bred for high versus low rates of avoidance responses in a shuttle-box avoidance task. To investigate differences in the sexual behavior of Hatano rats, male HAA, LAA and SD rats were tested from 12 to 15 weeks of age. LAA rats exhibited more rapid and frequent sexual behavior than HAA or SD rats, and such differences increased with repeated sexual experience. Plasma testosterone levels tended to be lower in LAA rats than in HAA or SD rats, suggesting that active sexual behavior in LAA rats is not related to these levels. Strain differences in mating behavior between HAA and LAA rats may be caused by emotional responses to novelty.

Differences in mating behavior between two allopatric populations of a Neotropical scorpion

Courtship and mating behavior generally evolve rapidly in diverging populations and species. The adaptation to different environments may cause behavioral divergence in characteristics involved in mate choice. Our objective in this study was to compare the sexual behavior of two distant populations of the scorpion Bothriurus bonariensis. This species has a broad distribution in South America, inhabiting Central Argentina, Uruguay and south-eastern Brazil. It is known that in this species there is a divergence in morphological patterns (body size, coloration, allometry and fluctuating asymmetry indexes) among distant populations. Considering the differences in environmental conditions between localities, we compare the sexual behavior in intra-population and inter-population matings from Central Argentina and southern Uruguay populations. We found significant differences in mating patterns, including differences in the frequency and duration of important stimulatory courtship behaviors. In addition, most inter-population matings were unsuccessful. In this framework, the differences in reproductive behavior could indicate reproductive isolation between these populations, which coincides with their already known morphological differences. This is the first study comparing the sexual behavior of allopatric populations of scorpions; it provides new data about the degree of intraspecific geographical divergence in the sexual behavior of B. bonariensis.

The potential for disruptive selection on growth rates across genetically influenced alternative reproductive tactics

A trade-off between survival to sexual maturity and mating success is common across alternative reproductive tactics (ARTs), and can lead to tactical disruptive selection on shared traits (i.e. positive selection gradient in one tactic, and negative selection gradient in another). We were interested in examining the theoretical possibility of tactical disruptive selection on intrinsic growth rate. The male ARTs in Xiphophorus multilineatus express two distinct life histories: “courters” optimize mating success by maturing later at larger size and coaxing females to mate, while “sneakers” optimize survival to sexual maturity by maturing earlier at a smaller size, using both coaxing and coercive mating behaviors. In addition to differences in mating behaviors, body length, body depth, and the pigment pattern vertical bars, courter males grow faster than sneaker males. We present a new hypothesis for differences in growth rates between genetically influenced ARTs. The “growth-maturity optimization” hypothesis suggests that ARTs with differences in the probability of surviving to sexual maturity may have different optimal growth rates, leading to tactical disruptive selection. We also present a simple model to suggest that when considering both a cost and benefit to faster growth, tactical disruptive selection on growth rates is theoretically possible. In our model, the value that determines when tactical disruptive selection on growth rate will occur is the increase in probability of survival to sexual maturity gained through faster growth multiplied by the cost of faster growth (reduced longevity). Finally, we present empirical evidence to support the prediction that faster growth has a cost in X. multilineatus: in a controlled laboratory setting, courter males that did not survive 1.2 years past sexual maturity grew faster as juveniles (14–70 days) than those that survived.

'Does my Diet Affect my Perfume?' Identification and Quantification of Cuticular Compounds in Five Drosophila melanogaster Strains Maintained over 300 Generations on Different Diets.

Cuticular hydrocarbons (CHCs) in Drosophila melanogaster represent the basis of chemical communication being involved in many important biological functions. The aim of this study was to characterize chemical composition and variation of cuticular profiles in five D. melanogaster strains. These strains were reared for approximately 300 generations on five diets: standard cornmeal medium and substrates prepared with apple, banana, tomato, and carrot. Differences in quantity and/or quality in CHCs were assumed as a result of activation of different metabolic pathways involved in food digestion and adaptations to the particular diet type. In total, independently of sex and strain, 66 chemical compounds were identified. In females of all strains, 60 compounds were identified, while, in males, 47 compounds were extracted. Certain new chemical compounds for D. melanogaster were found. MANOVA confirmed that CHC amounts significantly depend on sex and substrates, as well as on their interactions. Discriminant analysis revealed that flies belonging to 'apple' and 'carrot' strains exhibited the most noticeable differences in CHC repertoires. A non-hydrocarbon pheromone, cis-vaccenyl acetate (cVA) also contributed to the variation in the pheromone bouquet among the strains. Variability detected in CHCs and cVA may be used in the explanation of differences in mating behaviour previously determined in analyzed fly strains.

Functional morphology of the copulatory organs of a reed beetle and a shining leaf beetle (Coleoptera: Chrysomelidae: Donaciinae, Criocerinae) using X-ray micro-computed tomography.

For more than 100 years it has been known that the sclerotised median lobe of beetles harbours a membranous structure (the "internal sac" or "endophallus") which is everted during copula inside the female genital tract. In order to explore the functional role of this structure and those associated with it, we cryofixed copulating pairs of Donacia semicuprea and Lilioceris lilii and studied the relative position of the elements of the copulatory apparatus of males and females by micro-computer-tomography.We found that the everted endophallus fills the lumen of the bursa copulatrix completely. Our data suggest that in Lilioceris lilii the tip of the sclerotised distal part of the ejaculatory duct, the flagellum, is positioned exactly over the opening of the spermathecal duct inside the bursa copulatrix. The mouth of the bursa copulatrix in Donacia semicuprea is armed with a strong muscle ring, and the whole wall of the bursa is covered externally with a layer of muscle fibres. These morphological differences correspond with differences in mating behaviour: In reed beetles (Donaciinae), females seemingly can control mating to a higher degree than in lily beetles (Lilioceris spp.).

Effects of Female fruit-marking Pheromones on Oviposition, Mating, and Male Behavior in the Neotropical Species Rhagoletis conversa Bréthes and Rhagoletis brncici Frías (Diptera: Tephritidae).

Sex pheromones produced by females of Rhagoletis conversa Bréthes and Rhagoletis brncici Frías are deposited on the surface of fruits after the eggs are laid. These pheromones repel other females, preventing repeated oviposition on the same fruit. They also attract males, thus assisting mating. Observations were made on wild populations, and cross-species behavioral tests were performed on males. The pheromone released by females was significantly more attractive for males of the same species. The two species showed remarkable differences in mating behavior, in the duration of oviposition, and in the number of circuits made around the fruit after eggs were laid. A morphological analysis of flies collected from their respective host plants indicated great host fidelity and the reproductive isolation of the two species. Possibly, the specific male-arresting effect of this pheromone was important for the sympatric speciation and evolution of these sibling species.

Spanish

This research aims to provide a new perspective on understanding and differentiation of play behavior in the phase of positional attack in the male and female beach handball. 28 high-level games with Hoisan software were analyzed. The observational design used is nomothetic, monitoring and multidimensional. The taxonomic system has been validated methodologically. Data were subjected to analysis of polar coordinates in its genuine version. To carry out these analyzes on seven focal behaviors were chosen mainly for players who complete the attack and how to create it. The results showed differences in mating behavior in the male and female category. Emphasizes that the positional attack in the female category is geared towards areas left defensive end to an open system depends more on the player who takes the role of caretaker double (specialist) in the men's category, where responsibilities are more spread and attack directed toward the right sideline before a closed defense system. The shoot in pirouette has been shown as the main offensive action in both categories. A b s t r a c t

Bateman's principle is reversed in a cooperatively breeding bird

Bateman's principle is not only used to explain sex differences in mating behaviour, but also to determine which sex has the greater opportunity for sexual selection. It predicts that the relationship between the number of mates and the number of offspring produced should be stronger for males than for females. Yet, it is unclear whether Bateman's principle holds in cooperatively breeding systems where the strength of selection on traits used in intrasexual competition is high in both sexes. We tested Bateman's principle in the cooperatively breeding superb starling (Lamprotornis superbus), finding that only females showed a significant, positive Bateman gradient. We also found that the opportunity for selection was on average higher in females, but that its strength and direction oscillated through time. These data are consistent with the hypothesis that sexual selection underlies the female trait elaboration observed in superb starlings and other cooperative breeders. Even though the Bateman gradient was steeper for females than for males, the year-to-year oscillation in the strength and direction of the opportunity for selection likely explains why cooperative breeders do not exhibit sexual role reversal. Thus, Bateman's principle may not hold in cooperative breeders where both sexes appear to be under mutually strong sexual selection.

Behavioural barriers to reproduction may evolve faster than sexual morphology among populations of a dung fly (Sepsidae)

Reproductive traits often evolve rapidly, and some suggest that behavioural traits, in particular, can diverge faster than morphology, resulting in sexual isolation between populations/species. An earlier study of a Neotropical dung fly, Archisepsis diversiformis (Diptera: Sepsidae), reported anecdotally that two central American populations that were approximately 500 km apart (Costa Rica and Panama) differed in male courtship behaviour despite being morphologically similar. Here, I present results of an in-depth study designed (1) to test whether these two populations show qualitative and/or quantitative differences in mating behaviour and morphology, (2) to test whether individuals from either population show some degree of reproductive isolation and (3) to characterize population variation in a particularly fast evolving mitochondrial gene fragment, cytochrome oxidase c subunit I (COI), to estimate genetic differences between the two populations. Despite similarities in overall courtship, I identified behaviours that were clearly population specific, and report that both populations showed strong premating isolation in one-on-one crosses. However, after extended exposure in mass-container group crosses, individuals did produce adult F1 offspring, suggesting that isolation is incomplete. Surprisingly, morphometric analyses indicated that these two populations differed significantly in sexually monomorphic adult wing shape but differed only moderately in sexually dimorphic male forefemur shape, and not at all in male genital clasper shape. Finally, both populations were genetically similar, forming a single, monophyletic cluster with low uncorrected pairwise distances (COI threshold <1 %), suggesting that marked behavioural differences between both populations have evolved quickly but without complete isolation.

Multi-well imaging of development and behavior in Caenorhabditis elegans

BackgroundThe nematode Caenorhabditis elegans is widely used as a model for understanding the neuronal and genetic bases of behavior. Recent studies have required longitudinal assessment of individual animal's behavior over extended periods. New methodHere we present a technique for automated monitoring of multiple worms for several days. Our method uses an array of plano-concave glass wells containing standard agar media. The concave well geometry allows worms to be imaged even at the edge of the agar surface and prevents them from burrowing under the agar. We transfer one worm or embryo into each well, and perform imaging of the array of wells using a single camera. Machine vision software is used to quantify size, activity, and/or fluorescence of each worm over time. ResultsWe demonstrate the utility of our method in two applications: (1) quantifying behavioral quiescence and developmental rate in wild-type and mutant animals, and (2) characterizing differences in mating behavior between two C. elegans strains. Comparison with existing method(s)Current techniques for tracking behavior in identified worms are generally restricted to imaging either single animals or have not been shown to work with arbitrary developmental stages; many are also technically complex. Our system works with up to 24 animals of any stages and is technically simple. ConclusionsOur multi-well imaging method is a powerful tool for quantification of long-term behavioral phenotypes in C. elegans.

Pigment-Dispersing Factor Modulates Pheromone Production in Clock Cells that Influence Mating in Drosophila

Social cues contribute to the circadian entrainment of physiological and behavioral rhythms. These cues supplement the influence of daily and seasonal cycles in light and temperature. In Drosophila, the social environment modulates circadian mechanisms that regulate sex pheromone production and mating behavior. Here we demonstrate that a neuroendocrine pathway, defined by the neuropeptide Pigment-Dispersing Factor (PDF), couples the CNS to the physiological output of peripheral clock cells that produce pheromones, the oenocytes. PDF signaling from the CNS modulates the phase of the oenocyte clock. Despite its requirement for sustaining free-running locomoter activity rhythms, PDF is not necessary to sustain molecular rhythms in the oenocytes. Interestingly, disruption of the PDF signaling pathway reduces male sex pheromones and results in sex-specific differences in mating behavior. Our findings highlight the role of neuropeptide signaling and the circadian system in synchronizing the physiological and behavioral processes that govern social interactions.

Using Radio Telemetry to Assess Movement Patterns in a Giant Rhinoceros Beetle: Are There Differences Among Majors, Minors, and Females?

The Japanese horned beetle Trypoxylus dichotomus is a peculiar example of a maledimorphic species that does not exhibit any alternative reproductive tactics. Typically, differences in male morphology correspond to marked differences in mating behaviors (Dominey 1984; Gross 1996). Large males tend to adopt aggressive, territorial tactics to attract and secure females, while small or otherwise inferior males try to mate via sneak or satellite tactics, or by dispersing away from dominant males (reviewed in Oliveira et al. 2008). Alternative reproductive tactics are expected to favor distinct male morphologies, because exaggerated weapons that confer fighting advantages to dominant males should impair dispersal and sneaking capabilities (Moczek and Emlen 2000; Madewell and Moczek 2006). Although alternative reproductive tactics have been described in a number of dimorphic beetle species (Eberhard 1982; Rasmussen 1994; Emlen 1997; Moczek and Emlen 2000), T. dichotomus major and minor males apparently do not have distinct mating behaviors. Large major males have a long, branched head horn and short, sharp thoracic horn that they use to pry rival males away from sap sites that attract females. Small minor males have short head and thoracic horns, yet they engage in direct combats with other males just as readily as major males, and do not fight in qualitatively different ways (Hongo 2003). Even though minor males engage in sneak-like behaviors, major males also sneak copulations, and the only male that is known to have successfully mated after sneaking was a major male (Hongo 2007). J Insect Behav (2013) 26:51–56 DOI 10.1007/s10905-012-9334-8