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Kitowski, Ignacy
Inter-sexual differences in foraging tactics of Marsh Harriers (Circus aeruginosus) were studied in southeastern Poland. Observed individuals preferred foraging in regularly mowed meadows and fields and avoided feeding over burned meadows. The basic technique of foraging was cruising flights (90.2%, N = 724). However, the use of hovering flights was ...
Baužienė, Vilma
Precopulatory and mating behaviour of stenogamous black fly species (Diptera: Simuliidae) Simulium lineatum (Meigen, 1984) was investigated under natural conditions. Polygynous males were found as single individuals or assembled in small aggregations (1.8 ± 1.1 individuals on average) on calami (above water height up to 50 cm) or in larger ...
Byers John A - - 2013
The plant bugs Lygus hesperus, Lygus lineolaris, and Lygus elisus (Hemiptera: Miridae) are major pests of many agricultural crops in North America. Previous studies suggested that females release a sex pheromone attractive to males. Other studies showed that males and females contain microgram amounts of (E)-4-oxo-2-hexenal, hexyl butyrate, and (E)-2-hexenyl ...
Mozūraitis Raimondas - - 2013
Analysis of the sex pheromone gland of virgin Synanthedon scoliaeformis females by gas chromatography/mass spectrometry revealed six compounds structurally related to sex pheromone components of other clearwing moths: (E,Z)-2,13-octadecadienyl acetate (E2,Z13-18:OAc), (E,Z)-2,13-octadecadienol, octadecanol acetate, octadecanol, (Z,Z)-3,13-octadecadienyl acetate (Z3,Z13-18:OAc), and (Z)-13-octadecenyl acetate. Trapping tests demonstrated that E2,Z13-18:OAc is the sex pheromone ...
Ozaydın T - - 2013
We attempted to characterize the cytochemical staining patterns of leukocytes and to determine the percentages of alpha-naphthyl acetate esterase (ANAE) and acid phosphatase (ACPase) positive lymphocytes in peripheral blood of thoroughbred foals at different ages. Blood samples were obtained from the jugular veins of 60 healthy thoroughbred foals, 1 day, ...
Ramanathan Rohit - - 2013
BACKGROUND: Chitotriosidase (ChT) is secreted by chronically activated macrophages in Gaucher's disease. We hypothesize that circulating levels of ChT are altered with normal aging, reflecting age-related chronic macrophage activation. Potential sources that might contribute to altered levels were assessed by measuring systemic levels of ChT are α-naphthyl acetate esterase, a ...
Yang Chang Yeol - - 2013
The sex pheromone of Stathmopoda auriferella (Walker), an important pest of kiwifruit in Korea, was studied. Two candidate pheromone components detected in the gland extracts of females were identified as (E)-5-hexadecenyl acetate (E5-16:OAc) and (E)-5-hexadecenol (E5-16:OH) in a ratio of 75:25 by mass spectral analysis of natural pheromone components and ...
Myojin Tomoya - - 2012
Mesothelioma is a malignancy with poor prognosis. It is chiefly caused by asbestos exposure and its symptoms can occur about 30-50 yr after the initial exposure. This study aims to predict the future trends in mesothelioma mortality in Japan using a method that is an alternative to the age-cohort model. ...
La Vecchia Carlo - - 2012
The model of asbestos-related mesothelioma implies that the time since first exposure (latency) is the key determinant of subsequent risk. The role of recent exposure or stopping asbestos exposure, if any, is, however, open to discussion. A literature review was conducted to the end of 2010. In a cohort of ...
Riaz Sharma P - - 2012
We estimated the past and future age-standardised incidence rates of mesothelioma by birth cohort and by period of diagnosis in South East England. We extracted data on patients diagnosed with mesothelioma (International Classification of Diseases-10 C45) between 1960 and 2009 from the Thames Cancer Registry. We calculated the age-standardised incidence ...
South Adam - - 2011
Although the primary function of mating is gamete transfer, male ejaculates contain numerous other substances that are produced by accessory glands and transferred to females during mating. Studies with several model organisms have shown that these substances can exert diverse behavioural and physiological effects on females, including altered longevity and ...
Cerný O - - 2011
The section of habitat used by particular bloodsucking insects when seeking bloodmeals may influence the spectrum of hosts to which they have access and consequently the diseases they transmit. The vertical distribution of ornithophilic bloodsucking Diptera (Culicidae, Simuliidae and Ceratopogonidae) was studied using bird-baited traps set at both ground and ...
Thomas Melissa L - - 2011
Males of many species choose their mate according to the female's reproductive status, and there is now increasing evidence that male fitness can depend on this discrimination. However, females will also aim to regulate their mating activity so as to maximize their own fitness. As such, both sexes may attempt ...
Fedigan Linda Marie - - 2011
Many factors have been hypothesized to affect the size and adult sex ratios of primate groups and these, in turn, have been argued to influence birth rates. Using park-wide census data collected on a population of capuchins over a 25-year period, we examined whether group size and adult sex ratio ...
Muniz Laura - - 2010
Theory and a growing body of empirical evidence suggest that higher ranking males experience reproductive advantages in group-living mammals. White-faced capuchins (Cebus capucinus) exhibit an interesting social system for investigating the relationship between dominance and reproductive success (RS) because they live in multimale multifemale social groups, in which the alpha ...
Conrad Taina - - 2010
Females are often thought to use several cues and more than one modality in selection of a mate, possibly because they offer complementary information on a mate's suitability. In the red mason bee, Osmia rufa, we investigated the criteria a female uses to choose a mating partner. We hypothesized that ...
Hirsch Ben T - - 2011
The ring-tailed coati (Nasua nasua) is the only coati species in which social groups contain an adult male year round, although most males live solitarily. We compared reproductive success of group living and solitary adult male coatis to determine the degree to which sociality affects reproductive success. Coati mating is ...
Riehl Christina - - 2011
The greater ani (Crotophaga major), a Neotropical cuckoo, exhibits an unusual breeding system in which several socially monogamous pairs lay eggs in a single nest and contribute care to the communal clutch. Cooperative nesting is costly-females compete for reproduction by ejecting each other's eggs-but the potential direct or indirect fitness ...
Galipaud Matthias - - 2011
Precopulatory mate guarding (PCMG) is generally assumed to be costly for both sexes. However, males may gain by displaying long-lasting mate guarding under strong male-male competition. Surprisingly, the potential for females to benefit from being held by males has been largely overlooked in previous studies. In Gammarus pulex, an amphipod ...
Mirimin Luca - - 2011
The analysis of stranding events and the application of molecular markers can be powerful tools to study cryptic biological aspects of delphinid species that occur mainly in open ocean habitat. In the present study, we investigated nuclear and mitochondrial genetic variability of Atlantic white-sided dolphins that stranded from 1990 to ...
Longpre Kristy M - - 2011
In a promiscuous species like the domestic goat (Capra hircus), in which maternal investment is greater than paternal investment, a female may mate selectively with a more-fit male to improve her reproductive fitness. Testosterone (T) controls a large suite of male-typical behaviors and morphological characteristics. High T concentrations may be ...
Olsson Mats - - 2011
A changing climate is expected to have profound effects on many aspects of ectotherm biology. We report on a decade-long study of free-ranging sand lizards (Lacerta agilis), exposed to an increasing mean mating season temperature and with known operational sex ratios. We assessed year-to-year variation in sexual selection on body ...
Edward Dominic A - - 2011
Precise estimates of costs and benefits, the fitness economics, of mating are of key importance in understanding how selection shapes the coevolution of male and female mating traits. However, fitness is difficult to define and quantify. Here, we used a novel application of an established analytical technique to calculate individual- ...
Ostner Julia - - 2011
In polygynous mammals, where males compete over access to females, the potential of males to monopolize reproductive females largely depends on the spatio-temporal distribution of reproductive females. We investigated mechanisms of male reproductive competition and its hormonal basis in a cercopithecine species with reduced contest potential owing to female reproductive ...
Drayton J M - - 2011
Male field crickets produce two acoustic signals for mating: advertisement calls and courtship calls. While the importance of advertisement calling in mate attraction is well understood, the function of courtship calling is less clear. Here, we tested if the courtship call of male crickets Teleogryllus commodus signals aspects of male ...
Honkavaara J - - 2011
Character displacement is a process by which interactions between two species that exhibit similar traits, results in geographical patterns of trait divergence in one or both species. These traits evolve to reduce costs of interspecific interactions in sympatry and thus differ from their condition in allopatry. In male damselflies Calopteryx ...
Kekäläinen Jukka - - 2010
Secondary sexual characters are often expressed in both sexes (mutual ornamentation), but are less often studied simultaneously. We studied the adaptive signaling function of male and female ornamentation in a mutually ornamented fish, the whitefish Coregonus lavaretus. In an experimental design in which nongenetic environmental effects were minimized, we found ...
Wolovich Christy K - - 2010
In socially monogamous species, mate-guarding could be a reproductive strategy that benefits both males and females, especially when males contribute to parental care. By actively guarding mates, males may reduce their chances of being cuckolded, whereas females that mate-guard may reduce the likelihood that their mates will desert them or ...
Gladbach Anja - - 2010
Although studies on the evolution and function of female ornaments have become more numerous in the last years, the majority of these studies were carried out in cases where female ornaments were a smaller and duller version of the ornaments found in males. There are substantially fewer studies on species ...
Jan Oettler - - 2010
Alternative reproductive tactics are often associated with discontinuous variation in morphology but may evolve independent from each other. Based on life-history data and a phylogeny we examine how male morphology and reproductive behavior are linked in the evolution of the ant genus Cardiocondyla. Wingless Cardiocondyla males engage in lethal fighting ...
Sullivan-Beckers Laura - - 2010
Selection on advertisement signals arises from interacting sources including female choice, male-male competition, and the communication channel (i.e., the signaling environment). To identify the contribution of individual sources of selection, we used previously quantified relationships between signal traits and each putative source to predict relationships between signal variation and fitness ...
Yu Tong Lei - - 2010
The large-male mating advantage and size-assortative mating are two different size-based patterns, which deviate from random mating in toads. These two pairing patterns may arise due to female choice, male-male competition, male choice, or a combination of these. This study investigated the mating system of Minshan's toad (Bufo minshanicus) from ...
Bonisoli-Alquati Andrea - - 2011
Evidence is accumulating that sex steroids in the eggs, besides affecting progeny phenotype and behavior in the short term, also have enduring effects until adulthood, when they may translate into differences in reproductive strategies and success. Maternal steroids transfer may therefore affect both agonistic behavior and mate choice decisions, either ...
Ota Kazutaka - - 2010
Despite the wide prevalence of alternative reproductive tactics, little attention has been paid to why reproductively parasitic males are so small. In this study, we tackled this issue in a shell-brooding fish Lamprologus callipterus. Sneaky 'dwarf males' of this fish remain much smaller than bourgeois conspecifics throughout their life and ...
White Joël - - 2010
Ecology Letters (2010) 13: 1515-1524 ABSTRACT: Sexual transmission is an important mode of disease propagation, yet its mechanisms remain largely unknown in wild populations. Birds comprise an important model for studying sexually transmitted microbes because their cloaca provides a potential for both gastrointestinal pathogens and endosymbionts to become incorporated into ...
Morehouse Nathan I - - 2010
Color ornaments are often viewed as products of countervailing sexual and natural selection, because more colorful, more attractive individuals may also be more conspicuous to predators. However, while evidence for such countervailing selection exists for vertebrate color ornaments (e.g., Trinidadian guppies), similar studies have yet to be reported in invertebrates. ...
Bacelar Flora S - - 2011
tlsb-1%Males are often the 'sicker' sex with male biased parasitism found in a taxonomically diverse range of species. There is considerable interest in the processes that could underlie the evolution of sex-biased parasitism. Mating system differences along with differences in lifespan may play a key role. We examine whether these ...
Ribeiro Pablo D - - 2010
Fiddler crabs show two different mating modes: either females search and crabs mate underground in male burrows, or males search and crabs mate on the surface near female burrows. We explored the relationship between crab density, body size, the searching behavior of both sexes, and the occurrence of both mating ...
Karlsson K - - 2010
Ecological factors can have profound effects on mating system and mating behaviour. We investigated the effect of altered ecological conditions, following colonization of a novel habitat, on precopulatory mate guarding in a freshwater isopod (Asellus aquaticus). This isopod occurs in two different ecotypes, which coexist within several different lakes in ...
Tolle Amanda E - - 2011
The handicap hypothesis proposes that male signals provide reliable information to females because only males of high condition provide high-quality mating benefits and can afford the costs of producing attractive signals. In the context of direct benefits, the handicap hypothesis predicts that benefit quality and signal attractiveness will positively covary ...
Khokhlova Irina S - - 2010
The quality of offspring produced by parent fleas (Xenopsylla ramesis) fed on either male or female rodent hosts (Meriones crassus) was studied. The emergence success, duration of development, resistance to starvation upon emergence and body size of the flea offspring were measured. It was predicted that offspring of fleas produced ...
Takeuchi Tsuyoshi - - 2010
The mate-locating behavior of male butterflies has been classified into two major types, territorial and patrolling. Territorial males defend a specific site, whereas patrolling males fly around a wider area without having to defend a site. In this study, I investigated the use of these tactics by males of the ...
Sellanes Carolina - - 2010
Cryptoblabes gnidiella Milliére (Lepidoptera: Pyralidae) is an economically important exotic pest of vineyards in Southern Brazil and Uruguay. The sex pheromone of C. gnidiella was identified as a mixture of (Z)-11-hexadecenal and (Z)-13-octadecenal, and has been used to monitor populations of this pest in Israel. The development of mating disruption ...
Borkowska Anetta - - 2011
Variation of reproductive success, an important determinant of the opportunity for sexual selection, is an outcome of competition within one sex for mating with members of the other sex. In promiscuous species, males typically compete for access to females, and their reproductive strategies are strongly related to the spatial distribution ...
Matsumoto-Oda Akiko - - 2011
Estrous cycle asynchrony likely functions to elevate individual females' sexual attractiveness during female mate choice. Female chimpanzees show physiological estrus as anogenital swelling. Copulations are concentrated during the period of maximal tumescence, which is called the estrous period. A group of female chimpanzees in Mahale Mountains National Park, Tanzania, was ...
Giraudeau M - - 2011
The differential allocation hypothesis predicts that females modify their investment in a breeding attempt according to its reproductive value. One prediction of this hypothesis is that females will increase reproductive investment when mated to high-quality males. In birds, it was shown that females can modulate pre-hatch reproductive investment by manipulating ...
Fanson Kerry V - - 2010
Canada lynx are listed as a threatened species in the contiguous US. Understanding the reproductive characteristics (i.e., mating system, behavior, physiology) of a species is useful for ensuring effective in situ and ex situ management plans. The goal of this study was to describe patterns of androgen expression in both ...
Jordan L A - - 2010
The reproductive effort that a male directs to a familiar female declines over time, suggesting decreasing marginal returns. But is this diminishing returns a function of increasing reproductive costs or decreasing benefits of sustained effort? Here, we use the restoration of male reproductive effort with unfamiliar females to differentiate the ...
Ceballos Sara - - 2010
Sexual selection is potentially important in marine zooplankton, presumably the most abundant metazoans on earth, but it has never been documented. We examine the conditions for sexual selection through mate choice and describe mating preferences in relation to size in a marine zooplankter, the pelagic copepod Acartia tonsa. Males produce ...
Gibson K Nicole - - 2010
I investigated the mating system and male mating tactics for a population of wild spider monkeys (Ateles belzebuth chamek), to identify the behaviors males used to achieve and maintain access to sexually receptive females, and to examine if some males used more tactics than other males and/or had differential access ...
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