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1.
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
2.
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
3.
Gene ; 776: 145446, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33484761

RESUMO

Bumblebees are important pollinators that have evolved between solitary and advanced eusocial insects. Compared with advanced honeybees, workers of social bumblebee species are prone to laying eggs during the competition phase, which leads to the end of the colony. Therefore, worker reproductive behavior has become a popular research topic for exploring various biological phenomena. Here, we demonstrate a novel reproduction-related function of an immune response protein-encoding gene (Immune Responsive Protein 30, IRP30) in Bombus terrestris by employing RNA interference (RNAi) and a transgenic Drosophila melanogaster system. The results show that worker egg-laying was significantly affected by IRP30 expression levels (P < 0.01). Compared with those in the dsGFP-treated groups, the first egg-laying time was delayed by 3.7 d and the egg number was decreased by 41% in the dsIRP30-treated group. In addition, the average size of the largest oocyte and the relative mRNA expression levels of Vg (vitellogenin) were significantly reduced in the dsIRP30-treated group (P < 0.05). Cellular localization by immunofluorescence demonstrated that IRP30 has important functions in the germ cells of workers' ovarioles. Overexpression of IRP30 was confirmed to increase the reproductive capability of the transgenic D. melanogaster. In conclusion, IRP30 regulates worker egg-laying by affecting the expression of Vg, the size of the ovary and the formation of the oocyte. These findings provide essential information for understanding the mechanisms underlying worker reproductive regulation.


Assuntos
Abelhas/genética , Abelhas/metabolismo , Reprodução/genética , Animais , Animais Geneticamente Modificados/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Expressão Gênica/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Ovário/metabolismo , Oviposição , Óvulo/metabolismo , Polinização , Reprodução/fisiologia , Comportamento Sexual Animal/fisiologia , Vitelogeninas/genética
4.
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
5.
Proc Biol Sci ; 287(1941): 20202229, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33323074

RESUMO

Intense sexual selection in the form of mate choice can facilitate the evolution of different alternative reproductive strategies, which can be condition-dependent. Tree cricket males produce long-distance acoustic signals which are used by conspecific females for mate localization and mate choice. Our study shows that baffling, an acoustic call amplification strategy employed by male tree crickets using self-made tools, is a classic example of a condition-dependent alternative strategy. We show that though most males can baffle, less preferred males, such as smaller and lower-amplitude callers, predominantly use this alternative strategy. Baffling allows these males to increase their call amplitude and advertisement range, which attracts a higher number of females. Baffling also gives these males a mating benefit because females mate for longer durations with them. Our results suggest that the advantage of baffling in terms of gain in the number of sperm cells transferred while mating is primarily limited to less preferred males, thus maintaining the polymorphism of calling strategies in the population. We summarize that baffling is a condition-dependent strategy used by less preferred tree cricket males to obtain mating benefits.


Assuntos
Gryllidae/fisiologia , Comportamento Sexual Animal/fisiologia , Acústica , Animais , Feminino , Masculino , Preferência de Acasalamento Animal/fisiologia , Árvores
6.
Sci Rep ; 10(1): 22328, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33339880

RESUMO

In the cricket Gryllus bimaculatus, flying occurs soon after the last imaginal molt and precedes the mating behavior in natural conditions. Here, we tested the hypothesis that flying may improve subsequent behavioral performance in a novel environment in female crickets. We developed a behavioral set-up to test female cricket responsiveness to male calling song as well as their ability to locate and find the source of the song. The male song was produced by a loudspeaker hidden behind the fabric wall of a spacious square arena. Forced flight prior to the test promoted female sexual searching behavior in the novel environment. After the flight, more females reached the hidden source zone, spent more time near the source and finally more of them climbed over the wall section immediately in front of the hidden loudspeaker. At the same time, their behavior in the arena did not differ from the control group when the calling song was not delivered, suggesting that flight exerts its behavioral effects by influencing sexual motivation. Our results support the suggestion that preceding intense locomotion facilitates sexual searching behavior of females in a novel environment.


Assuntos
Gryllidae/fisiologia , Comportamento Sexual Animal/fisiologia , Vocalização Animal/fisiologia , Comunicação Animal , Animais , Percepção Auditiva , Feminino , Interneurônios/fisiologia , Masculino
7.
PLoS One ; 15(12): e0244561, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33378375

RESUMO

The variation in temperament among animals has consequences for evolution and ecology. One of the primary effects of consistent behavioral differences is on reproduction. In chelonians some authors have focused on the study of temperament using different methods. In our research our first aim was i) establish a methodology to determine the degree of boldness among individuals Rhinoclemmys areolata. Our second aim was to ii) determine the role boldness plays during reproduction, with emphasis on courtship and copulation, considering a) the interactions between males and females, and b) competition between males. We used 16 sexually mature individuals of each sex. Males were observed in four different situations and 17 behavioral traits were recorded. We selected 12 traits that allowed us distinguish between the bolder and the shier individuals and found that five behavioral traits were specific for bolder individuals and five others for shier individuals. In a second step, we observed a male in presence of a female and recorded courtship behaviors and breeding attempts. Bolder individuals did not display courtship behaviors and just attempted to copulate. Shier individuals displayed courtship behaviors and copulation attempts were rarely observed. Finally, in the simulations that compared two males in the presence of a female we noticed that bolder individuals displayed courtship behaviors while the shier ones simply ignored the female. Our results first allowed us to determine which methodology is the best to determine temperament in turtles. Secondly, temperament seems to be an important factor in modulating interaction between males and females. Bolder individuals have an advantage during competition and display courtship behaviours only if other males are present. Shier males displayed courtship behaviors and only try to copulate when no competitors were present. These two different temperament-dependant strategies are discussed in terms of ecology, evolution and management.


Assuntos
Comportamento Sexual Animal/fisiologia , Temperamento/fisiologia , Tartarugas/fisiologia , Animais , Cruzamento , Copulação , Corte , Feminino , Masculino
8.
Sci Rep ; 10(1): 21932, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33318613

RESUMO

The past 2 decades have seen fruit flies being widely adopted for research on social behavior and aggression. This fruitful research, however, has not been well tied to fruit flies' natural history. To address this knowledge gap, I conducted a field study. My goal was to inform future research conducted in artificial surroundings, and to inspire new investigations that can rely more heavily on fruit flies' actual natural behavior. My two main novel findings were first, that flies in the field showed significant sociability, as they formed social groups rather than dispersed randomly among fruits of similar quality. Second, males showed fair levels of aggression towards each other as indicated by a lunging rate of 17 per hour, and lower rates of wing threat and boxing. Courtship was the most prominent activity on fruits, with females rejecting almost all males' advances. This resulted in an estimated mating rate of 0.6 per female per day. Flies showed a striking peak of activity early in the mornings, even at cold temperatures, followed by inactivity for much of the day and night. Flies, however, handled well high temperatures approaching 40 °C by hiding away from fruit and concentrating activity in the cooler, early mornings. My field work highlights a few promising lines of future research informed by fruit flies' natural history. Most importantly, we do not understand the intriguing dynamics that generate significant sociability despite frequent aggressive interactions on fruits. Males' responses to female rejection signals varied widely, perhaps because the signals differed in information content perceived by flies but not humans. Finally, flies tolerated cold early mornings perhaps owing to fitness benefits associated with increased mating and feeding opportunities at this time. Flies were adept at handling very high temperatures under the natural daily temperature fluctuations and availability of shelters, and this can inform more realistic research on the effects of global warming on animals in their natural settings.


Assuntos
Comportamento Sexual Animal/fisiologia , Comportamento Social , Animais , Drosophila melanogaster , Feminino , Masculino
9.
PLoS One ; 15(9): e0232306, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986707

RESUMO

Tsetse eradication continues to be a top priority for African governments including that of Senegal, which embarked on a project to eliminate Glossina palpalis gambiensis from the Niayes area, following an area-wide integrated pest management approach with an SIT component. A successful SIT programme requires competitive sterile males of high biological quality. This may be hampered by handling processes including irradiation and the release mechanisms, necessitating continued improvement of these processes, to maintain the quality of flies. A new prototype of an automated chilled adult release system (Bruno Spreader Innovation, (BSI™)) for tsetse flies was tested for its accuracy (in counting) and release rate consistency. Also, its impact on the quality of the released sterile males was evaluated on performance indicators, including flight propensity, mating competitiveness, premating and mating duration, insemination rate of mated females and survival of male flies. The BSITM release system accurately counted and homogenously released flies at the lowest motor speed set (0.6 rpm), at a consistent rate of 60±9.58 males/min. Also, the release process, chilling (6 ± 1°C) and passing of flies through the machine) had no significant negative impact on the male flight propensity, mating competitiveness, premating and mating durations and the insemination rates. Only the survival of flies was negatively affected whether under feeding or starvation. The positive results of this study show that the BSI™ release system is promising for use in future tsetse SIT programmes. However, the negative impact of the release process on survival of flies needs to be addressed in future studies and results of this study confirmed under operational field conditions in West Africa.


Assuntos
Temperatura Baixa/efeitos adversos , Infertilidade Masculina/veterinária , Controle Biológico de Vetores/métodos , Tripanossomíase Africana/prevenção & controle , Moscas Tsé-Tsé/fisiologia , Animais , Vetores de Doenças , Feminino , Voo Animal/fisiologia , Humanos , Infertilidade Masculina/etiologia , Gado/parasitologia , Masculino , Controle Biológico de Vetores/instrumentação , Senegal , Comportamento Sexual Animal/fisiologia , Trypanosoma/patogenicidade , Tripanossomíase Africana/parasitologia , Tripanossomíase Africana/veterinária , Moscas Tsé-Tsé/parasitologia
10.
Proc Natl Acad Sci U S A ; 117(40): 24920-24928, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32958636

RESUMO

Australian funnel-web spiders are infamous for causing human fatalities, which are induced by venom peptides known as δ-hexatoxins (δ-HXTXs). Humans and other primates did not feature in the prey or predator spectrum during evolution of these spiders, and consequently the primate lethality of δ-HXTXs remains enigmatic. Funnel-web envenomations are mostly inflicted by male spiders that wander from their burrow in search of females during the mating season, which suggests a role for δ-HXTXs in self-defense since male spiders rarely feed during this period. Although 35 species of Australian funnel-web spiders have been described, only nine δ-HXTXs from four species have been characterized, resulting in a lack of understanding of the ecological roles and molecular evolution of δ-HXTXs. Here, by profiling venom-gland transcriptomes of 10 funnel-web species, we report 22 δ-HXTXs. Phylogenetic and evolutionary assessments reveal a remarkable sequence conservation of δ-HXTXs despite their deep evolutionary origin within funnel-web spiders, consistent with a defensive role. We demonstrate that δ-HXTX-Ar1a, the lethal toxin from the Sydney funnel-web spider Atrax robustus, induces pain in mice by inhibiting inactivation of voltage-gated sodium (NaV) channels involved in nociceptive signaling. δ-HXTX-Ar1a also inhibited inactivation of cockroach NaV channels and was insecticidal to sheep blowflies. Considering their algogenic effects in mice, potent insecticidal effects, and high levels of sequence conservation, we propose that the δ-HXTXs were repurposed from an initial insecticidal predatory function to a role in defending against nonhuman vertebrate predators by male spiders, with their lethal effects on humans being an unfortunate evolutionary coincidence.


Assuntos
Evolução Molecular , Neurotoxinas/genética , Poliaminas/química , Aranhas/genética , Sequência de Aminoácidos/genética , Animais , Austrália , Sequência Conservada/genética , Feminino , Humanos , Masculino , Camundongos , Neurotoxinas/química , Neurotoxinas/metabolismo , Peptídeos/genética , Filogenia , Poliaminas/metabolismo , Comportamento Sexual Animal/fisiologia , Venenos de Aranha/genética , Aranhas/patogenicidade , Transcriptoma/genética , Vertebrados/genética , Vertebrados/fisiologia
11.
Proc Biol Sci ; 287(1934): 20201377, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32900311

RESUMO

Ever since Darwin's discovery of natural selection, we expect traits to evolve to increase organisms' fitness. As a result, we can use optimization models to make a priori predictions of phenotypic variation, even when selection is frequency-dependent. A notable example is the prediction of female-biased sex ratios resulting from local mate competition (LMC) and inbreeding. LMC models incorporate the effects of LMC and inbreeding. Fig wasp sex ratio adjustments fit LMC predictions well. However, the appropriateness of LMC models to fig wasps has been questioned, and the role that a coincidental by-product plays in creating the apparent fit has been clearly illustrated. Here, we show that the sex ratio adjustments of a fig wasp are the result of a dual mechanism. It consists of a standard facultative LMC response favoured by natural selection, as well as a mechanism that may be the result of selection, but that could also be a coincidental by-product. If it is a by-product, the fitness increase is coincidental and natural selection's role was limited to fine-tuning it for higher fitness returns. We further document a case of an apparent fitness-reducing sex ratio adjustment. We conclude that the use of the adaptationist approach demands that our understanding of traits must be remodelled continually to rectify spurious assumptions.


Assuntos
Seleção Genética , Comportamento Sexual Animal/fisiologia , Vespas/fisiologia , Animais , Feminino , Masculino , Razão de Masculinidade
12.
Proc Biol Sci ; 287(1934): 20201023, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32900314

RESUMO

Within cooperatively breeding societies, individuals adjust cooperative contributions to maximize indirect fitness and minimize direct fitness costs. Yet, little is known about the physiological costs of cooperation, which may be detrimental to direct fitness. Oxidative stress, the imbalance between reactive oxygen species (by-products of energy production) and antioxidant protection, may represent such a cost when cooperative behaviours are energetically demanding. Oxidative stress can lead to the accumulation of cellular damage, compromising survival and reproduction, thus mediating the trade-off between these competing life-history traits. Here, we experimentally increased energetically demanding cooperative contributions in captive Damaraland mole-rats (Fukomys damarensis). We quantified oxidative stress-related effects of increased cooperation on somatic and germline tissues, and the trade-off between them. Increased cooperative contributions induced oxidative stress in females and males, without increasing somatic damage. Males accumulated oxidative damage in their germline despite an increase in antioxidant defences. Finally, oxidative damage accumulation became biased towards the germline, while antioxidant protection remained biased towards the soma, suggesting that males favour the maintenance of somatic tissues (i.e. survival over reproduction). Our results show that heightened cooperative contributions can ultimately affect direct fitness through oxidative stress costs, which may represent a key selective pressure for the evolution of cooperation.


Assuntos
Comportamento Cooperativo , Ratos-Toupeira/fisiologia , Estresse Oxidativo , Comportamento Sexual Animal/fisiologia , Animais , Cruzamento , Feminino , Masculino
13.
PLoS One ; 15(8): e0236660, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785239

RESUMO

Squamate reptiles (snakes and lizards) rely on chemical cues from conspecifics to search the environment for potential mates. How such cues are used by invasive species to facilitate reproduction, especially seasonally, is a key question that can inform management practices. The Argentine black and white tegu (Salvator merianae) is an invasive reptile species in south Florida threatening native fauna in biodiverse regions such as Everglades National Park. While some information exists on the reproductive ecology of this species in its native range in South America, the chemical ecology of S. merianae is unclear especially in its invasive range. By testing both male (n = 7) and female (n = 7) tegus in a Y-maze apparatus, we assessed if either sex follows chemical trails left by conspecifics and if behaviors were sex- or season-specific. We conducted three types of trials where conspecifics created odor trails: Male-only (male scent only in base and one arm of Y), Female-only, and Male vs. female. Males did not preferentially follow scent trails from either sex, but they did differentially investigate conspecific scent from both sexes. Seasonally, males showed increased rates of chemosensory sampling (rates of tongue-flicking) during the spring (breeding season; March-May) compared to fall (non-breeding season; September-November). Males also had reduced turning and pausing behavior while trailing in the spring. Female tegus exhibited stronger conspecific trailing abilities than males, following both male and female scent trails, and they explored the maze less before making an arm choice. Females also investigated the scent trails intensely compared to males (more passes in scented arms, more time with scent trails). Our results demonstrate for the first time that females of an invasive reptile species can follow conspecific scent trails. Given the strong female responses to odor, sex-specific targeting of tegus via application of a conspecific chemical cue in traps could enhance removal rates of females during the breeding season.


Assuntos
Lagartos/fisiologia , Casamento , Comportamento Sexual Animal/fisiologia , Serpentes/fisiologia , Animais , Ecologia , Feminino , Florida , Humanos , Espécies Introduzidas , Masculino , Odorantes/análise , Reprodução/fisiologia , América do Sul
14.
Nat Commun ; 11(1): 3962, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32770059

RESUMO

Social context can dampen or amplify the perception of touch, and touch in turn conveys nuanced social information. However, the neural mechanism behind social regulation of mechanosensation is largely elusive. Here we report that fruit flies exhibit a strong defensive response to mechanical stimuli to their wings. In contrast, virgin female flies being courted by a male show a compromised defensive response to the stimuli, but following mating the response is enhanced. This state-dependent switch is mediated by a functional reconfiguration of a neural circuit labelled with the Tmc-L gene in the ventral nerve cord. The circuit receives excitatory inputs from peripheral mechanoreceptors and coordinates the defensive response. While male cues suppress it via a doublesex (dsx) neuronal pathway, mating sensitizes it by stimulating a group of uterine neurons and consequently activating a leucokinin-dependent pathway. Such a modulation is crucial for the balance between defense against body contacts and sexual receptivity.


Assuntos
Drosophila melanogaster/fisiologia , Vias Neurais/fisiologia , Comportamento Sexual Animal/fisiologia , Alelos , Animais , Corte , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Feminino , Neurônios GABAérgicos/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Mecanorreceptores/metabolismo , Mutação/genética , Neuropeptídeos/metabolismo , Útero/inervação , Asas de Animais/inervação
15.
Am Nat ; 196(2): 180-196, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32673091

RESUMO

Sexual selection studies widely estimate several metrics, but values may be inaccurate because standard field methods for studying wild populations produce limited data (e.g., incomplete sampling, inability to observe copulations directly). We compared four selection metrics (Bateman gradient, opportunity for sexual selection, opportunity for selection, and smax') estimated with simulated complete and simulated limited data for 15 socially monogamous songbird species with extrapair paternity (4%-54% extrapair offspring). Inferring copulation success from offspring parentage creates nonindependence between these variables and systematically underestimates copulation success. We found that this introduces substantial bias for the Bateman gradient, opportunity for sexual selection, and smax'. Notably, 47.5% of detected Bateman gradients were significantly positive for females, suggesting selection on females to copulate with multiple males, although the true Bateman gradient was zero. Bias generally increased with the extent of other sources of data limitations tested (nest predation, male infertility, and unsampled floater males). Incomplete offspring sampling introduced bias for all of the metrics except the Bateman gradient, while incomplete sampling of extrapair sires did not introduce additional bias when sires were a random subset of breeding males. Overall, our findings demonstrate how biases due to field data limitations can strongly impact the study of sexual selection.


Assuntos
Seleção Genética , Comportamento Sexual Animal/fisiologia , Aves Canoras/fisiologia , Animais , Viés , Simulação por Computador , Copulação , Feminino , Masculino , Aves Canoras/genética
16.
Nat Neurosci ; 23(9): 1111-1124, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32719562

RESUMO

Sexual and aggressive behaviors are fundamental to animal survival and reproduction. The medial preoptic nucleus (MPN) and ventrolateral part of the ventromedial hypothalamus (VMHvl) are essential regions for male sexual and aggressive behaviors, respectively. While key inhibitory inputs to the VMHvl and MPN have been identified, the extrahypothalamic excitatory inputs essential for social behaviors remain elusive. Here we identify estrogen receptor alpha (Esr1)-expressing cells in the posterior amygdala (PA) as a main source of excitatory inputs to the hypothalamus and key mediators for mating and fighting in male mice. We find two largely distinct PA subpopulations that differ in connectivity, gene expression, in vivo responses and social behavior relevance. MPN-projecting PAEsr1+ cells are activated during mating and are necessary and sufficient for male sexual behaviors, while VMHvl-projecting PAEsr1+ cells are excited during intermale aggression and promote attacks. These findings place the PA as a key node in both male aggression and reproduction circuits.


Assuntos
Agressão/fisiologia , Tonsila do Cerebelo/fisiologia , Vias Neurais/fisiologia , Comportamento Sexual Animal/fisiologia , Tonsila do Cerebelo/citologia , Animais , Hipotálamo/citologia , Hipotálamo/fisiologia , Masculino , Camundongos , Vias Neurais/citologia , Neurônios/citologia , Neurônios/fisiologia
17.
Proc Natl Acad Sci U S A ; 117(29): 17094-17103, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32611817

RESUMO

Declining ejaculate performance with male age is taxonomically widespread and has broad fitness consequences. Ejaculate success requires fully functional germline (sperm) and soma (seminal fluid) components. However, some aging theories predict that resources should be preferentially diverted to the germline at the expense of the soma, suggesting differential impacts of aging on sperm and seminal fluid and trade-offs between them or, more broadly, between reproduction and lifespan. While harmful effects of male age on sperm are well known, we do not know how much seminal fluid deteriorates in comparison. Moreover, given the predicted trade-offs, it remains unclear whether systemic lifespan-extending interventions could ameliorate the declining performance of the ejaculate as a whole. Here, we address these problems using Drosophila melanogaster. We demonstrate that seminal fluid deterioration contributes to male reproductive decline via mating-dependent mechanisms that include posttranslational modifications to seminal proteins and altered seminal proteome composition and transfer. Additionally, we find that sperm production declines chronologically with age, invariant to mating activity such that older multiply mated males become infertile principally via reduced sperm transfer and viability. Our data, therefore, support the idea that both germline and soma components of the ejaculate contribute to male reproductive aging but reveal a mismatch in their aging patterns. Our data do not generally support the idea that the germline is prioritized over soma, at least, within the ejaculate. Moreover, we find that lifespan-extending systemic down-regulation of insulin signaling results in improved late-life ejaculate performance, indicating simultaneous amelioration of both somatic and reproductive aging.


Assuntos
Envelhecimento , Drosophila melanogaster , Proteínas de Plasma Seminal , Espermatozoides , Envelhecimento/genética , Envelhecimento/fisiologia , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Feminino , Fertilidade/genética , Fertilidade/fisiologia , Infertilidade Masculina/genética , Infertilidade Masculina/fisiopatologia , Masculino , Proteoma/análise , Proteoma/genética , Proteoma/fisiologia , Proteínas de Plasma Seminal/análise , Proteínas de Plasma Seminal/fisiologia , Comportamento Sexual Animal/fisiologia , Espermatozoides/química , Espermatozoides/fisiologia
18.
Exp Anim ; 69(4): 441-447, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-32611932

RESUMO

Among the intact male rats, a subpopulation has been found to show little or no sexual behavior, even after experiencing several mating sessions. This study investigated whether sexually sluggish (SS) males show behavioral differences from normal copulatory (NC) males, other than those concerning sexual behavior. The olfactory preference of males was measured through the time spent displaying nose-poking behavior directed at sexually active males and estrous females for odor exploration in a three-chamber apparatus. Both the NC and SS males showed a significant preference for the odor of estrous females compared with that of male odors. However, SS males spent significantly less time nose-poking estrous females than NC males. The food-finding test was performed after overnight fasting. Our findings showed that all the NC males found the buried pellet within 5 min, whereas over 60% of the SS males failed to find it. The males were also tested for their ability to find a buried bag containing soiled bedding from estrous female cages. The bag was found by 80% of NC males, but only by 20% of SS males. Our results suggest that SS and NC male rats differ not only in sexual behavior but also in other functions such as olfaction.


Assuntos
Copulação/fisiologia , Odorantes , Ratos Long-Evans/psicologia , Comportamento Sexual Animal/fisiologia , Olfato/fisiologia , Animais , Ciclo Estral , Feminino , Humanos , Masculino
19.
PLoS One ; 15(6): e0233756, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497098

RESUMO

Habitat selection links individual behavior to population abundance and dynamics, so evaluation of habitat selection is necessary for conservation and management. Land management can potentially alter both the structure and composition of habitats, thus influencing habitat selection and population size. Livestock grazing is the dominant land use worldwide and, while overstocking has been linked to the decline of many wildlife species, properly managed grazing could improve habitat quality and maintain native rangeland habitats. We evaluated breeding season habitat selection of female sharp-tailed grouse, an indicator species for grassland ecosystems, in relation to grazing management and landscape features in eastern Montana and western North Dakota. At broad spatial scales, females selected for multiple landscape features, including grassland, but exhibited no selection for either landscape or management variables when selecting habitat at smaller spatial scales. Females selected for pastures managed with rest-rotation grazing when choosing a home range, but selection did not equate to improved fitness. Moreover, we observed strong individual variation in both home range size and third-order habitat selection. While the high variability among individuals makes specific management recommendations difficult, selection for grassland habitats at broad scales suggests that strategies that maintain intact native rangelands are important for the conservation of sharp-tailed grouse.


Assuntos
Conservação dos Recursos Naturais/métodos , Galliformes/fisiologia , Pradaria , Aves Domésticas , Animais , Teorema de Bayes , Feminino , Comportamento de Retorno ao Território Vital , Modelos Lineares , Montana , North Dakota , Dinâmica Populacional , Comportamento Sexual Animal/fisiologia
20.
Toxicol Appl Pharmacol ; 401: 115077, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32479917

RESUMO

Triclocarban (TCC) is an antimicrobial compound, widely used in personal care products, such as soaps, toothpaste, and shampoo. This agent is incompletely removed by wastewater treatment and represents an environmental contaminant. Studies show that TCC has been associated with some endocrine disruptions. In vitro, TCC demonstrated potent androgen-augmenting activity and aromatase inhibition. In this sense, exposure during critical periods of development (gestation and lactation) could lead to some adverse health outcomes in offspring. Therefore, the present study evaluated if maternal exposure to three different doses of TCC could interfere in the reproductive parameters of male offspring. Pregnant female Wistar rats were separated into four groups: vehicle Control (CTR); TCC 0.3 mg/kg (TCC 0.3); TCC 1.5 mg/kg (TCC 1.5); TCC 3.0 mg/kg (TCC 3.0). Dams were treated daily by oral gavage from gestational day 0 to lactational day 21. The males were evaluated in different timepoint: infancy (PND 21), puberty (PND 50) and adult life (PND 90-120). The histomorphometric analysis of testis and testosterone level were assessed on PND 21, 50, 120; sexual behavior and sperm parameters at adulthood. In the TCC 3.0 group, a decrease in the testis interstitial volume and an increase in testosterone levels were observed on PND 21. Moreover, there was a decrease in the diameter of the seminiferous tubules on PND 50, and a decrease in sexual competency in adulthood. These results suggest that exposure to a human relevant dose of TCC may interfere with reproduction and could have implications for human health.


Assuntos
Anti-Infecciosos Locais/toxicidade , Carbanilidas/toxicidade , Lactação/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Reprodução/efeitos dos fármacos , Comportamento Sexual Animal/efeitos dos fármacos , Fatores Etários , Animais , Feminino , Lactação/fisiologia , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos , Ratos Wistar , Reprodução/fisiologia , Comportamento Sexual Animal/fisiologia , Testículo/efeitos dos fármacos , Testículo/patologia , Testosterona/sangue
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