Carotenoids are fat-soluble pigments synthesised by photosynthetic organisms(Brush,1990).Conversely,animals are incapable of synthesizing carotenoids de novo,and they must obtain them through their diet.However,some a...Carotenoids are fat-soluble pigments synthesised by photosynthetic organisms(Brush,1990).Conversely,animals are incapable of synthesizing carotenoids de novo,and they must obtain them through their diet.However,some animal species are able to make some alterations to the basic chemical structure,converting ingested carotenoids into more oxidized and differently coloured forms(Schiedt,1998).展开更多
A strong focus of ecological research for several decades has been to understand the factors underlying the variation in animal life-histories. In recent times, ecological studies have begun to show that oxidative str...A strong focus of ecological research for several decades has been to understand the factors underlying the variation in animal life-histories. In recent times, ecological studies have begun to show that oxidative stress may represent another important modulator of competitive trade-offs among fitness traits or of positively integrated patterns of traits. Therefore, incorporating mechanisms underlying oxidative physiology into evolutionary ecology has the potential to help understand variation in life-history strategies. In this review, I provide a general overview of oxidative stress physiology, and subsequently focus on topics that have been neglected in previous ecological reviews on oxidative stress. Specifically, I introduce and discuss the adaptations that animals have evolved to cope with oxidative stress; the environmental stressors that can generate changes in oxidative balance; the role of reactive species in transduction of environmental stimuli and cell signaling; and the range of hormetic responses to oxidative stress [Current Zoology 56 （6）： 687-702, 2010].展开更多
Oxidative stress is a key physiological mechanism underlying life-history tradeoffs. Here, I use meta-analytic techniques to test whether sexual differences in oxidative balance are common in vertebrates and to identi...Oxidative stress is a key physiological mechanism underlying life-history tradeoffs. Here, I use meta-analytic techniques to test whether sexual differences in oxidative balance are common in vertebrates and to identify which factors are associated with such differences. The dataset included 732 effect size estimates from 100 articles （82 species）. Larger unsigned effect size （meaning larger sexual differences in a given marker） occurred in： reptiles and fish; those species that do not pro- vide parental care; and oviparous species. Estimates of signed effect size （positive values meaning higher oxidative stress in males） indicated that females were less resistant to oxidative stress than males in： reptiles while males and females were similar in fish, birds, and mammals; those species that do not provide parental care; and oviparous species. There was no evidence for a significant sexual differentiation in oxidative balance in fish, birds, and mammals. Effect size was not associ- ated with： the number of offspring; whether the experimental animals were reproducing or not; biomarker （oxidative damage, non-enzymatic, or enzymatic antioxidant）, the species body mass; the strain （wild vs. domestic）; or the study environment （wild vs. captivity）. Oxidative stress tended to be higher in females than males across most of the tissues analyzed. Levels of residual heterogeneity were high in all models tested. The findings of this meta-analysis indicate that diversification of reproductive strategies might be associated with sexual differences in oxidative balance. This explorative meta-analysis offers a starting platform for future research to investigate the rela-tionship between sex and oxidative balance further.展开更多
Inbreeding negatively affects various life-history traits, with inbred individuals typically having lower fit- ness than outbred individuals （=inbreeding depression）. Inbreeding depression is often emphasized under ...Inbreeding negatively affects various life-history traits, with inbred individuals typically having lower fit- ness than outbred individuals （=inbreeding depression）. Inbreeding depression is often emphasized under environmental stress, but the underlying mechanisms and potential long-lasting consequences of such inbreeding-environment interactions remain poorly understood. Here, we hypothesize that inbreeding-environment interactions that occur early in life have long-term physiological effects, in partic- ular on the adult oxidative balance. We applied a unique experimental design to manipulate early life conditions of inbred and outbred songbirds （Serinus canaria） that allowed us to separate prenatal and postnatal components of early life conditions and their respective importance in inbreeding-environment interactions. We measured a wide variety of markers of oxidative status in adulthood, resulting in a com- prehensive account for oxidative balance. Using a Bayesian approach with Markov chain Monte Carlo, we found clear sex-specific effects and we also found only in females small yet significant long-term effects of inbreeding-environment interactions on adult oxidative balance. Postnatal components of early life conditions were most persuasively reflected on adult oxidative balance, with inbred females that experienced disadvantageous postnatal conditions upregulating enzymatic antioxidants in adulthood. Our study provides some evidence that adult oxidative balance can reflect inbreeding-environment inter- actions early in life, but given the rather small effects that were limited to females, we conclude that oxida- tive stress miaht have a limited role as mechanism underlvina inhre.e.dina-envirnnme.nt inte.raetinn.q_展开更多
Recent empirical and theoretical studies suggest that personality and locomotory performance traits linked to dispersal abilities are crucial components of the dispersal syndromes,and that they can evolve during range...Recent empirical and theoretical studies suggest that personality and locomotory performance traits linked to dispersal abilities are crucial components of the dispersal syndromes,and that they can evolve during range expansions and colonization processes.Island colonization is one of the best characterized processes in dispersal biogeography,and its implication in the evolution of phenotypic traits has been investigated over a wide range of temporal scales.However,the effect of island colonization on personality and performance traits of natural populations,and how these traits could drive island colonization,has been little explored.Noteworthy,no studies have addressed these processes in the context of late Pleistocene range expansions.Here,we investigated the contribution of island colonization triggered by postglacial range expansions to intraspecific variation in personality and locomotory performance traits.We compared boldness,exploration,jumping performance,and stickiness abilities in populations from 3 equidistant areas of the Tyrrhenian tree frog Hyla sarda,2 from the main island(Corsica Island),and 1 from the recently colonized island of Elba.Individuals from Elba were significantly bolder than individuals from Corsica,as they emerged sooner from a shelter(P=0.028),while individuals from Corsica showed markedly higher jumping and stickiness performance(both P<0.001),resulting as more performing than those of Elba.We discuss these results in the context of the major microevolutionary processes at play during range expansion,including selection,spatial sorting,founder effects,and their possible interaction with local adaptation processes.展开更多
An increasing trend in use of tracking devices such as geolocators is based on the assumption that the information gathered from such devices provides reliable information about the migratory behavior of free-living b...An increasing trend in use of tracking devices such as geolocators is based on the assumption that the information gathered from such devices provides reliable information about the migratory behavior of free-living birds. This underlying as- sumption is rarely tested, as evidenced by the absence in many studies of controls, in particular treated controls, and so far never with a reasonable statistical power. Published studies have shown reduced survival prospects or delayed breeding in some species, suggesting that there may be reason to doubt that tracking devices provide unbiased information. Therefore, we conducted a meta-analysis of studies applying geolocators to wild birds to determine whether geolocators affected fitness components. Ge- olocators had an overall negative effect on fitness components, in particular survival, and ecological variables. Effect size was larger for aerial foragers than for other species. Moreover the leg band attachment method was more detrimental for birds than the leg-loop backpack harness. A meta-regression model of effect size showed independent negative effects of geolocators on ae- rial foragers, smaller species, species with smaller migration distances and in studies where geolocators were attached with a ring. These results suggest that geolocator studies should be interpreted with caution, but also raise questions whether it is ethically defensible to use geolocators on aerial foragers or small species without carrying out robust pilot studies.展开更多
Many animal species migrate over long distances, but the physiological challenges of migration are poorly understood. It has recently been suggested that increased molecular oxidative damage might be one important cha...Many animal species migrate over long distances, but the physiological challenges of migration are poorly understood. It has recently been suggested that increased molecular oxidative damage might be one important challenge for migratory animals. We tested the hypothesis that autumn migration imposes an oxidative challenge to bats by comparing values of 4 blood-based markers of oxidative status (oxidative damage and both enzymatic and nonenzymatic antioxidants) between Nathusius' bats Pipistrellus nathusii that were caught during migration flights with those measured in conspecifics after resting for 18 or 24 h. Experiments were carried out at Pape Ornithological Station in Pape (Latvia) in 2016 and 2017. Our results show that flying bats have a blood oxidative status different from that of resting bats due to higher oxidative damage and different expression of both non enzymatic and enzymatic antioxidants (glutathione peroxidase). The differences in oxidative status markers varied betwee n sampli ng years and were in depende nt from in dividual body con dition or sex. Our work provides evidence that migratory flight might impose acute oxidative stress to bats and that resting helps animals to recover from oxidative damage accrued en route. Our data suggest that migrating bats and birds might share similar strategies of mitigating and recovering from oxidative stress.展开更多
Herpes viruses are responsible for a variety of pathological effects in humans and in both wild and domestic animals. One mechanism that has been proposed to facilitate replication and activity of herpes viruses is ox...Herpes viruses are responsible for a variety of pathological effects in humans and in both wild and domestic animals. One mechanism that has been proposed to facilitate replication and activity of herpes viruses is oxidative stress （OS）. We used meta-analytical techniques to test the hypotheses that （1） herpes virus infection causes OS and （2） supplementation of antioxidants reduces virus load, indicating that replication is favoured by a state of OS. Results based on studies on mammals, including humans, and birds show that （1） OS is indeed increased by herpes virus infection across multiple tissues and species, （2） biomarkers of OS may change differently between tissues, and （3） the effect size does not differ among different virus strains. In addition, the increase of oxidative damage in blood （tissue commonly available in ecological studies） was similar to that in the tissues most sensitive to the herpes virus. Our results also show that administration of antioxidants re- duces virus yield, indicating that a condition of OS is favorable for the viral replication. In addition, some antioxidants may be more efficient than others in reducing herpes virus yield. Our results point to a potential mechanism linking herpes virus infection to individual health status.展开更多
文摘Carotenoids are fat-soluble pigments synthesised by photosynthetic organisms(Brush,1990).Conversely,animals are incapable of synthesizing carotenoids de novo,and they must obtain them through their diet.However,some animal species are able to make some alterations to the basic chemical structure,converting ingested carotenoids into more oxidized and differently coloured forms(Schiedt,1998).
基金supported by a postdoctoral NERC research fellowship (NE/G013888/1)
文摘A strong focus of ecological research for several decades has been to understand the factors underlying the variation in animal life-histories. In recent times, ecological studies have begun to show that oxidative stress may represent another important modulator of competitive trade-offs among fitness traits or of positively integrated patterns of traits. Therefore, incorporating mechanisms underlying oxidative physiology into evolutionary ecology has the potential to help understand variation in life-history strategies. In this review, I provide a general overview of oxidative stress physiology, and subsequently focus on topics that have been neglected in previous ecological reviews on oxidative stress. Specifically, I introduce and discuss the adaptations that animals have evolved to cope with oxidative stress; the environmental stressors that can generate changes in oxidative balance; the role of reactive species in transduction of environmental stimuli and cell signaling; and the range of hormetic responses to oxidative stress [Current Zoology 56 （6）： 687-702, 2010].
文摘Oxidative stress is a key physiological mechanism underlying life-history tradeoffs. Here, I use meta-analytic techniques to test whether sexual differences in oxidative balance are common in vertebrates and to identify which factors are associated with such differences. The dataset included 732 effect size estimates from 100 articles （82 species）. Larger unsigned effect size （meaning larger sexual differences in a given marker） occurred in： reptiles and fish; those species that do not pro- vide parental care; and oviparous species. Estimates of signed effect size （positive values meaning higher oxidative stress in males） indicated that females were less resistant to oxidative stress than males in： reptiles while males and females were similar in fish, birds, and mammals; those species that do not provide parental care; and oviparous species. There was no evidence for a significant sexual differentiation in oxidative balance in fish, birds, and mammals. Effect size was not associ- ated with： the number of offspring; whether the experimental animals were reproducing or not; biomarker （oxidative damage, non-enzymatic, or enzymatic antioxidant）, the species body mass; the strain （wild vs. domestic）; or the study environment （wild vs. captivity）. Oxidative stress tended to be higher in females than males across most of the tissues analyzed. Levels of residual heterogeneity were high in all models tested. The findings of this meta-analysis indicate that diversification of reproductive strategies might be associated with sexual differences in oxidative balance. This explorative meta-analysis offers a starting platform for future research to investigate the rela-tionship between sex and oxidative balance further.
文摘Inbreeding negatively affects various life-history traits, with inbred individuals typically having lower fit- ness than outbred individuals （=inbreeding depression）. Inbreeding depression is often emphasized under environmental stress, but the underlying mechanisms and potential long-lasting consequences of such inbreeding-environment interactions remain poorly understood. Here, we hypothesize that inbreeding-environment interactions that occur early in life have long-term physiological effects, in partic- ular on the adult oxidative balance. We applied a unique experimental design to manipulate early life conditions of inbred and outbred songbirds （Serinus canaria） that allowed us to separate prenatal and postnatal components of early life conditions and their respective importance in inbreeding-environment interactions. We measured a wide variety of markers of oxidative status in adulthood, resulting in a com- prehensive account for oxidative balance. Using a Bayesian approach with Markov chain Monte Carlo, we found clear sex-specific effects and we also found only in females small yet significant long-term effects of inbreeding-environment interactions on adult oxidative balance. Postnatal components of early life conditions were most persuasively reflected on adult oxidative balance, with inbred females that experienced disadvantageous postnatal conditions upregulating enzymatic antioxidants in adulthood. Our study provides some evidence that adult oxidative balance can reflect inbreeding-environment inter- actions early in life, but given the rather small effects that were limited to females, we conclude that oxida- tive stress miaht have a limited role as mechanism underlvina inhre.e.dina-envirnnme.nt inte.raetinn.q_
基金supported by a grant from the Italian Ministry of Education,University and Research(PRIN project 2017KLZ3MA).
文摘Recent empirical and theoretical studies suggest that personality and locomotory performance traits linked to dispersal abilities are crucial components of the dispersal syndromes,and that they can evolve during range expansions and colonization processes.Island colonization is one of the best characterized processes in dispersal biogeography,and its implication in the evolution of phenotypic traits has been investigated over a wide range of temporal scales.However,the effect of island colonization on personality and performance traits of natural populations,and how these traits could drive island colonization,has been little explored.Noteworthy,no studies have addressed these processes in the context of late Pleistocene range expansions.Here,we investigated the contribution of island colonization triggered by postglacial range expansions to intraspecific variation in personality and locomotory performance traits.We compared boldness,exploration,jumping performance,and stickiness abilities in populations from 3 equidistant areas of the Tyrrhenian tree frog Hyla sarda,2 from the main island(Corsica Island),and 1 from the recently colonized island of Elba.Individuals from Elba were significantly bolder than individuals from Corsica,as they emerged sooner from a shelter(P=0.028),while individuals from Corsica showed markedly higher jumping and stickiness performance(both P<0.001),resulting as more performing than those of Elba.We discuss these results in the context of the major microevolutionary processes at play during range expansion,including selection,spatial sorting,founder effects,and their possible interaction with local adaptation processes.
文摘An increasing trend in use of tracking devices such as geolocators is based on the assumption that the information gathered from such devices provides reliable information about the migratory behavior of free-living birds. This underlying as- sumption is rarely tested, as evidenced by the absence in many studies of controls, in particular treated controls, and so far never with a reasonable statistical power. Published studies have shown reduced survival prospects or delayed breeding in some species, suggesting that there may be reason to doubt that tracking devices provide unbiased information. Therefore, we conducted a meta-analysis of studies applying geolocators to wild birds to determine whether geolocators affected fitness components. Ge- olocators had an overall negative effect on fitness components, in particular survival, and ecological variables. Effect size was larger for aerial foragers than for other species. Moreover the leg band attachment method was more detrimental for birds than the leg-loop backpack harness. A meta-regression model of effect size showed independent negative effects of geolocators on ae- rial foragers, smaller species, species with smaller migration distances and in studies where geolocators were attached with a ring. These results suggest that geolocator studies should be interpreted with caution, but also raise questions whether it is ethically defensible to use geolocators on aerial foragers or small species without carrying out robust pilot studies.
文摘Many animal species migrate over long distances, but the physiological challenges of migration are poorly understood. It has recently been suggested that increased molecular oxidative damage might be one important challenge for migratory animals. We tested the hypothesis that autumn migration imposes an oxidative challenge to bats by comparing values of 4 blood-based markers of oxidative status (oxidative damage and both enzymatic and nonenzymatic antioxidants) between Nathusius' bats Pipistrellus nathusii that were caught during migration flights with those measured in conspecifics after resting for 18 or 24 h. Experiments were carried out at Pape Ornithological Station in Pape (Latvia) in 2016 and 2017. Our results show that flying bats have a blood oxidative status different from that of resting bats due to higher oxidative damage and different expression of both non enzymatic and enzymatic antioxidants (glutathione peroxidase). The differences in oxidative status markers varied betwee n sampli ng years and were in depende nt from in dividual body con dition or sex. Our work provides evidence that migratory flight might impose acute oxidative stress to bats and that resting helps animals to recover from oxidative damage accrued en route. Our data suggest that migrating bats and birds might share similar strategies of mitigating and recovering from oxidative stress.
文摘Herpes viruses are responsible for a variety of pathological effects in humans and in both wild and domestic animals. One mechanism that has been proposed to facilitate replication and activity of herpes viruses is oxidative stress （OS）. We used meta-analytical techniques to test the hypotheses that （1） herpes virus infection causes OS and （2） supplementation of antioxidants reduces virus load, indicating that replication is favoured by a state of OS. Results based on studies on mammals, including humans, and birds show that （1） OS is indeed increased by herpes virus infection across multiple tissues and species, （2） biomarkers of OS may change differently between tissues, and （3） the effect size does not differ among different virus strains. In addition, the increase of oxidative damage in blood （tissue commonly available in ecological studies） was similar to that in the tissues most sensitive to the herpes virus. Our results also show that administration of antioxidants re- duces virus yield, indicating that a condition of OS is favorable for the viral replication. In addition, some antioxidants may be more efficient than others in reducing herpes virus yield. Our results point to a potential mechanism linking herpes virus infection to individual health status.
