RESUMEN
Despite the far-reaching evolutionary implications of sexual conflict, the effects of metapopulation structure, when populations are subdivided into several demes connected to some degree by migration, on sexual conflict dynamics are unknown. Here, we used experimental evolution in an insect model system, the seed beetle Callosobruchus maculatus, to assess the independent and interacting effects of selection histories associated with mating system (monogamy vs. polygamy) and population subdivision on sexual conflict evolution. We confirm traditional predictions from sexual conflict theory by revealing increased resistance to male harm in females from populations with a history of intense sexual selection (polygamous populations) compared to females from populations with a history of relaxed sexual selection (monogamous populations). However, selection arising from metapopulation structure reversed the classic pattern of sexually antagonistic coevolution and led to reduced resistance in females from polygamous populations. These results underscore that population spatial structure moderates sexual selection and sexual conflict, and more broadly, that the evolution of sexual conflict is contingent on ecological context. The findings also have implications for population dynamics, conservation biology, and biological control.
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Understanding and forecasting the effects of environmental change on wild populations requires knowledge on a critical question: do populations have the ability to evolve in response to that change? However, our knowledge on how evolution works in wild conditions under different environmental circumstances is extremely limited. We investigated how environmental variation influences the evolutionary potential of phenotypic traits. We used published data to collect or calculate 135 estimates of evolvability of morphological traits of European wild bird populations. We characterized the environmental favourability of each population throughout the species' breeding distribution. Our results suggest that the evolutionary potential of morphological traits decreases as environmental favourability becomes high or low. Strong environmental selection pressures and high intra-specific competition may reduce species' evolutionary potential in low- and high- favourability areas, respectively. This suggests that species may be least able to adapt to new climate conditions at their range margins and at the centre. Our results underscore the need to consider the evolutionary potential of populations when studying the drivers of species distributions, particularly when predicting the effects of environmental change. We discuss the utility of integrating evolutionary dynamics into a biogeographical perspective to understand how environmental variation shapes evolutionary patterns. This approach would also produce more reliable predictions about the effect of environmental change on population persistence and therefore on biodiversity.
Asunto(s)
Evolución Biológica , Aves , Ambiente , Animales , Biodiversidad , Geografía , FenotipoRESUMEN
It is well known that sexual selection can target reproductive traits during successive pre- and post-mating episodes of selection. A key focus of recent studies has been to understand and quantify how these episodes of sexual selection interact to determine overall variance in reproductive success. In this article, we review empirical developments in this field but also highlight the considerable variability in patterns of pre- and post-mating sexual selection, attributable to variation in patterns of resource acquisition and allocation, ecological and social factors, genotype-by-environment interaction and possible methodological factors that might obscure such patterns. Our aim is to highlight how (co)variances in pre- and post-mating sexually selected traits can be sensitive to changes in a range of ecological and environmental variables. We argue that failure to capture this variation when quantifying the opportunity for sexual selection may lead to erroneous conclusions about the strength, direction or form of sexual selection operating on pre- and post-mating traits. Overall, we advocate for approaches that combine measures of pre- and post-mating selection across contrasting environmental or ecological gradients to better understand the dynamics of sexual selection in polyandrous species. We also discuss some directions for future research in this area.
Asunto(s)
Fenotipo , Reproducción , Conducta Sexual Animal , Animales , Conducta SexualRESUMEN
When females mate polyandrously, male reproductive success depends both on the male's ability to attain matings and on his ability to outcompete rival males in the fertilization of ova post-copulation. Increased investment in ejaculate components may trade off with investment in precopulatory traits due to resource allocation. Alternatively, pre- and post-copulatory traits could be positively related if individuals can afford to invest heavily in traits advantageous at both episodes of selection. There is empirical evidence for both positive and negative associations between pre- and post-copulatory episodes, but little is known about the genetic basis of these correlations. In this study, we measured morphological, chemical and behavioural precopulatory male traits and investigated their relationship with measures of male fitness (male mating success, remating inhibition and offensive sperm competitiveness) across 40 isofemale lines of Drosophila melanogaster. We found significant variation among isofemale lines, indicating a genetic basis for most of the traits investigated. However, we found weak evidence for genetic correlations between precopulatory traits and our indices of male fitness. Moreover, pre- and post-copulatory episodes of selection were uncorrelated, suggesting selection may act independently at the different episodes to maximize male reproductive success.
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Copulación , Drosophila melanogaster/genética , Variación Genética , Animales , Femenino , Masculino , Reproducción , Selección Genética , Conducta Sexual AnimalRESUMEN
Polyandry is widespread despite its costs. The sexually selected sperm hypotheses ('sexy' and 'good' sperm) posit that sperm competition plays a role in the evolution of polyandry. Two poorly studied assumptions of these hypotheses are the presence of additive genetic variance in polyandry and sperm competitiveness. Using a quantitative genetic breeding design in a natural population of Drosophila melanogaster, we first established the potential for polyandry to respond to selection. We then investigated whether polyandry can evolve through sexually selected sperm processes. We measured lifetime polyandry and offensive sperm competitiveness (P2 ) while controlling for sampling variance due to male × male × female interactions. We also measured additive genetic variance in egg-to-adult viability and controlled for its effect on P2 estimates. Female lifetime polyandry showed significant and substantial additive genetic variance and evolvability. In contrast, we found little genetic variance or evolvability in P2 or egg-to-adult viability. Additive genetic variance in polyandry highlights its potential to respond to selection. However, the low levels of genetic variance in sperm competitiveness suggest that the evolution of polyandry may not be driven by sexy sperm or good sperm processes.
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Variación Genética , Conducta Sexual Animal , Espermatozoides/fisiología , Animales , Evolución Biológica , Drosophila melanogaster/genética , Femenino , MasculinoRESUMEN
In many species, females exposed to increased sexual activity experience reductions in longevity. Here, in Drosophila melanogaster, we report an additional effect on females brought about by sexual interactions, an effect that spans generations. We subjected females to a sexual treatment consisting of different levels of sexual activity and then investigated patterns of mortality in their offspring. We found reduced probabilities of survival, increases in the rate of senescence and a pattern of reduced mean longevities, for offspring produced by mothers that experienced higher levels of sexual interaction. We contend that these effects constitute trans-generational costs of sexual conflict--the existence or implications of which have rarely been considered previously. Our results indicate that ongoing exposure by mothers to male precopulatory interactions is itself sufficient to drive trans-generational effects on offspring mortality. Thus, we show that increases in maternal sexual activity can produce trans-generational effects that permeate through to latter life stages in the offspring. This helps to elucidate the complex interplay between sex and ageing and provides new insights into the dynamics of adaptation under sexual selection.
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Envejecimiento/fisiología , Drosophila melanogaster/fisiología , Conducta Sexual Animal/fisiología , Animales , Femenino , Masculino , ReproducciónRESUMEN
Sexual conflict facilitates the evolution of traits that increase the reproductive success of males at the expense of components of female fitness. Theory suggests that indirect benefits are unlikely to offset the direct costs to females from antagonistic male adaptations, but empirical studies examining the net fitness pay-offs of the interaction between the sexes are scarce. Here, we investigate whether matings with males that invest intrinsically more into accessory gland tissue undermine female lifetime reproductive success (LRS) in the cricket Teleogryllus oceanicus. We found that females incur a longevity cost of mating that is proportional to the partner's absolute investment into the production of accessory gland products. However, male accessory gland weight positively influences embryo survival, and harmful ejaculate-induced effects are cancelled out when these are put in the context of female LRS. The direct costs of mating with males that sire offspring with higher viability are thus compensated by direct and possibly indirect genetic benefits in this species.
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Embrión no Mamífero/fisiología , Gryllidae/fisiología , Longevidad , Semen/fisiología , Conducta Sexual Animal , Animales , Evolución Biológica , Femenino , Fertilidad , Masculino , Oviparidad , Selección GenéticaRESUMEN
A growing number of studies are suggesting that females can improve the viability of their embryos by mating with multiple males. However, the reason why females should have low rates of embryo viability is puzzling. Here we conduct a quantitative genetic study of maternal effects on embryo viability in the field cricket Teleogryllus oceanicus. After controlling for female body size, we find significant additive genetic variance for ovary weight, a measure of fecundity, and egg hatching success, a measure of embryo viability. Moreover, we show a genetic trade-off between these traits that is predicted from life-history theory. High rates of embryo mortality in this highly fecund species might therefore be explained by selection favouring an optimum balance between fecundity and embryo viability that maximizes maternal fitness. Paternal effects on female fecundity and embryo viability are often seen as benefits driving the evolution of polyandrous behaviour. However, we raise the alternative possibility that paternal effects might shift females from their naturally selected optimum, and present some support for the notion that sexual conflict over a female's optimal fecundity and embryo viability might generate antagonistic coevolution between the sexes.
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Gryllidae/fisiología , Animales , Tamaño Corporal , Femenino , Fertilidad , Gryllidae/genética , Masculino , Ovario/fisiologíaRESUMEN
Females typically mate with more than one male despite the costs incurred, thus questioning Bateman's principle. A series of genetic benefits have been proposed to account for the evolution of polyandry, including the acquisition of viability genes for offspring. The 'intrinsic male quality' hypothesis suggests that polyandry increases the probability that females produce offspring sired by males that bestow high viability on their offspring. Heritable variation in viability is the basic requirement for the occurrence of this genetic benefit. By using a half-sib breeding design with a species of cricket in which polyandry is known to increase hatching success, we present clear experimental evidence that intrinsic male quality contributes to embryo viability. Despite recent support for the evolution of polyandry based on compatibility of genotypes between males and females, we show that hatching success is not determined by an interaction between paternal and maternal genotypes but rather that sons inherit paternal genes that influence the viability of eggs laid by their mates. Moreover, our data implicate a potential role for indirect genetic effects of male accessory gland products on embryo viability. Additive genetic contributions to embryo viability may be an important factor underlying the frequently observed benefits of polyandrous behaviour.
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Evolución Biológica , Gryllidae/fisiología , Conducta Sexual Animal/fisiología , Análisis de Varianza , Animales , Cruzamiento , Femenino , Fertilidad/fisiología , Genotipo , Gryllidae/genética , Masculino , Óvulo/fisiología , Factores Sexuales , Espermatozoides/fisiologíaRESUMEN
OBJECTIVE: To compare and quantify intravenous omeprazole versus intravenous pantoprazole prescription habits in common acid-related diseases such as gastro-esophageal reflux disease, duodenal ulcer, and gastric ulcer. MATERIAL AND METHODS: We designed an observational, longitudinal prospective and multicenter cost-minimization study to be carried out in Spanish hospitals. RESULTS: The pantoprazole regimen consisted of 40 mg/day (median), one half of that of omeprazole with 80 mg/day overall for these conditions (p < 0.05). This dosage was significantly different for duodenal ulcer (40.0 +/- 0.0 versus 90.6 +/- 22.5 mg/day, p < 0.05), and gastric ulcer (50.3 +/- 17.8 versus 85.8 +/- 39 mg/day, p < 0.05), but not for gastro-esophageal reflux disease (50.9 +/- 18.7 versus 62.2 +/- 21.1, p > 0.05). Costs for these regimens make treatments using pantoprazole 54% less expensive than treatments using omeprazole. By indication, the cost of duodenal ulcer treatment was 65% less expensive, and that of gastric ulcer 53% less expensive. CONCLUSIONS: Cost differences amount to approximately one half in treatments using pantoprazole, which is primarily due to the use of doses higher than indicated in treatments using intravenous omeprazole. To reduce expenses stemming from the inadequate use of intravenous proton pump inhibitors the use of pantoprazole is brought forward as a valid option.
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Bencimidazoles/economía , Bencimidazoles/uso terapéutico , Inhibidores Enzimáticos/economía , Inhibidores Enzimáticos/uso terapéutico , Omeprazol/economía , Omeprazol/uso terapéutico , Sulfóxidos/economía , Sulfóxidos/uso terapéutico , 2-Piridinilmetilsulfinilbencimidazoles , Anciano , Costos y Análisis de Costo , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pantoprazol , Estudios Prospectivos , Inhibidores de la Bomba de ProtonesRESUMEN
BACKGROUND: Few cases of allergy to pine nuts have been described. We report a case of anaphylactic reaction to pine nuts. The patient needed to be treated in the emergency room due to a systemic reaction immediately after eating pine nuts. METHODS: The patient was studied by prick tests and prick by prick tests. Specific IgE was measured by CAP and by SDS-PAGE/immunoblotting by a diffusion method. RESULTS: The patient showed positive prick by prick tests to pine nuts (12 mm of maximum wheal diameter). Specific IgE was positive (0.79 kU/l). The patient's serum recognized several proteins by immunoblot. However, a 17-kDa allergen band was detected with high intensity. This protein was found to be sensitive to reducing agents, losing its IgE-binding properties after reduction. CONCLUSIONS: The patient presented an IgE-mediated reaction and detected a 17-kDa protein from pine nuts not previously described.
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Alérgenos/efectos adversos , Anafilaxia/etiología , Hipersensibilidad a los Alimentos/etiología , Nueces/efectos adversos , Adulto , Alérgenos/química , Alérgenos/inmunología , Anafilaxia/inmunología , Electroforesis en Gel de Poliacrilamida , Hipersensibilidad a los Alimentos/inmunología , Humanos , Immunoblotting , Inmunoglobulina E/análisis , Pruebas Intradérmicas , Masculino , Peso Molecular , Proteínas de Plantas/efectos adversos , Proteínas de Plantas/química , Proteínas de Plantas/inmunologíaRESUMEN
We report the case of a woman who developed generalized dermatitis after 1 week of treatment with ebrotidine, a new H2-receptor antagonist taken to prevent gastroduodenal lesions caused by nonsteroidal inflammatory drugs. Patch tests with ebrotidine and other H2-receptor antagonists ranitidine, cimetidine and famotidine were negative. Oral challenge test with ebrotidine showed the development of lesions similar to those appearing previously. Oral challenge test with ranitidine and cimetidine were negative, possibly due to the difference in the side chain chemical structure of ebrotidine and other H2-receptor antagonists. This is the first reported case of allergic dermatitis caused by ebrotidine.
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Bencenosulfonatos/efectos adversos , Dermatitis/etiología , Erupciones por Medicamentos/etiología , Hipersensibilidad a las Drogas/etiología , Tiazoles/efectos adversos , Administración Oral , Antiulcerosos/efectos adversos , Bencenosulfonatos/administración & dosificación , Femenino , Antagonistas de los Receptores H2 de la Histamina/efectos adversos , Humanos , Persona de Mediana Edad , Tiazoles/administración & dosificaciónAsunto(s)
Anisakis , Dermatitis Alérgica por Contacto/etiología , Productos Pesqueros/efectos adversos , Dermatosis de la Mano/etiología , Anciano , Animales , Dermatitis Alérgica por Contacto/diagnóstico , Femenino , Peces/parasitología , Dermatosis de la Mano/diagnóstico , Humanos , Pruebas del Parche , Proteínas/efectos adversosRESUMEN
PIP: The author reviews family characteristics in Zacatecas, Mexico, during the early decades of the nineteenth century using data from a census conducted in 1827.^ieng
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Composición Familiar , Américas , Países en Desarrollo , América Latina , México , América del NorteRESUMEN
The objective of this study, is to confirm a clear benefit of protein synthesis after administration of branched amino acids in parenteral nutrition solutions. Particularly, on a parenteral total hypocaloric nutrition including lipids. Eighty one digestive surgical patients, were included in this study. Fifty with neoplastic disease and thirty one without. Patients in both study groups received a similar peripheral vein nutritional support regimen one week after surgical treatment. To evaluate the effects of the branched chain amino acid enrichment on total parenteral nutrition, we observed the behavior of short middle life proteins such as transferrin, prealbumin, and retinol binding protein, for their reliability as indexes of protein synthesis.
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Aminoácidos de Cadena Ramificada/administración & dosificación , Proteínas Sanguíneas/metabolismo , Enfermedades del Sistema Digestivo/terapia , Neoplasias del Sistema Digestivo/terapia , Nutrición Parenteral Total/métodos , Terapia Combinada , Enfermedades del Sistema Digestivo/sangre , Neoplasias del Sistema Digestivo/sangre , Estudios de Evaluación como Asunto , Humanos , Cuidados Posoperatorios/métodosRESUMEN
One of the generic indications of parenteral peripheral malnutrition is the immediate postoperative period following surgery of the digestive tract. In the series presented, fifty patients with digestive neoplasia of different locations were studied, with slight or moderate malnutrition upon admittance. After the operation, feeding was done using hypocaloric parenteral solutions for the first seven days of the postop. period. In the qualitative intake of nitrogen in this type of nutrition, branched chain amino acids are important due to their beneficial effects on metabolism, and for this reason two complete hypocaloric solutions containing 45% and 15.5% of these amino acids were administered to each respective group under study. To justify the effect of improving the proteic synthesis attributed to these amino acids, the levels of rapid turnover proteins, transferrin, prealbumin and retinol-binding protein were determined.
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Aminoácidos de Cadena Ramificada/administración & dosificación , Neoplasias del Sistema Digestivo/cirugía , Nutrición Parenteral , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Nutricionales/complicaciones , Trastornos Nutricionales/diagnóstico , Estado Nutricional , Periodo Posoperatorio , Soluciones , Factores de TiempoRESUMEN
Presentation of the first results obtained from our study, the objective of which is to discover a benefit in the nutritional state following the administration of a greater amount of branched chain amino-acids in parenteral solutions using the peripheral method, during the first 7 days of the postoperative period, in neoplastic patients subjected to surgery of the digestive tract.
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Aminoácidos de Cadena Ramificada/administración & dosificación , Nutrición Parenteral Total/métodos , Anciano , Anciano de 80 o más Años , Neoplasias del Sistema Digestivo/sangre , Neoplasias del Sistema Digestivo/terapia , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estado Nutricional , Cuidados PosoperatoriosRESUMEN
The case of a 72-year-old female with a syndrome of malabsorption associated with prurigo nodularis is reported. The patient had been suffering from these disorders for 16 years. The pathological alteration of her malabsorption syndrome was an idiopathic sprue. 5 months after treatment with gluten-free diet supplemented with vitamins and iron, the disappearance of the clinical and analytical alterations was complete.