Middleborns disadvantaged? testing birth-order effects on fitness in pre-industrial finns

Parental investment is a limited resource for which offspring compete in order to increase their own survival and reproductive success. However, parents might be selected to influence the outcome of sibling competition through differential investment. While evidence for this is widespread in egg-laying species, whether or not this may also be the case in viviparous species is more difficult to determine. We use pre-industrial Finns as our model system and an equal investment model as our null hypothesis, which predicts that (all else being equal) middleborns should be disadvantaged through competition. We found no overall evidence to suggest that middleborns in a family are disadvantaged in terms of their survival, age at first reproduction or lifetime reproductive success. However, when considering birth-order only among same-sexed siblings, first-, middle-and lastborn sons significantly differed in the number of offspring they were able to rear to adulthood, although there was no similar effect among females. Middleborn sons appeared to produce significantly less offspring than first-or lastborn sons, but they did not significantly differ from lastborn sons in the number of offspring reared to adulthood. Our results thus show that taking sex differences into account is important when modelling birth-order effects. We found clear evidence of firstborn sons being advantaged over other sons in the family, and over firstborn daughters. Therefore, our results suggest that parents invest differentially in their offspring in order to both preferentially favour particular offspring or reduce offspring inequalities arising from sibling competition

Evolution de la douleur au cours du programme européen d'éducation à la santé EFFICHRONIC, chez des patients vulnérables, et atteints de maladie chronique

Chronic pain affects a large part of the population, with considerable consequences onthe quality of life, inducing physical and psycho-social vulnerabilities. It causes direct coststhrough treatments, and indirect costs through reduced productivity of the patients.Reciprocally, pain is impacted by psychological and socioeconomic factors. Chronic conditionscan be improved by reducing modifiable risk factors. Several education programs, such as theChronic Disease Self-Management Program (CDSMP), have shown benefits of patientempowerment and health literacy. However, in vulnerable populations, the impact of suchprograms has received little attention, although prevalence of chronic conditions issignificantly higher. The present research is the first multicentric evaluation of the ability ofthe CDSMP to improve pain. It is based on the project EFFICHRONIC, involving socioeconomicallyvulnerable participants, with a chronic condition, in five European countries.Adjusting for a wide range of variables, and using multiple imputation methods for morethan a thousand participants, we found that pain was significantly lowered after theintervention (in both complete cases and imputed datasets). Although the effect size wasweak, our results support the idea that such training programs are able to improve pain andalleviate its consequences on quality of life, particularly in vulnerable populations. Thebenefits of the intervention appeared to be greater for younger participants, and those witha higher education level. Such specificities of our target population reinforce the idea thatthe recognition of the social determinants of health is essential.La douleur chronique touche une grande partie de la population, avec des conséquencesconsidérables sur la qualité de vie, induisant des vulnérabilités physiques et psychosociales.Elle entraîne des coûts directs via les traitements, et des indirects via une productivitéréduite des patients. Réciproquement, la douleur est impactée par des facteurspsychologiques et socio-économiques. Les conditions chroniques peuvent être améliorées enréduisant les facteurs de risque modifiables, et plusieurs programmes d'éducation à la santé,tels que le Chronic Disease Self-Management Program (CDSMP), ont montré qu’ils pouvaientêtre bénéfiques. Cependant, dans les populations vulnérables, bien que la prévalence desmaladies chroniques soit nettement plus élevée, l'impact de ces programmes a reçu peud'attention. Cette étude est la première évaluation multicentrique de la capacité du CDSMPà améliorer la douleur. Elle s’inscrit dans le projet européen EFFICHRONIC, impliquant desparticipants socio-économiquement vulnérables, atteints d'une maladie chronique, dans cinqpays européens. En ajustant pour un large éventail de variables, sur un échantillon de plusde mille participants, nous avons constaté que la douleur était significativement réduiteaprès l'intervention. Même si la taille d’effet était faible, nos résultats soutiennent l'idée quede tels programmes sont capables d'améliorer la douleur et d'atténuer ses conséquences surla qualité de vie, en particulier dans les populations vulnérables. Les avantages del'intervention semblaient être plus importants pour les participants plus jeunes, et quiavaient un niveau d’études plus élevé. Ces spécificités de notre population cible renforcentl'idée que la reconnaissance des déterminants sociaux de la santé est essentielle

Evolution de la douleur au cours du programme européen d'éducation à la santé EFFICHRONIC, chez des patients vulnérables, et atteints de maladie chronique

Chronic pain affects a large part of the population, with considerable consequences onthe quality of life, inducing physical and psycho-social vulnerabilities. It causes direct coststhrough treatments, and indirect costs through reduced productivity of the patients.Reciprocally, pain is impacted by psychological and socioeconomic factors. Chronic conditionscan be improved by reducing modifiable risk factors. Several education programs, such as theChronic Disease Self-Management Program (CDSMP), have shown benefits of patientempowerment and health literacy. However, in vulnerable populations, the impact of suchprograms has received little attention, although prevalence of chronic conditions issignificantly higher. The present research is the first multicentric evaluation of the ability ofthe CDSMP to improve pain. It is based on the project EFFICHRONIC, involving socioeconomicallyvulnerable participants, with a chronic condition, in five European countries.Adjusting for a wide range of variables, and using multiple imputation methods for morethan a thousand participants, we found that pain was significantly lowered after theintervention (in both complete cases and imputed datasets). Although the effect size wasweak, our results support the idea that such training programs are able to improve pain andalleviate its consequences on quality of life, particularly in vulnerable populations. Thebenefits of the intervention appeared to be greater for younger participants, and those witha higher education level. Such specificities of our target population reinforce the idea thatthe recognition of the social determinants of health is essential.La douleur chronique touche une grande partie de la population, avec des conséquencesconsidérables sur la qualité de vie, induisant des vulnérabilités physiques et psychosociales.Elle entraîne des coûts directs via les traitements, et des indirects via une productivitéréduite des patients. Réciproquement, la douleur est impactée par des facteurspsychologiques et socio-économiques. Les conditions chroniques peuvent être améliorées enréduisant les facteurs de risque modifiables, et plusieurs programmes d'éducation à la santé,tels que le Chronic Disease Self-Management Program (CDSMP), ont montré qu’ils pouvaientêtre bénéfiques. Cependant, dans les populations vulnérables, bien que la prévalence desmaladies chroniques soit nettement plus élevée, l'impact de ces programmes a reçu peud'attention. Cette étude est la première évaluation multicentrique de la capacité du CDSMPà améliorer la douleur. Elle s’inscrit dans le projet européen EFFICHRONIC, impliquant desparticipants socio-économiquement vulnérables, atteints d'une maladie chronique, dans cinqpays européens. En ajustant pour un large éventail de variables, sur un échantillon de plusde mille participants, nous avons constaté que la douleur était significativement réduiteaprès l'intervention. Même si la taille d’effet était faible, nos résultats soutiennent l'idée quede tels programmes sont capables d'améliorer la douleur et d'atténuer ses conséquences surla qualité de vie, en particulier dans les populations vulnérables. Les avantages del'intervention semblaient être plus importants pour les participants plus jeunes, et quiavaient un niveau d’études plus élevé. Ces spécificités de notre population cible renforcentl'idée que la reconnaissance des déterminants sociaux de la santé est essentielle

Evolution de la douleur au cours du programme européen d'éducation à la santé EFFICHRONIC, chez des patients vulnérables, et atteints de maladie chronique

Chronic pain affects a large part of the population, with considerable consequences onthe quality of life, inducing physical and psycho-social vulnerabilities. It causes direct coststhrough treatments, and indirect costs through reduced productivity of the patients.Reciprocally, pain is impacted by psychological and socioeconomic factors. Chronic conditionscan be improved by reducing modifiable risk factors. Several education programs, such as theChronic Disease Self-Management Program (CDSMP), have shown benefits of patientempowerment and health literacy. However, in vulnerable populations, the impact of suchprograms has received little attention, although prevalence of chronic conditions issignificantly higher. The present research is the first multicentric evaluation of the ability ofthe CDSMP to improve pain. It is based on the project EFFICHRONIC, involving socioeconomicallyvulnerable participants, with a chronic condition, in five European countries.Adjusting for a wide range of variables, and using multiple imputation methods for morethan a thousand participants, we found that pain was significantly lowered after theintervention (in both complete cases and imputed datasets). Although the effect size wasweak, our results support the idea that such training programs are able to improve pain andalleviate its consequences on quality of life, particularly in vulnerable populations. Thebenefits of the intervention appeared to be greater for younger participants, and those witha higher education level. Such specificities of our target population reinforce the idea thatthe recognition of the social determinants of health is essential.La douleur chronique touche une grande partie de la population, avec des conséquencesconsidérables sur la qualité de vie, induisant des vulnérabilités physiques et psychosociales.Elle entraîne des coûts directs via les traitements, et des indirects via une productivitéréduite des patients. Réciproquement, la douleur est impactée par des facteurspsychologiques et socio-économiques. Les conditions chroniques peuvent être améliorées enréduisant les facteurs de risque modifiables, et plusieurs programmes d'éducation à la santé,tels que le Chronic Disease Self-Management Program (CDSMP), ont montré qu’ils pouvaientêtre bénéfiques. Cependant, dans les populations vulnérables, bien que la prévalence desmaladies chroniques soit nettement plus élevée, l'impact de ces programmes a reçu peud'attention. Cette étude est la première évaluation multicentrique de la capacité du CDSMPà améliorer la douleur. Elle s’inscrit dans le projet européen EFFICHRONIC, impliquant desparticipants socio-économiquement vulnérables, atteints d'une maladie chronique, dans cinqpays européens. En ajustant pour un large éventail de variables, sur un échantillon de plusde mille participants, nous avons constaté que la douleur était significativement réduiteaprès l'intervention. Même si la taille d’effet était faible, nos résultats soutiennent l'idée quede tels programmes sont capables d'améliorer la douleur et d'atténuer ses conséquences surla qualité de vie, en particulier dans les populations vulnérables. Les avantages del'intervention semblaient être plus importants pour les participants plus jeunes, et quiavaient un niveau d’études plus élevé. Ces spécificités de notre population cible renforcentl'idée que la reconnaissance des déterminants sociaux de la santé est essentielle

Evolution du polymorphisme de latéralité dans les populations humaines

MONTPELLIER-BU Sciences (341722106) / SudocSudocFranceF

Handedness: Neutral or adaptive?

International audienceCorballis seems to have not considered two points: (1) the importance of direct selection pressures for the evolution of handedness; and (2) the evolutionary significance of the polymorphism of handedness. We provide arguments for the need to explain handedness in terms of adaptation and natural selection

The fighting hypothesis as an evolutionary explanation for the handedness polymorphism in humans: where are we?

International audienceThe ubiquitous and persistent handedness polymorphism in humans requires an evolutionary explanation. It has been suggested that left-handers have a frequency-dependent advantage during a fight, such that this advantage decreases when their frequency increases. Many independent studies are providing data from interactive sports (a specific class of fights), and are very supportive of the fighting hypothesis. The only intercultural study on traditional societies is also consistent with the fighting hypothesis, although it has not yet been replicated. The frequencies of left-handers in the few remaining violent societies are likely to be rapidly decreasing, due to Western colonization (long-range weapons, religion, and money market) dramatically affecting the frequency-dependent selection associated with handedness. Clearly, more data are urgently needed outside the Western influence