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1.
J Insect Sci ; 21(2)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33861348

RESUMO

The potential of the parasitoid Psyllaephagus bliteus Riek for the biological control of the eucalyptus pest Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae) nymphs is high. This research sought to analyze the courtship, male competition, and mating behavior of P. bliteus at the proportions of 1:1 and 2:1 males to female in a Petri dish (5 cm diameter), and to describe the ovary histology of virgin and mated females of this parasitoid. At 1:1, males touch the antennae and thorax-abdomen of females during courtship, but females avoid mate attempts before they are 48 h old. At 2:1, the competition between male parasitoids inhibits mating. The histology of ovaries of virgin and mated P. bliteus females is similar, with two well-defined germarium and vitellarium regions, with oocytes at different developmental stages, including mature ones rich in yolk and with eggshell. A clearer understanding of the reproductive behavior and histology of P. bliteus aids in the use of this parasitoid for the biological control of G. brimblecombei.


Assuntos
Himenópteros/anatomia & histologia , Himenópteros/fisiologia , Comportamento Sexual Animal , Animais , Corte , Feminino , Hemípteros/crescimento & desenvolvimento , Hemípteros/parasitologia , Interações Hospedeiro-Parasita , Controle de Insetos , Masculino , Ninfa/parasitologia , Ovário/anatomia & histologia , Controle Biológico de Vetores
3.
BMC Ecol Evol ; 21(1): 55, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33849454

RESUMO

Why females engage in social polygyny remains an unresolved question in species where the resources provided by males maximize female fitness. In these systems, the ability of males to access several females, as well as the willingness of females to mate with an already mated male, and the benefits of this choice, may be constrained by the socio-ecological factors experienced at the local scale. Here, we used a 19-year dataset from an individual-monitored population of pied flycatchers (Ficedula hypoleuca) to establish local networks of breeding pairs. Then, we examined whether the probability of becoming socially polygynous and of mating with an already mated male (thus becoming a secondary female) is influenced by morphological and sexual traits as proxies of individual quality relative to the neighbours. We also evaluated whether social polygyny is adaptive for females by examining the effect of females' mating status (polygamously-mated vs monogamously-mated) on direct (number of recruits in a given season) and indirect (lifetime number of fledglings produced by these recruits) fitness benefits. The phenotypic quality of individuals, by influencing their breeding asynchrony relative to their neighbours, mediated the probability of being involved in a polygynous event. Individuals in middle-age (2-3 years), with large wings and, in the case of males, with conspicuous sexual traits, started to breed earlier than their neighbours. By breeding locally early, males increased their chances of becoming polygynous, while females reduced their chances of mating with an already mated male. Our results suggest that secondary females may compensate the fitness costs, if any, of sharing a mate, since their number of descendants did not differ from monogamous females. We emphasize the need of accounting for local breeding settings (ecological, social, spatial, and temporal) and the phenotypic composition of neighbours to understand individual mating decisions.


Assuntos
Casamento , Comportamento Sexual Animal , Animais , Pré-Escolar , Feminino , Masculino , Fenótipo , Probabilidade , Reprodução
4.
Nat Commun ; 12(1): 2453, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33907186

RESUMO

Parasitoid wasps inflict widespread death upon the insect world. Hundreds of thousands of parasitoid wasp species kill a vast range of insect species. Insects have evolved defensive responses to the threat of wasps, some cellular and some behavioral. Here we find an unexpected response of adult Drosophila to the presence of certain parasitoid wasps: accelerated mating behavior. Flies exposed to certain wasp species begin mating more quickly. The effect is mediated via changes in the behavior of the female fly and depends on visual perception. The sight of wasps induces the dramatic upregulation in the fly nervous system of a gene that encodes a 41-amino acid micropeptide. Mutational analysis reveals that the gene is essential to the behavioral response of the fly. Our work provides a foundation for further exploration of how the activation of visual circuits by the sight of a wasp alters both sexual behavior and gene expression.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila simulans/genética , Drosophila/genética , Receptores Ionotrópicos de Glutamato/genética , Receptores Odorantes/genética , Comportamento Sexual Animal/fisiologia , Vespas/patogenicidade , Adaptação Fisiológica , Animais , Animais Geneticamente Modificados , Carnivoridade/fisiologia , Drosophila/metabolismo , Drosophila/parasitologia , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Drosophila melanogaster/parasitologia , Drosophila simulans/metabolismo , Drosophila simulans/parasitologia , Feminino , Fertilidade/genética , Regulação da Expressão Gênica , Masculino , Neurônios/citologia , Neurônios/metabolismo , Reconhecimento Visual de Modelos/fisiologia , Receptores Ionotrópicos de Glutamato/deficiência , Receptores Odorantes/deficiência , Vespas/fisiologia , beta-Caroteno 15,15'-Mono-Oxigenase/genética , beta-Caroteno 15,15'-Mono-Oxigenase/metabolismo
5.
Biol Lett ; 17(3): 20200915, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33653095

RESUMO

Intralocus sexual conflict arises when the expression of shared alleles at a single locus generates opposite fitness effects in each sex (i.e. sexually antagonistic alleles), preventing each sex from reaching its sex-specific optimum. Despite its importance to reproductive success, the relative contribution of intralocus sexual conflict to male pre- and post-copulatory success is not well-understood. Here, we used a female-limited X-chromosome (FLX) evolution experiment in Drosophila melanogaster to limit the inheritance of the X-chromosome to the matriline, eliminating possible counter-selection in males and allowing the X-chromosome to accumulate female-benefit alleles. After more than 100 generations of FLX evolution, we studied the effect of the evolved X-chromosome on male attractiveness and sperm competitiveness. We found a non-significant increase in attractiveness and decrease in sperm offence ability in males expressing the evolved X-chromosomes, but a significant increase in their ability to avoid displacement by other males' sperm. This is consistent with a trade-off between these traits, perhaps mediated by differences in body size, causing a small net reduction in overall male fitness in the FLX lines. These results indicate that the X-chromosome in D. melanogaster is subject to selection via intralocus sexual conflict in males.


Assuntos
Drosophila melanogaster , Caracteres Sexuais , Animais , Evolução Biológica , Tamanho Corporal , Cromossomos , Drosophila melanogaster/genética , Feminino , Masculino , Reprodução , Seleção Genética , Comportamento Sexual Animal
6.
Science ; 371(6533): 976-977, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33674475
7.
Nat Commun ; 12(1): 1775, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33741978

RESUMO

Human society is cooperative and characterized by spontaneous prosociality. Comparative studies on endotherm vertebrates suggest that social interdependence causes the evolution of proactive prosociality. To test the generality of this hypothesis, we modify a prosocial choice task for application to the convict cichlid, Amatitlania nigrofasciata, a monogamous fish with biparental care and a strong pair bond. We also affirm that male subjects learn to favor prosocial choices when their mates are the recipients in a neighboring tank. When the neighboring tank is empty, males choose randomly. Furthermore, in the absence of their mates, males behave prosocially toward a stranger female. However, if the mate of the subjects is also visible in the third tank, or if a male is a potential recipient, then subjects make antisocial choices. To conclude, fish may show both spontaneous prosocial and antisocial behaviors according to their social relationships with conspecifics and the overall social context.


Assuntos
Comportamento de Escolha/fisiologia , Ciclídeos/fisiologia , Comportamento Sexual Animal/fisiologia , Comportamento Social , Animais , Feminino , Humanos , Masculino , Ligação do Par , Reprodução/fisiologia
8.
J Vis Exp ; (169)2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33749672

RESUMO

Current risk assessment strategies for honey bees rely heavily upon laboratory tests performed on adult or immature worker bees, but these methods may not accurately capture the effects of agrochemical exposure on honey bee queens. As the sole producer of fertilized eggs inside a honeybee colony, the queen is arguably the most important single member of a functioning colony unit. Therefore, understanding how agrochemicals affect queen health and productivity should be considered a critical aspect of pesticide risk assessment. Here, an adapted method is presented to expose honey bee queens and worker queen attendants to agrochemical stressors administered through a worker diet, followed by tracking egg production in the laboratory and assessing first instar eclosion using a specialized cage, referred to as a Queen Monitoring Cage. To illustrate the method's intended use, results of an experiment in which worker queen attendants were fed diet containing sublethal doses of imidacloprid and effects on queens were monitored are described.


Assuntos
Agroquímicos/toxicidade , Abelhas/efeitos dos fármacos , Abelhas/fisiologia , Hierarquia Social , Medição de Risco , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Abelhas/embriologia , Comportamento Alimentar/efeitos dos fármacos , Feminino , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Óvulo/efeitos dos fármacos , Reprodução/efeitos dos fármacos
9.
Nat Commun ; 12(1): 1350, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649298

RESUMO

Sexual selection drives rapid phenotypic diversification of mating traits. However, we know little about the causative genes underlying divergence in sexually selected traits. Here, we investigate the genetic basis of male mating trait diversification in the medaka fishes (genus Oryzias) from Sulawesi, Indonesia. Using linkage mapping, transcriptome analysis, and genome editing, we identify csf1 as a causative gene for red pectoral fins that are unique to male Oryzias woworae. A cis-regulatory mutation enables androgen-induced expression of csf1 in male fins. csf1-knockout males have reduced red coloration and require longer for mating, suggesting that coloration can contribute to male reproductive success. Contrary to expectations, non-red males are more attractive to a predatory fish than are red males. Our results demonstrate that integrating genomics with genome editing enables us to identify causative genes underlying sexually selected traits and provides a new avenue for testing theories of sexual selection.


Assuntos
Edição de Genes , Aptidão Genética , Oryzias/genética , Caracteres Sexuais , Nadadeiras de Animais/anatomia & histologia , Animais , Feminino , Regulação da Expressão Gênica , Estudos de Associação Genética , Indonésia , Fator Estimulador de Colônias de Macrófagos/genética , Masculino , Mutação/genética , Filogenia , Pigmentação/genética , Comportamento Predatório , Locos de Características Quantitativas/genética , Comportamento Sexual Animal
10.
J Econ Entomol ; 114(1): 142-151, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33558906

RESUMO

Survival and mating success are traits of quality in mass-reared sterile males. Thus, studying the trade-offs between these traits may help to improve process in the sterile insect technique (SIT). Here, we tested the hypothesis that modifying individual metabolism, especially of energetic reserves, may reduce the negative impact of an early reproduction on the survival of Anastrepha ludens flies. Appling metformin (a drug used to treat type II diabetes) that improves insects' survival, through dietary restriction mimicry, and methoprene (a juvenile hormone analogue) that accelerates the age to reproduction in insects, we explore the dynamic of this trade-off. We fed A. ludens flies with metformin, methoprene, or a mixture of metformin-methoprene for five consecutive days. We determined the effect of these treatments on the fecundity and fertility (number of eggs and percentage of hatching) of females, on sexual maturation and mating success of males, and on the survival of both sexes. The results showed that the acceleration in sexual maturation by the action of methoprene significantly reduced survival in both sexes of two different fly strains. However, adding metformin to the diet buffered this negative effect, without reducing the mating propensity compared with the males treated only with methoprene. The response to metformin was sex-specific since females responded to high doses of the substance, whereas males responded better to low doses. These results suggest that trade-offs between survival and reproduction do not necessarily depend on energy reserves but they are intrinsically related to metabolic regulation and hormonal control.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Tephritidae , Animais , Feminino , Longevidade , Masculino , Metoprene , Reprodução , Comportamento Sexual Animal
11.
BMC Ecol Evol ; 21(1): 23, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33573597

RESUMO

INTRODUCTION: Male genitalia are thought to ensure transfer of sperm through direct physical contact with female during copulation. However, little attention has been given to their pre-copulatory role with respect to sexual selection and sexual conflict. Males of the fruitfly Drosophila pachea have a pair of asymmetric external genital lobes, which are primary sexual structures and stabilize the copulatory complex of female and male genitalia. We wondered if genital lobes in D. pachea may have a role before or at the onset of copulation, before genitalia contacts are made. RESULTS: We tested this hypothesis with a D. pachea stock where males have variable lobe lengths. In 92 mate competition trials with a single female and two males, females preferentially engaged into a first copulation with males that had a longer left lobe and that displayed increased courtship vigor. In 53 additional trials with both males having partially amputated left lobes of different lengths, we observed a weaker and non-significant effect of left lobe length on copulation success. Courtship durations significantly increased with female age and when two males courted the female simultaneously, compared to trials with only one courting male. In addition, lobe length did not affect sperm transfer once copulation was established. CONCLUSION: Left lobe length affects the chance of a male to engage into copulation. The morphology of this primary sexual trait may affect reproductive success by mediating courtship signals or by facilitating the establishment of genital contacts at the onset of copulation.


Assuntos
Drosophila , Comportamento Sexual Animal , Animais , Copulação , Feminino , Genitália Masculina , Masculino , Reprodução
12.
Animal ; 15(2): 100114, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33573958

RESUMO

In confined management systems, well-nourished bucks rendered sexually active by exposure to long days are efficient in fertilizing out-of-season goats. However, underfeeding is common in semi-extensive management systems and may reduce the reproductive efficiency of bucks. The objective of the present study was to determine whether nutritional supplementation improved the sexual activity of bucks submitted to long days in semi-extensive management systems and their ability to stimulate the reproduction of goats in semi-extensive or confined conditions. In experiment 1, three groups of bucks were placed in different flocks and grazed daily with females for 7 h. Each day after grazing, males were separated from females and moved into open pens. One group did not receive any treatment (control group; n = 6). Two other groups were submitted to artificially long days from 15 November to 15 January. From 16 January, one group did not receive nutritional supplementation (long-day group; n = 5), whereas bucks from the other group each received 600 g of a commercial concentrate (long-day+supplementation group; n = 5). The fourth group was kept in confined conditions, exposed to long days and fed alfalfa hay (long-day confined group; n = 6). On 26 March, anovulatory goats from other flocks were assigned to four groups (n = 27 each) and confined separately in open pens. Three bucks of each group were housed with the females. Pregnancy rates were greater in the goats housed with the long-day group than those housed with the control group (P < 0.01). However, pregnancy rates did not differ between the long-day confined group (89%) and long-day+supplementation group (70%; P = 0.09), but these rates were greater than those from the long-day (37%) and control groups (0%; P < 0.05). In experiment 2, two groups of males (n = 3 each) were incorporated into two flocks under semi-extensive management and grazed daily with females for 7 h. One group of males did not receive any treatment (control group). The other group was submitted to long days and nutritional supplementation as in experiment 1 (long-day+supplementation group). Males remained with females during the whole study. The pregnancy rate was greater in the goats joined by males of the long-day+supplementation group (78%) than in those from the control group (0%; P < 0.001). We conclude that long days and nutritional supplementation improve the ability of bucks kept in semi-extensive management to stimulate reproduction of out-of-season goats in confined or semi-extensive management systems.


Assuntos
Cabras , Comportamento Sexual Animal , Animais , Suplementos Nutricionais , Feminino , Masculino , Gravidez , Reprodução , Estações do Ano
13.
Zoolog Sci ; 38(1): 45-50, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33639717

RESUMO

In medaka fishes, the family Adrianichthyidae, tropical species are known to be sexually more dimorphic than temperate species. If this reflects that tropical species are exposed to stronger sexual-selection pressures than temperate species, mating behaviors may also differ between tropical and temperate species. Our mating experiments revealed that males of Oryzias woworae, a tropical species of the family, perform "chasing" another male more frequently than males of O. sakaizumii, a temperate congener, and that male-male "combats" of O. woworae tended to be followed by chasing compared with combats of O. sakaizumii males, indicating that O. woworae males are more aggressive in male-male interactions than O. sakaizumii males. Males of O. woworae also performed "approaching" a female and "mating dance" more frequently than O. sakaizumii males, indicating that O. woworae males are also more active in courting females. Males of O. sakaizumii often omitted "mating dance" in their mating sequences, supporting this view. Moreover, O. woworae females tended to reject male "wrapping", an attempt for fertilization, more frequently than O. sakaizumii females, suggesting that O. woworae females are choosier in mating than O. sakaizumii females. These findings are concordant with the view that O. woworae is exposed to stronger sexual-selection pressures than O. sakaizumii.


Assuntos
Agressão , Oryzias/fisiologia , Comportamento Sexual Animal , Animais , Feminino , Masculino , Especificidade da Espécie
14.
J Sex Med ; 18(2): 240-255, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33419705

RESUMO

BACKGROUND: Preclinical studies that have examined the effects of androgen deprivation therapies (ADTs) on sexual outcomes have either relied on a surgical castration model of ADTs or have largely focused on consummatory sexual behaviors. AIM: The aim of this study was to examine the effects of a single administration of the gonadotropin-releasing hormone receptor antagonist, degarelix, on sexual incentive motivation (SIM), sexual reward, consummatory sexual behaviors, anxiety-like behavior, and androgen receptor signaling in male rats, and to determine if sexual stimulation attenuates the effects of degarelix on SIM. METHODS: Male rats were treated with degarelix, or vehicle, and half of the rats in each condition were briefly exposed to a sexually receptive female immediately before SIM trials (experiment 1). Rats treated with degarelix or vehicle were also given a sex-conditioned place preference test (experiment 2A), weekly mating tests (experiment 2B), and an elevated zero maze test (experiment 3). Androgen-sensitive tissues were excised upon completion of testing. OUTCOMES: SIM was indicated by the percentage of time spent near a sexually receptive female on the SIM tests. The percentage of time spent in the chamber of a conditioned place preference maze associated with sexual experience was indicative of sexual reward. The percentage of trials in which a mount, intromission, and ejaculation occurred was indicative of copulatory ability. Sexual performance was characterized by the average latencies to first exhibit these behaviors, as well as the average frequency of these behaviors. Anxiety-like behavior was indicated by the percentage of time in the open zones of an elevated zero maze. Relative weights of the seminal vesicles and bulbourethral glands were used to quantify androgen activity. RESULTS: Rats treated with degarelix exhibited lower levels of SIM. In rats treated with degarelix, contact with a female immediately before SIM testing increased activity, but not SIM. Treatment with degarelix reduced the rewarding aspects of sexual behavior, as well as most aspects of copulatory ability and sexual performance. Degarelix treatment reduced androgen signaling, but did not impact anxiety-like behavior. CLINICAL IMPLICATIONS: The behavioral side effects associated with the use of degarelix may be restricted to sexual behaviors. STRENGTHS & LIMITATIONS: Strengths include the objective measurement of sexual behaviors. The study is limited in that only one ADT was examined. CONCLUSION: These findings serve as an extension of previous preclinical studies as they indicate that gonadotropin-releasing hormone receptor antagonism in male rats also attenuates sexual motivation and sexual reward, in addition to copulatory ability and sexual performance. Hawley WR, Kapp LE, Green PA, et al. Sexual Motivation and Reward in Male Rats are Attenuated by the Gonadotropin-Releasing Hormone Receptor Antagonist Degarelix. J Sex Med 2021;18:240-255.


Assuntos
Motivação , Neoplasias da Próstata , Antagonistas de Androgênios , Animais , Hormônio Liberador de Gonadotropina , Humanos , Masculino , Oligopeptídeos , Ratos , Receptores LHRH , Recompensa , Comportamento Sexual Animal
15.
Proc Natl Acad Sci U S A ; 118(1)2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33443193

RESUMO

Drosophila melanogaster females experience a large shift in energy homeostasis after mating to compensate for nutrient investment in egg production. To cope with this change in metabolism, mated females undergo widespread physiological and behavioral changes, including increased food intake and altered digestive processes. The mechanisms by which the female digestive system responds to mating remain poorly characterized. Here, we demonstrate that the seminal fluid protein Sex Peptide (SP) is a key modulator of female post-mating midgut growth and gene expression. SP is both necessary and sufficient to trigger post-mating midgut growth in females under normal nutrient conditions, and likely acting via its receptor, Sex Peptide Receptor (SPR). Moreover, SP is responsible for almost the totality of midgut transcriptomic changes following mating, including up-regulation of protein and lipid metabolism genes and down-regulation of carbohydrate metabolism genes. These changes in metabolism may help supply the female with the nutrients required to sustain egg production. Thus, we report a role for SP in altering female physiology to enhance reproductive output: Namely, SP triggers the switch from virgin to mated midgut state.


Assuntos
Sistema Digestório/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Fertilidade/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Receptores de Peptídeos/metabolismo , Reprodução/fisiologia , Transcriptoma/genética , Animais , Copulação , Sistema Digestório/anatomia & histologia , Sistema Digestório/crescimento & desenvolvimento , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Feminino , Fertilidade/genética , Ontologia Genética , Intestinos/anatomia & histologia , Intestinos/crescimento & desenvolvimento , Intestinos/fisiologia , Masculino , Receptores de Peptídeos/genética , Reprodução/genética , Sêmen/metabolismo , Comportamento Sexual Animal/fisiologia , Transcriptoma/fisiologia
16.
Proc Biol Sci ; 288(1942): 20202679, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33402074

RESUMO

Like many animals, adult male chimpanzees often compete for a limited number of mates. They fight other males as they strive for status that confers reproductive benefits and use aggression to coerce females to mate with them. Nevertheless, small-bodied, socially immature adolescent male chimpanzees, who cannot compete with older males for status nor intimidate females, father offspring. We investigated how they do so through a study of adolescent and young adult males at Ngogo in Kibale National Park, Uganda. Adolescent males mated with nulliparous females and reproduced primarily with these first-time mothers, who are not preferred as mating partners by older males. Two other factors, affiliation and aggression, also influenced mating success. Specifically, the strength of affiliative bonds that males formed with females and the amount of aggression males directed toward females predicted male mating success. The effect of male aggression toward females on mating success increased as males aged, especially when they directed it toward females with whom they shared affiliative bonds. These results mirror sexual coercion in humans, which occurs most often between males and females involved in close, affiliative relationships.


Assuntos
Coerção , Pan troglodytes , Adolescente , Agressão , Animais , Feminino , Humanos , Masculino , Reprodução , Comportamento Sexual Animal , Uganda
17.
Biol Lett ; 17(1): 20200811, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33465328

RESUMO

Sexual conflict can generate coercive traits in males that enhance mating success at the expense of female fitness. Pre-copulatory sexual cannibalism-where females consume males without mating-typically favours cautious rather than coercive mating tactics, and few examples of the latter are known. Here, we show that males of the highly cannibalistic springbok mantis, Miomantis caffra, wrestle females during pre-mating interactions. We find that most initial contacts between males and females involve a violent struggle whereby each sex tries be the first to grasp hold of the other with their raptorial forelegs. When females win the struggle, they always cannibalize males. However, when males grasp females first, they dramatically increase the chance of mating. We also find striking evidence that, on some occasions, males wound females with their fore-tibial claws during struggles, resulting in haemolymph loss and scar tissue formation. Taken together, our results show how males can overcome the threat of cannibalism by coercively wrestling females. We argue that pre-copulatory injury in this species is likely to be a negative pleiotropic side-effect of coercive mating behaviour and foraging morphology.


Assuntos
Canibalismo , Mantódeos , Animais , Coerção , Copulação , Feminino , Masculino , Comportamento Sexual Animal
18.
PLoS One ; 16(1): e0244648, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33417615

RESUMO

Honey bee (Apis mellifera) queens have a remarkable organ, the spermatheca, which successfully stores sperm for years after a virgin queen mates. This study uniquely characterized and quantified the transcriptomes of the spermathecae from mated and virgin honey bee queens via RNA sequencing to identify differences in mRNA levels based on a queen's mating status. The transcriptome of drone semen was analyzed for comparison. Samples from three individual bees were independently analyzed for mated queen spermathecae and virgin queen spermathecae, and three pools of semen from ten drones each were collected from three separate colonies. In total, the expression of 11,233 genes was identified in mated queen spermathecae, 10,521 in virgin queen spermathecae, and 10,407 in drone semen. Using a cutoff log2 fold-change value of 2.0, we identified 212 differentially expressed genes between mated and virgin spermathecal queen tissues: 129 (1.4% of total) were up-regulated and 83 (0.9% of total) were down-regulated in mated queen spermathecae. Three genes in mated queen spermathecae, three genes in virgin queen spermathecae and four genes in drone semen that were more highly expressed in those tissues from the RNA sequencing data were further validated by real time quantitative PCR. Among others, expression of Kielin/chordin-like and Trehalase mRNAs was highest in the spermathecae of mated queens compared to virgin queen spermathecae and drone semen. Expression of the mRNA encoding Alpha glucosidase 2 was higher in the spermathecae of virgin queens. Finally, expression of Facilitated trehalose transporter 1 mRNA was greatest in drone semen. This is the first characterization of gene expression in the spermathecae of honey bee queens revealing the alterations in mRNA levels within them after mating. Future studies will extend to other reproductive tissues with the purpose of relating levels of specific mRNAs to the functional competence of honey bee queens and the colonies they head.


Assuntos
Abelhas/genética , Transcriptoma , Animais , Abelhas/fisiologia , Feminino , Genes de Insetos , Inseminação , Masculino , Reprodução , Sêmen/fisiologia , Comportamento Sexual Animal , Espermatozoides/fisiologia
19.
Proc Biol Sci ; 288(1943): 20202371, 2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33499789

RESUMO

In socially monogamous species, pair-bonded males often continue to provide care to all offspring in their nests despite some degree of paternity loss due to female extra-pair copulation. Previous theoretical models suggested that females can use their within-pair offspring as 'hostages' to blackmail their social mates, so that they continue to provide care to the brood at low levels of cuckoldry. These models, however, rely on the assumption of sufficiently accurate male detection of cuckoldry and the reduction of parental effort in case of suspicion. Therefore, they cannot explain the abundant cases where cuckolded males continue to provide extensive care to the brood. Here we use an analytical population genetics model and an individual-based simulation model to explore the coevolution of female fidelity and male help in populations with two genetically determined alternative reproductive tactics (ARTs): sneakers that achieve paternity solely via extra-pair copulations and bourgeois that form a mating pair and spend some efforts in brood care. We show that when the efficiency of mate guarding is intermediate, the bourgeois males can evolve to 'specialize' in providing care by spending more than 90% of time in helping their females while guarding them as much as possible, despite frequent cuckoldry by the sneakers. We also show that when sneakers have tactic-specific adaptations and thus are more competitive than the bourgeois in gaining extra-pair fertilizations, the frequency of sneakers and the degrees of female fidelity and male help can fluctuate in evolutionary cycles. Our theoretical predictions highlight the need for further empirical tests in species with ARTs.


Assuntos
Reprodução , Comportamento Sexual Animal , Adaptação Fisiológica , Animais , Evolução Biológica , Copulação , Feminino , Masculino
20.
Pest Manag Sci ; 77(5): 2522-2529, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33460523

RESUMO

BACKGROUND: The sterile insect technique (SIT) is used in Australia to contain and eradicate outbreaks of Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) in fruit-fly-free regions, and to manage populations in some endemic regions. To assess the likely impact of SIT on wild B. tryoni populations it is important to assess the colocation and synchrony of male calling between sterile and wild flies. We observed the location and timing of calling behaviours of marked mass-reared (fertile and sterile) and wild B. tryoni males in walk-in field cages. RESULTS: We found that wild males called further from the canopy centre than mass-reared (fertile or sterile) males. Mass-reared (fertile or sterile) males called earlier in the evening than wild males and, consequently, mass-reared males called when temperature and light intensity were higher than when wild males called. CONCLUSION: Male calling is a prerequisite to mating among dacine fruit flies. Therefore, our observations of spatio-temporal divergence in male calling behaviour may lead to assortative mating between mass-reared and wild B. tryoni in SIT applications. The importance of these spatio-temporal differences warrants further inquiry, with particular focus on how environmental conditions modify calling behaviour and avenues to ameliorate differences between sterile and wild flies. © 2021 Society of Chemical Industry.


Assuntos
Tephritidae , Animais , Austrália , Masculino , Comportamento Sexual Animal
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