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We studied calls of three sandpiper species to document species' similarities and differences. We hypothesized that functionally different calls would differ in degree of divergence. We studied two nuptial calls (complex 'Song' and rhythmically repeated aerial call, RRC) of males, and a general-purpose call ('alarm' trill, AT) given by parents of both sexes in the presence of humans and other potential predators, in great knot, Calidris tenuirostris (Horsfeld, 1821); surfbird, Calidris virgata (Gmelin, 1789); and red knot, Calidris canutus (Linnaeus, 1758). Calls diverged unevenly across species--RRCs and Song diverged the most and ATs the least. Vocalizations of great knot and surfbird were most similar to one another, in agreement with a recently proposed phylogeny Despite species differences in single acoustic traits, calls were evolutionarily conservative at higher structural levels, such as rhythmic temporal delivery of RRCs and harmonic structure (e.g., the fundamental frequency was suppressed in some call types). Some acoustic qualities that differed across species were similar across call types within species (e.g., tonality in red knot calls). Trait similarity across different calls suggests that a species' calls cannot evolve independently of one another: common mechanisms of vocal production across different calls may impede differentiation within a species' repertoire. Key words: evolutionary constraints, evolutionary rates, phylogeny, sandpiper, sexual selection, vocalization, Introduction Comparative studies marked the emergence of the study of animal behaviour (Lorenz 1941; Tinbergen 1959) and continue to contribute to our understanding of behavioural evolution (Ord and Martins 2010; [...]

Mating and egg laying are tightly cooordinated events in the reproductive life of all oviparous females. Oviposition is typically rare in virgin females but is initiated after copulation. Here we identify the neural circuitry that links egg laying to mating status in Drosophila melanogaster. Activation of female-specific oviposition descending neurons (oviDNs) is necessary and sufficient for egg laying, and is equally potent in virgin and mated females. After mating, sex peptide--a protein from the male seminal fluid--triggers many behavioural and physiological changes in the female, including the onset of egg laying.sup.1. Sex peptide is detected by sensory neurons in the uterus.sup.2-4, and silences these neurons and their postsynaptic ascending neurons in the abdominal ganglion.sup.5. We show that these abdominal ganglion neurons directly activate the female-specific pC1 neurons. GABAergic ([gamma]-aminobutyric-acid-releasing) oviposition inhibitory neurons (oviINs) mediate feed-forward inhibition from pC1 neurons to both oviDNs and their major excitatory input, the oviposition excitatory neurons (oviENs). By attenuating the abdominal ganglion inputs to pC1 neurons and oviINs, sex peptide disinhibits oviDNs to enable egg laying after mating. This circuitry thus coordinates the two key events in female reproduction: mating and egg laying. Neuron-tracing and labelling experiments in Drosophila females reveal the neural circuitry that coordinates mating and egg laying, and the role of sex peptide from male seminal fluid in triggering these neurons., Author(s): Fei Wang [sup.1] , Kaiyu Wang [sup.1] , Nora Forknall [sup.1] , Christopher Patrick [sup.1] , Tansy Yang [sup.1] , Ruchi Parekh [sup.1] , Davi Bock [sup.1] [sup.3] , [...]

A detailed understanding of animal movement behavior is fundamental to effective conservation and management. Within populations, a diversity of movement strategies can be displayed in search of critical resources, and these strategies are influenced by multiple interacting factors related to individuals and the environment. Mating partners are one critical resource that often serves as a prominent selective force shaping movement during mating seasons. For many large-bodied snakes, such as pit vipers (Viperidae: Crotalinae), male mate-searching movements are the primary determinant of mate location success. During this time, males incur significant risks associated with elevated movement. In an increasingly human-modified world, this often includes more frequent interactions with anthropogenic landscape features, such as roadways. A recent range-wide status assessment for Timber Rattlesnakes (Crotalus horridus) identified roadways among the leading threats to population persistence. More narrowly, roads are implicated in recent declines for C. horridus populations in the Piedmont ecoregion of Georgia, USA. Before effective mitigation strategies can be developed, it is critical to identify behavioral mechanisms that mediate the relative risk that roads pose to populations and individuals. Even in the absence of significant road mortality, sub-lethal effects of roads have been well documented for other wildlife but remain largely untested in snakes. In order to fill these gaps and better inform conservation, I propose an integration of radio telemetry and accelerometry to quantify the effects of proximity to roads and road interaction frequency on mate searching movements and mate location success in C. horridus from the Georgia Piedmont., Recommended Citation Authors Elizabeth J. Noble (*), Georgia College and State University, Milledgeville, GA 31061 Follow Anna F. Tipton, University of Texas, El Paso, Texas 79968 Follow Dominic L. DeSantis, [...]

A detailed understanding of animal movement behavior is fundamental to effective conservation and management. Within populations, a diversity of movement strategies can be displayed in search of critical resources, and these strategies are influenced by multiple interacting factors related to individuals and the environment. Mating partners are one critical resource that often serves as a prominent selective force shaping movement during mating seasons. For many large-bodied snakes, such as pit vipers (Viperidae: Crotalinae), male mate-searching movements are the primary determinant of mate location success. During this time, males incur significant risks associated with elevated movement. In an increasingly human-modified world, this often includes more frequent interactions with anthropogenic landscape features, such as roadways. A recent range-wide status assessment for Timber Rattlesnakes (Crotalus horridus) identified roadways among the leading threats to population persistence. More narrowly, roads are implicated in recent declines for C. horridus populations in the Piedmont ecoregion of Georgia, USA. Before effective mitigation strategies can be developed, it is critical to identify behavioral mechanisms that mediate the relative risk that roads pose to populations and individuals. Even in the absence of significant road mortality, sub-lethal effects of roads have been well documented for other wildlife but remain largely untested in snakes. In order to fill these gaps and better inform conservation, I propose an integration of radio telemetry and accelerometry to quantify the effects of proximity to roads and road interaction frequency on mate searching movements and mate location success in C. horridus from the Georgia Piedmont., Acknowledgements GCSU Dept. of Biological and Environmental Sciences Recommended Citation Authors Elizabeth J. Noble, Georgia College and State University, Milledgeville, GA 31061 Follow Anna F. Tipton, University of Texas, El [...]

It has now been found that mothers of a species of frog affect the behaviour of their offspring -- influencing female mating preferences and aggression between males. Such behaviours might lead to the formation of new species. Maternal colour affects mate choice and aggression of offspring., Author(s): Machteld Verzijden Author Affiliations: Leapfrog to speciation boosted by mother's influence The ability of a species to maintain many different types of individual in a population, known as polymorphisms, [...]

Social monogamy is characterized by long-term pair-bonds, but there is extensive variation among socially monogamous species in the timing of pair formation, the extent to which pair-mates associate throughout the year, the duration of pair-bonds, and the frequency with which pair-bonds are dissolved while both partners are living. We studied these aspects of social monogamy in kit foxes (Vulpes macrotis) at 1 urban and 2 nonurban sites. Behavior was similar across sites despite differences in ecological conditions. Pair formation occurred throughout the year, often within a month after the loss of a mate. Pair-mates associated throughout the year. Some pairs remained associated for more than 1 breeding season. Death of a pair-mate was the most common reason for the dissolution of a pair (14 of 16 cases). Two pairs dissolved while both partners were still living: 1 due to abandonment by a male of his pair-mate and territory and 1 due to displacement of a male by another male. These characteristics of social monogamy in kit foxes may be related to year-round territoriality, and may optimize individual fitness by enhancing survival and ultimately reproductive success. Key words: kit fox, monogamy, pair-bond, Vulpes macrotis

This study explored the constructs of mating tactics and mating strategies. These constructs are conceptually related but distinct. In current research, the measurement of one of these constructs often is [...]

Conspicuous displays of consumption and benevolence might serve as 'costly signals' of desirable mate qualities. If so, they should vary strategically with manipulations of mating-related motives. The authors examined this possibility in 4 experiments. Inducing mating goals in men increased their willingness to spend on conspicuous luxuries but not on basic necessities. In women, mating goals boosted public--but not private--helping. Although mating motivation did not generally inspire helping in men, it did induce more helpfulness in contexts in which they could display heroism or dominance. Conversely, although mating motivation did not lead women to conspicuously consume, it did lead women to spend more publicly on helpful causes. Overall, romantic motives seem to produce highly strategic and sex-specific self-presentations best understood within a costly signaling framework. Key words: costly signaling, altruism, conspicuous consumption, mating goals, self-presentation

Empirical model of effects of assortative mating and full-time employment on labor force participation in employer-based health insurance schemes is presented.

The evolution, life styles and the reproductive strategies of yeasts, particularly S. cerevisiae, are discussed. The analysis has shown that a high level of plasticity is inherent in the yeast breeding system, which allows genetic variation of the breeding behavior in accordance with the needs imposed by the environment.

A gal4-containing enhancer-trap called C309 was previously shown to cause subnormal courtship of Drosophila males toward females and courtship among males when driving a conditional disrupter of synaptic transmission ([shi.sup.TS]). We extended these manipulations to analyze all features of male-specific behavior, including courtship song, which was almost eliminated by driving [shisup.TS] at high temperature. In the context of singing defects and homosexual courtship affected by mutations in the fru gene, a tra-regulated component of the sex-determination hierarchy, we found a C309/[tra.sup.F] combination also to induce high levels of courtship between pairs of males and 'chaining' behavior in groups; however, these doubly transgenic males sang normally. Because production of male-specific FR[U.sup.M] protein is regulated by TRA, we hypothesized that a fru-derived transgene encoding the male (M) form of an Inhibitory RNA ([fru.sup.MIR]) would mimic the effects of [tra.sup.F]; but C309/[fru.sup.MIR] males exhibited no courtship chaining, although they courted other males in single-pair tests. Double-labeling of neurons in which GFP was driven by C309 revealed that 10 of the 20 CNS clusters containing FR[U.sup.M] in wild-type males included coexpressing neurons. Histological analysis of the developing CNS could not rationalize the absence of [tra.sup.F] or [fru.sup.MIR] effects on courtship song, because we found C309 to be coexpressed with FR[U.sup.M] within the same 10 neuronal clusters in pupae. Thus, we hypothesize that elimination of singing behavior by the C309/[shi.sup.TS] combination involves neurons acting downstream of FR[U.sup.M] cells reproductive behavior | C309 enhancer trap | [shi.sup.TS] transgene | [tra.sup.F] transgene | inhibitory fru RNA transgene

The genetic basis for breakdown in self-compatibility (SI) systems was studied to examine the causes and genetic consequences of changes in the breeding system. The study surveyed the variation in selfing rates in rare species Arabidopsis lyrata (Brassicaceae), that is often considered as obligately out-crossing species.

A mathematical model is used to show that monogyny as a means of increasing paternity is favored when the sex ratio is male biased but not necessarily by high search costs. Various empirical studies are presented to support the importance of male-biased sex ratio for the evolution of monogyny.

The relative rate of evolution of pre-and postzygotic reproductive isolation using eight populations of the sexually dimorphic stalk-eyed flies Cyrtodiopsis dalmanni and Cyrtodiopsis whitei is tested. To measure the reproductive isolation, one male and three female flies were housed from within and between these populations in replicate cages and then recorded mating behavior, sperm transfer, progeny production, and hybrid fertility.

A study that focuses on possible relationships between occurrences of sexually dimorphic visual traits in male anthropoids and the types of mating systems that characterize the various species and genera is illustrated. Striking secondary sexual traits, such as brightly colored sexual skin, capes of hair, beards, and other facial adornments occur in adult males of many anthropoid primate species.

To better understand the genetic bases of postmating responses in Drosophila melanogaster females, we screened a collection of P{GS} insertion lines and identified two insertions in sarah (sra), whose misexpression in the nervous system induced high levels of ovulation in virgins. The gene sra encodes a protein similar to human Down syndrome critical region 1 (DSCR1). The ovulation phenotype was reproduced in transgenic virgins expressing UAS-sra in the nervous system. The flies also extruded the ovipositor toward courting males as seen in wild-type mated females, supporting the notion that ovulation and behavioral patterns are physiologically coupled. The sra insertions were found to be hypomorphic alleles with reduced expression levels. Females homozygous for these alleles show: (1) spontaneous ovulation in virgins, (2) sterility with impaired meiotic progression, and (3) compromised postmating responses with lower ovulation level, higher remating rate, and shorter period for restoration of receptivity. No obvious defects were observed in the homozygous males. The gene sra is predominantly expressed in oocytes, nurse cells, and the nervous system. Taken together, these results indicate that the expression level of sra is critical for ovulation and female courtship behavior, including their postmating changes.

Two sibling species of tephritid fruit fly, Bactrocera tyroni and Bactrocera neohumeralis, are differentiated by their time of mating, which is genetically determined and requires interactions between the endogenous circadian clock and light intensity. The cryptochrome (cry) gene, a light-sensitive component of the circadian clock, was isolated in the two Bactrocera species. The putative amino acid sequence is identical in the two species. In the brain, in situ hybridization showed that cry is expressed in the lateral and dorsal regions of the central brain where PER immunostaining was also observed and in a peripheral cell cluster of the antennal lobes. Levels of cry mRNA were analyzed in whole head, brain, and antennae. In whole head, cry is abundantly and constantly expressed. However, in brain and antennae the transcript cycles in abundance, with higher levels during the day than at night, and cry transcripts are more abundant in the brain and antennae of B. neohumeralis than in that of B. tryoni. Strikingly, these results are duplicated in hybrid lines, generated by rare mating between B. tryoni and B. neohumeralis and then selected on the basis of mating time, suggesting a role for the cry gene in the mating isolation mechanism that differentiates the species.

I investigated the causes and consequences of adult breeding-site fidelity, territory fidelity, and natal philopatry in Willow Flycatchers (Empidonax traillii) in southeastern Oregon over a 10-year period, testing the general hypothesis that fidelity and dispersal distances are influenced by previous breeding performance. Willow Flycatchers adhered to the generally observed tendencies of passerine birds for low natal philopatry and high breeding-site fidelity. Site fidelity (return to the study area) of adult males (52.0%) and females (51.3%), and median dispersal distances between seasons (16 m vs. 19 m) were similar. Previous breeding performance and residency (age-experience), but not study-site quality, explained site fidelity in females. Site fidelity of females rearing 4-5 young (64.4%) exceeded that of unsuccessful females (40.0%), breeding dispersal was less (successful: 15 m; unsuccessful: 33 m), and novice residents were more site-faithful than former residents. Probability of site fidelity was higher for previously successful females (odds ratio = 4.76), those with greater seasonal fecundity (odds ratio = 1.58), novice residents (odds ratio = 1.41), and unparasitized females (odds ratio - 2.76). Male site fidelity was not related to residency, site quality, or previous breeding performance. Territory fidelity (return to the previous territory) in females was best explained by previous breeding performance, but not by site quality or residency. Previously successful females were more likely to return to their territory of the previous season than either unsuccessful (odds ratio = 14.35) or parasitized birds (odds ratio = 6.38). Male territory fidelity was not related to residency, site quality, or previous breeding performance. Natal philopatry was low (7.8%) and similar for males and females. Site quality appeared to influence philopatry, given that no birds reared at a low-quality study site returned there to breed, and birds reared there dispersed farther than birds reared at two other study sites. My results partially support the hypothesis that site fidelity is an adaptive response: (1) previously successful females that switched territories underperformed those that did not switch (P = 0.01); and (2) previously unsuccessful females that switched territories outperformed those that did not switch, but not significantly (P = 0.22). Received 24 January 2003, accepted 6 April 2004.

A robust PCR-based method suitable for the identification of mating type in several Fusarium species with no known sexual stage was developed. This PCR method facilitates the recognition of potentially compatible strains that could be used in crossing experiments to obtain telemorphic structures.

Recent work on wild birds has revealed the importance of sperm competition as a source of sexual selection, but behavioral and paternity studies have previously provided only indirect evidence for mechanisms of sperm competition in wild birds. In a field study of collared flycatchers Ficedula albicollis we used a previously uncharacterized method to determine the frequency and timing of extra-pair inseminations. By counting the number of sperm trapped on the perivitelline layer of eggs, we determined the timing of inseminations and estimated, on a day-to-day basis, the amount of sperm females stored. Our results showed that female collared flycatchers preferentially engaged in extra-pair copulations when mated to an unattractive male with a small white forehead patch. These copulations were timed for the middle part of their fertile period, at least 2 days after the last within-pair insemination. Although the mean number of extra-pair insemination events was only 1.33 per cuckolding female, the ratio between the number of sperm from extra-pair and pair inseminations was at least 5 to 1. Thus a single, well timed extra-pair insemination caused by female behavior could greatly bias fertilization probability in favor of an attractive extra-pair male. Our results suggest a possible behavioral mechanism for female control of sperm competition.

Research demonstrates that female crickets prefer long chirp calls to short chirps from male crickets with fair amount of variation across populations. Furthermore, a mismatch between the length of long chirp and female preferences is observed with long chirps being prefereed by acoustically oriented female parasitoids.

The life-history of Cynopterus sphinx exhibits a disproportionately short sexual maturation period leading to a lessened influence of the polygynous mating on the genetically effective population size scaled to adult population. Data indicate that male breeding turnover results in a broader sampling of adult male gamete pool.

The reproductive biology in the grass goby fishes encompasses alternating mating tactics. This is indicated in the field and in the trail sperm content and sperm production in males of different sizes.

The sexual behavior of the North American plethodontid salamander, Desmognathus ocoee, was studied to determine whether courtship displays by males evolve through sexual selection of the females. The mating success for individual males varied from 14% to 69% relative to multiple potential mates for different encounters. The males' abilities to arouse or convince females to copulate were proposed to account for the differences in male mating success rates.

Fledgling production in a population of monogamous and polygynous males Passerculus sandwichensis or Savannah sparrows were analyzed to determine the role of polygyny on male reproductive performance. Multilocus DNA fingerprinting analysis of fledglings in a population of monogamous and polygynous male sparrows indicated the role of polygyny in increasing male reproductive success. Furthermore, paternity costs were absent in Savannah sparrows due to simultaneous polygyny that was exhibited by male sparrows.

The relationship between male morphology and female mate selection was analyzed in natural populations of male willow ptarmigan, Lagopus lagopus, to determine the effects of polygyny to male willow ptarmigans. Analysis of pairing status in male Lagopus lagopus indicated the role of polygyny in increasing reproductive success compared to monogamous males. Furthermore, pairing status in male willow ptarmigan was dependent on their ability to defend a large territory, age and size.

The mechanisms of mate selection by the female drumming wolf spider, Hygrolycosa rubrofasciata, were analyzed to determine the effects of varying male acoustic courtship signalling, rate and volume. Analysis of female mate selection in drumming wolf spiders indicated the preference of female spiders for active male drumming, calling rate and volume. Furthermore, active male drumming is indicative of male quality in Hygrolycosa rubrofasciata.

The relationship between male color pattern evolution and female mate selection or preference was analyzed in natural populations of Poecilia reticulata guppies. Analysis of female preferences in relation to male colour patterns in Poecilia reticulata indicated the the absence of correlation between the expression of specific male characteristics compared to female mate preference. Furthermore, the expression of specific color preferences in male guppies did not match with specific female preferences.

The pre-copulatory behavior of the Bearded tit, Panurus biarmicus, was analyzed during the breeding season to determine the motivation behind female resistance behavior. Analysis of female resistance behavior in monogamous Bearded tits during chase-flights and copulations indicated a high frequency of chase-flights in females of high quality males compared to low quality males. Furthermore, female pre-copulatory behavior promoted sperm competition among male Bearded tits.

The mechanics of mate selection by gravid females was analyzed in natural populations of the sand goby, Pomatoschistus minutus. Analysis of mate selection in marine sand gobies indicated the presence of random mating and threshold-criterion tactics during the early breeding season. Female Pomatoschistus minutus also select males depending on their physical characteristics regardless of their nests. Furthermore, female sand gobies exhibited long durations of male sampling and selection prior to mating.

The hotspot hypothesis indicates that cluster formation by male avians that attract females (leks) is influenced by the distribution patterns of the female or female density. Analysis of the relationship between leks distribution and female distribution patterns in ochre-bellied flycatchers from neotropic wetland forests indicated the validity of the hotspot hypothesis. Furthermore, the location of leks depend on female traveling routes and feeding areas during the breeding season.

Variations in protein content of diet affect the attractiveness of scents in meadow voles, Microtus pennsylvanicus. Both males and females exhibit preference for odors of opposite-sex conspecifics fed with a 15% or a 25% protein content diet as compared to those fed with a 9% protein content diet. The protein content influences the attractiveness of odors from anogenital area, faeces and urine. High quality diet quality enhances the secondary sexual characteristics and influences the mate selection decisions.

The sexual-asexual mating complex of sailfin mollies, Poecilia latipinna, and Amazon mollies, P. formosa, depends on the close proximity of aggregated individuals or shoals. P. formosa is gynogenetic and is inseminated by male P. latipinna. The females are unable to discriminate species which results in mate copying. Females of both the species prefer associating with a conspecific rather than a heterospecific group. However, they prefer to associate with a larger heterospecific group rather than a smaller conspecific one.

In species that raise several broods within a breeding season, mate replacement may be costly to males if breeding success is low for newly formed pairs. Alternatively, males could benefit from mate replacement if the new female is in better physical condition than the previous mate. Female House Sparrows (Passer domesticus) experimentally handicapped during their first breeding attempt were replaced more frequently than control females. Among females that changed mates, handicapped females remated less successfully than did control females. Relative to control males, males that mated with handicapped females took longer to produce a second clutch. Males that changed mates had shorter relaying intervals but raised fewer fledglings in the following breeding attempt than males that retained mates. These results suggests that mate replacement is costly to males. Courtship rate was positively correlated with male badge size, an indicator of male quality and status, but it was not correlated with any indicator of female quality or female reproductive investment. Increased levels of courtship between two breeding attempts correlated with more rapid laying by replacement females but did not affect the probability of mate replacement or the relaying interval of the original mates. These results suggest that male courtship between clutches may function as a time-saving mechanism when mate replacement occurs. Received 25 September 1995, accepted 22 February 1996.

A study conducted to evaluate the capability of female aggression to shape the mating pattern of the pied flycatcher shows that aggression by primary females is ineffective in preventing further matings of males as they give up easily if the prospecting females are willing to stay. The hypothesis that the aggression by the primary female prevents the settlement of a secondary female to a close second territory, is a less plausible explanation for polyterritoriality in the pied flycatcher. The males with close second territory are found to have reduced mating success.

A study of the videotaping of responses of male and female Drosophila melanogaster to male courtship songs showed that females and males were differentially influenced by different songs. Males became inactive while responding to the white noise whereas experimental conditions elicited locomotion and courtship chases. Females responded to the signals reaching the sound-level threshold and showed discrimination between different songs.

Research conducted in Chironomus plumosus midges find that the mating success depends on the fluctuating asymmetry in the male characters, and the success of symmetrical male is due to his improved aerobatic ability. Male Chironomus plumosus, successful at acquiring mates, show lower levels of fluctuating asymmetry in the length of wing than their rivals. Small males are found to be more successful in acquiring mates.

Male thirteen-lined ground squirrels, Spermophilus tridecemelineatus, possess the capacity to anticipate when some of the females can become fertilizable and relocate individual females. Male perceptiveness and spatial ability is favored by competitive mate searching. The interaction between male and female species, observed for a day, showed that male reaction to the removal of a female was based on her reproductive state. Males searched more extensively for females who were in oestrus.

A study of the preferences of the oestrous females for the odor of the adult house mice revealed that the oestrous females preferred the odor of sons of well nourished females and heavier males. Thus, the sons of undernourished mothers might not be chosen as mates as frequently. They might also have less reproductive potential. The findings suggest that the skewed secondary sex ratios of undernourished female mice are adaptive.