Non-signaling functions of coloration include thermoregulation(thermal melanism hypothesis),protection against ultraviolet radiation(photoprotection hypothesis),and concealment from predators(crypsis hypothesis).We in...Non-signaling functions of coloration include thermoregulation(thermal melanism hypothesis),protection against ultraviolet radiation(photoprotection hypothesis),and concealment from predators(crypsis hypothesis).We investigated whether dorsal coloration in 19 populations of spiny-footed lizards,Acanthodactylus erythrurus,across the Iberian Peninsula varies according to these functions.We captured adult males and females in each population and calculated standardized dorsum brightness estimates from photographs.We also calculated standardized ground luminosity estimates and gathered information on latitude,altitude,mean annual temperature,and mean annual solar radiation for each location.Males showed a higher percentage of black coloration and a more contrasted dorsum than females,suggesting different selection pressures on dorsal coloration in both sexes.Furthermore,males showed a darker dorsum and a higher percentage of black coloration at higher altitudes and when the ground was darker.In contrast,females exhibited a darker dorsum only when the ground was darker and a higher percentage of black coloration only at higher altitudes.We also observed that the variation of dorsum luminosity within males and the variation of dorsum luminosity among females within populations were both positively related to the variation of ground luminosity among different points within locations.Latitude,temperature,and solar radiation were not signifcantly related to dorsal coloration in either sex.Our results support the photoprotection and crypsis hypotheses in males and,to some extent,in females,whereas the thermal melanism hypothesis is weakly supported in both sexes.These fndings suggest that there is local adaptation in the dorsal coloration of the spiny-footed lizard.展开更多
Freshwater ecosystems are crucial in the global emissions of greenhouse gases(GHGs)such as CH_(4).Macrophytes are the main organic matter(i.e.,detritus)supplier to the sediment of these systems,thus controlling CH_(4)...Freshwater ecosystems are crucial in the global emissions of greenhouse gases(GHGs)such as CH_(4).Macrophytes are the main organic matter(i.e.,detritus)supplier to the sediment of these systems,thus controlling CH_(4) production.However,species-specific differences(structure and composition)may determine contrasting patterns of detritus transformation into CH_(4).Furthermore,eutrophication can affect the degradation and,consequently,CH_(4) production.We performed a 64-day microcosm experiment with anoxic incubations of detritus from seven phylogenetically different macrophytes(two charophytes,filamentous algae–Spirogyra,Cladophora–,three submerged plants and an amphibious one),under two trophic conditions(oligo-versus eutrophic)and with/without sediment.We assessed the CH_(4) and CO_(2) production and the changes in the detritus quality at the end of the experiment.The ranking in the mean cumulative CH_(4) production was:Chara hispida>Nitella hyalina>Najasmarina≈Teucrium scordium>Stuckenia pectinata≈Myriophyllum spicatum>filamentous algae,and it was related to the detritus quality.GHGs maximumproduction rates were 1.6(N.marina)-1.2(C.hispida)mmol CH_(4)/(g OC·day)and 1.7(N.marina)-1.5(C.hispida)mmol CO_(2)/(g OC·day).The CO_(2):CH_(4) ratiowas biased towards CO_(2) during the first 10 days(average ratio of 200)and fell afterwards to about 1 for all macrophyte species and treatments.The sediment favored detritus decomposition(probably due to the“positive priming effect”),increasing GHGs production.The influence of nutrient enrichment was not evident.Delving into themacrophyte detritus quality-GHGs production relationship is needed to forecast the GHGs emissions in macrophyte-dominated systems.展开更多
In China,flash floods are one of the main natural disasters causing loss of life and damage to infrastructure.The threat of flash floods is exacerbated with climate change and increased human activities,such that the ...In China,flash floods are one of the main natural disasters causing loss of life and damage to infrastructure.The threat of flash floods is exacerbated with climate change and increased human activities,such that the number of disasters has shown a clear upward trend in recent years.However,due to the scarcity of instrumental data or overly short timeseries,we are still lacking critical data to understand spatio-temporal patterns and driving factors of extreme flash floods.This missing knowledge is however crucial for a proper management of these hazards,especially in remote mountain environments.In forested catchments,dendrogeomorphology allows the reconstruction of past process activity based on growth disturbances(GDs)in trees that have been affected by past flash floods.Therefore,in our study,for the first time,we reconstruct past flash floods in the Qilian Mountains,northeast Tibetan Plateau,over past centuries.To this end,we sampled 99 Qinghai spruce(Picea crassifolia)trees affected by flash floods,with a total of 194increment cores,and identified 302 GDs induced by past flash floods.These GDs have been caused by at least 21 flash floods that we are able to reconstruct over the last 170 years.The position of GDs within tree rings and the intra-seasonal dating of past events also allowed discussion of the likely synoptic situations that may have led to the triggering of flash floods in the past.Logistic regression analysis confirms that significant correlation exists between cumulative maximum 5-day August-September precipitation and reconstructed flash floods,which is corresponding to the majority of scars and related tangential rows of traumatic resin ducts(TRDs)found in the latewood portion of growth rings.These results support the idea that abundant precipitation occurring at the end of the summer season and early fall is the key factor driving flash floods in our study area.Our research not only fills the gaps regarding historical flash flood histories in the Qilian Mountains,but also provides a scientific basis for the region's response to climate change and flood prevention and reduction.展开更多
Genetic characterization of species using phylogeographic approaches represents a basic reference to understand their evolutionary history as well as to identify conservation priorities to protect areas of particular ...Genetic characterization of species using phylogeographic approaches represents a basic reference to understand their evolutionary history as well as to identify conservation priorities to protect areas of particular interest regarding evolutionary potential.Even in well-studied regions such information is lacking for the majority of species,including many endemic species with reduced distribution ranges.We investigate the phylogeographic pattern of the Iberian frog Rana iberica,an endemic amphibian restricted to Central and North-Western Iberian Peninsula.Using mitochondrial sequences,we reconstruct the phylogeographic history of the species to test the effect of Quaternary climate changes on the evolutionary diversification of lineages,that is,the differentiation of mitochondrial lineages and the formation of genetic diversity melting pots,and integrate phylogeographic evidence for future conservation planning.Our results indicate the existence of 3 main mitochondrial lineages differentiated during the Upper Pleistocene.Both historical demographic analyses and climatic niche modeling show a strong effect of glacial climate changes,suggesting recurrent range contractions and expansions.Under such circumstances,differentiation took place most likely by isolation in allopatric interglacial refugia.Secondary lineage admixture in northern Portugal generated a broad mixed zone with highest nucleotide diversity.Given its particular evolutionary potential,its reduced distribution and eventual threats under current climate change scenario,conservation priorities should focus on the isolated lineage from Sierra de Guadalupe.展开更多
Studies on the impacts of variation of biotic interactions at key life cycle stages are crucial to understand the interface between ecological and developmental processes.Predators exert a major impact on prey fitness...Studies on the impacts of variation of biotic interactions at key life cycle stages are crucial to understand the interface between ecological and developmental processes.Predators exert a major impact on prey fitness.Although direct consumption entails the greatest effect,predators can affect prey by means of other mechanisms.For instance,injuries inflicted by failed predation attempts can jeopardize prey fitness,even beyond the short-term.In anuran tadpoles,failed predation typically results in partial tail loss,which is known to reduce swimming speed.However,the potential consequences of tadpole partial tail loss after metamorphosis remain understudied.Because tail materials could be important in conforming metamorph body,we assess the effects of tadpole partial tail loss on metamorph body size in Iberian spadefoot toads Pelobates cultripes.We clipped 55%tail length of pre-tail-resorption stage anesthetized tadpoles,and compared their body size as metamorphs with anesthetized and non-anesthetized non-tail-clipped controls.Also,we tested whether tail length correlated with metamorph body size of individuals of the control groups.Tailclipped tadpoles produced smaller metamorphs than both controls(the bdy size of metamorphs from both controls was similar),which could incur costs in mid-term survival or time to first reproduction.This effect could be particularly important in areas with introduced predators,if autochthonous tadpoles lack defenses against them.Results suggest that materials resorbed from tadpole tail tissues might be reallocated into metamorph body,according to the negative effect of shorter tails in a correlational analysis,and clipped tails in an experimental test,on metamorph body size.展开更多
Anostraca are known by their ability for long-distance dispersal,but the existence in several species of deep,geographically structured mtDNA lineages suggests their populations are subjected to allopatric differentia...Anostraca are known by their ability for long-distance dispersal,but the existence in several species of deep,geographically structured mtDNA lineages suggests their populations are subjected to allopatric differentiation,isolation,and prevalence of local scale dispersion.Tanymastix stagnalis is one of the most widespread species of Anostraca and previous studies revealed an unclear geographical pattern of mtDNA genetic diversity.Here,we analyze populations from the Iberian and Italian Peninsulas,Central Europe,and Scandinavia,with the aim to characterize the patterns of genetic diversity in a spatio-temporal framework using mtDNA and nuclear markers to test gene flow among close populations.For these aims we built a time-calibrated phylogeny and carried out Bayesian phylogeographic analyses using a continuous diffusion model.Our results indicated that T.stagnalis presents a deeply structured genetic diversity,including 7 ancient lineages,some of them even predating the Pleistocene.The Iberian Peninsula harbors high diversity of lineages,with strong isolation and recent absence of gene flow between populations.Dispersal at local scale seems to be the prevailing dispersal mode of T.stagnalis,which exhibits a pattern of isolation-bydistance in the Iberian Peninsula.We remark the vulnerability of most of these lineages,given the limited known geographic distribution of some of them,and the high risk of losing important evolutionary potential for the species.展开更多
The thermoluminescence(TL)emission of synthetic and natural Ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view tryi...The thermoluminescence(TL)emission of synthetic and natural Ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view trying to link each TL peak to a chemical-physical process.The kinetic parameters that lead the luminescence processes were calculated by means of variable heating rate and computing glow curve deconvolution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic CePO_(4):Nd_(0.20),La_(0.25)).The main differences appreciated in these complex TL curves are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence mechanism.Each peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,Ce3+?Ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,Frenkel defects,ODCs or NBOHCs).展开更多
The study of host–parasite co-evolution is a central topic in evolutionary ecology.However,research is still fragmented and the extent to which parasites influence host life history is debated.One reason for this inc...The study of host–parasite co-evolution is a central topic in evolutionary ecology.However,research is still fragmented and the extent to which parasites influence host life history is debated.One reason for this incomplete picture is the frequent omission of environmental conditions in studies analyzing host–parasite dynamics,which may influence the exposure to or effects of parasitism.To contribute to elucidating the largely unresolved question of how environmental conditions are related to the prevalence and intensity of infestation and their impact on hosts,we took advantage of 25 years of monitoring of a breeding population of pied flycatchers,Ficedula hypoleuca,in a Mediterranean area of central Spain.We investigated the influence of temperature and precipitation during the nestling stage at a local scale on the intensity of blowfly(Protocalliphora azurea)parasitism during the nestling stage.In addition,we explored the mediating effect of extrinsic and intrinsic factors and blowfly parasitism on breeding success(production of fledglings)and offspring quality(nestling mass on day 13).The prevalence and intensity of blowfly parasitism were associated with different intrinsic(host breeding date,brood size)and extrinsic(breeding habitat,mean temperature)factors.Specifically,higher average temperatures during the nestling phase were associated with lower intensities of parasitism,which may be explained by changes in blowflies’activity or larval developmental success.In contrast,no relationship was found between the prevalence of parasitism and any of the environmental variables evaluated.Hosts that experienced high parasitism intensities in their broods produced more fledglings as temperature increased,suggesting that physiological responses to severe parasitism during nestling development might be enhanced in warmer conditions.The weight of fledglings was,however,unrelated to the interactive effect of parasitism intensity and environmental conditions.Overall,our results highlight the temperature dependence of parasite–host interactions and the importance of considering multiple fitness indicators and climate-mediated effects to understand their complex implications for avian fitness and population dynamics.展开更多
INTRODUCTION Evolution of behavioral responses is often dependent on the existence of modified structures that enable the development of the behavioral suite(Kay 1978;Lundrigan 1996;Alfaro et al.2004;Goyens et al.2015...INTRODUCTION Evolution of behavioral responses is often dependent on the existence of modified structures that enable the development of the behavioral suite(Kay 1978;Lundrigan 1996;Alfaro et al.2004;Goyens et al.2015;Higham et al.2015;Sharp et al.2018;Schendel et al.2019).Occasionally,structural modifications are so important that a direct link between morphology and behavior can be inferred(Fleagle 1977;Rodman 1979;Losos 1990a;Higham et al.2015).展开更多
基金funded by the European Regional Development Fund(ERDF A way of making Europe)and the Spanish Ministry of Education and Science(grant CGL2008-00137/BOS).
文摘Non-signaling functions of coloration include thermoregulation(thermal melanism hypothesis),protection against ultraviolet radiation(photoprotection hypothesis),and concealment from predators(crypsis hypothesis).We investigated whether dorsal coloration in 19 populations of spiny-footed lizards,Acanthodactylus erythrurus,across the Iberian Peninsula varies according to these functions.We captured adult males and females in each population and calculated standardized dorsum brightness estimates from photographs.We also calculated standardized ground luminosity estimates and gathered information on latitude,altitude,mean annual temperature,and mean annual solar radiation for each location.Males showed a higher percentage of black coloration and a more contrasted dorsum than females,suggesting different selection pressures on dorsal coloration in both sexes.Furthermore,males showed a darker dorsum and a higher percentage of black coloration at higher altitudes and when the ground was darker.In contrast,females exhibited a darker dorsum only when the ground was darker and a higher percentage of black coloration only at higher altitudes.We also observed that the variation of dorsum luminosity within males and the variation of dorsum luminosity among females within populations were both positively related to the variation of ground luminosity among different points within locations.Latitude,temperature,and solar radiation were not signifcantly related to dorsal coloration in either sex.Our results support the photoprotection and crypsis hypotheses in males and,to some extent,in females,whereas the thermal melanism hypothesis is weakly supported in both sexes.These fndings suggest that there is local adaptation in the dorsal coloration of the spiny-footed lizard.
基金supported by Spanish Ministry of Science and Innovation (No.PID2020–116147GB-C22)funded by the European Union (Next Generation UE)+1 种基金funded by the Programa de Posgrado en Ciencias del Mar y Limnología (UNAM)CONAHCYT (CVU:828722).
文摘Freshwater ecosystems are crucial in the global emissions of greenhouse gases(GHGs)such as CH_(4).Macrophytes are the main organic matter(i.e.,detritus)supplier to the sediment of these systems,thus controlling CH_(4) production.However,species-specific differences(structure and composition)may determine contrasting patterns of detritus transformation into CH_(4).Furthermore,eutrophication can affect the degradation and,consequently,CH_(4) production.We performed a 64-day microcosm experiment with anoxic incubations of detritus from seven phylogenetically different macrophytes(two charophytes,filamentous algae–Spirogyra,Cladophora–,three submerged plants and an amphibious one),under two trophic conditions(oligo-versus eutrophic)and with/without sediment.We assessed the CH_(4) and CO_(2) production and the changes in the detritus quality at the end of the experiment.The ranking in the mean cumulative CH_(4) production was:Chara hispida>Nitella hyalina>Najasmarina≈Teucrium scordium>Stuckenia pectinata≈Myriophyllum spicatum>filamentous algae,and it was related to the detritus quality.GHGs maximumproduction rates were 1.6(N.marina)-1.2(C.hispida)mmol CH_(4)/(g OC·day)and 1.7(N.marina)-1.5(C.hispida)mmol CO_(2)/(g OC·day).The CO_(2):CH_(4) ratiowas biased towards CO_(2) during the first 10 days(average ratio of 200)and fell afterwards to about 1 for all macrophyte species and treatments.The sediment favored detritus decomposition(probably due to the“positive priming effect”),increasing GHGs production.The influence of nutrient enrichment was not evident.Delving into themacrophyte detritus quality-GHGs production relationship is needed to forecast the GHGs emissions in macrophyte-dominated systems.
基金supported by the National Natural Science Foundation of China[Grant No.41977392]the National Key R&D Program of China[Grant No.2019YFA0606602]+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA20090000)Qilian Mountain National Park Qinghai Province management bureaufinanced by the China Scholarship Council。
文摘In China,flash floods are one of the main natural disasters causing loss of life and damage to infrastructure.The threat of flash floods is exacerbated with climate change and increased human activities,such that the number of disasters has shown a clear upward trend in recent years.However,due to the scarcity of instrumental data or overly short timeseries,we are still lacking critical data to understand spatio-temporal patterns and driving factors of extreme flash floods.This missing knowledge is however crucial for a proper management of these hazards,especially in remote mountain environments.In forested catchments,dendrogeomorphology allows the reconstruction of past process activity based on growth disturbances(GDs)in trees that have been affected by past flash floods.Therefore,in our study,for the first time,we reconstruct past flash floods in the Qilian Mountains,northeast Tibetan Plateau,over past centuries.To this end,we sampled 99 Qinghai spruce(Picea crassifolia)trees affected by flash floods,with a total of 194increment cores,and identified 302 GDs induced by past flash floods.These GDs have been caused by at least 21 flash floods that we are able to reconstruct over the last 170 years.The position of GDs within tree rings and the intra-seasonal dating of past events also allowed discussion of the likely synoptic situations that may have led to the triggering of flash floods in the past.Logistic regression analysis confirms that significant correlation exists between cumulative maximum 5-day August-September precipitation and reconstructed flash floods,which is corresponding to the majority of scars and related tangential rows of traumatic resin ducts(TRDs)found in the latewood portion of growth rings.These results support the idea that abundant precipitation occurring at the end of the summer season and early fall is the key factor driving flash floods in our study area.Our research not only fills the gaps regarding historical flash flood histories in the Qilian Mountains,but also provides a scientific basis for the region's response to climate change and flood prevention and reduction.
文摘Genetic characterization of species using phylogeographic approaches represents a basic reference to understand their evolutionary history as well as to identify conservation priorities to protect areas of particular interest regarding evolutionary potential.Even in well-studied regions such information is lacking for the majority of species,including many endemic species with reduced distribution ranges.We investigate the phylogeographic pattern of the Iberian frog Rana iberica,an endemic amphibian restricted to Central and North-Western Iberian Peninsula.Using mitochondrial sequences,we reconstruct the phylogeographic history of the species to test the effect of Quaternary climate changes on the evolutionary diversification of lineages,that is,the differentiation of mitochondrial lineages and the formation of genetic diversity melting pots,and integrate phylogeographic evidence for future conservation planning.Our results indicate the existence of 3 main mitochondrial lineages differentiated during the Upper Pleistocene.Both historical demographic analyses and climatic niche modeling show a strong effect of glacial climate changes,suggesting recurrent range contractions and expansions.Under such circumstances,differentiation took place most likely by isolation in allopatric interglacial refugia.Secondary lineage admixture in northern Portugal generated a broad mixed zone with highest nucleotide diversity.Given its particular evolutionary potential,its reduced distribution and eventual threats under current climate change scenario,conservation priorities should focus on the isolated lineage from Sierra de Guadalupe.
文摘Studies on the impacts of variation of biotic interactions at key life cycle stages are crucial to understand the interface between ecological and developmental processes.Predators exert a major impact on prey fitness.Although direct consumption entails the greatest effect,predators can affect prey by means of other mechanisms.For instance,injuries inflicted by failed predation attempts can jeopardize prey fitness,even beyond the short-term.In anuran tadpoles,failed predation typically results in partial tail loss,which is known to reduce swimming speed.However,the potential consequences of tadpole partial tail loss after metamorphosis remain understudied.Because tail materials could be important in conforming metamorph body,we assess the effects of tadpole partial tail loss on metamorph body size in Iberian spadefoot toads Pelobates cultripes.We clipped 55%tail length of pre-tail-resorption stage anesthetized tadpoles,and compared their body size as metamorphs with anesthetized and non-anesthetized non-tail-clipped controls.Also,we tested whether tail length correlated with metamorph body size of individuals of the control groups.Tailclipped tadpoles produced smaller metamorphs than both controls(the bdy size of metamorphs from both controls was similar),which could incur costs in mid-term survival or time to first reproduction.This effect could be particularly important in areas with introduced predators,if autochthonous tadpoles lack defenses against them.Results suggest that materials resorbed from tadpole tail tissues might be reallocated into metamorph body,according to the negative effect of shorter tails in a correlational analysis,and clipped tails in an experimental test,on metamorph body size.
基金the Project Grant CGL2015-66571-P(MINECO/FEDER)of Spain.
文摘Anostraca are known by their ability for long-distance dispersal,but the existence in several species of deep,geographically structured mtDNA lineages suggests their populations are subjected to allopatric differentiation,isolation,and prevalence of local scale dispersion.Tanymastix stagnalis is one of the most widespread species of Anostraca and previous studies revealed an unclear geographical pattern of mtDNA genetic diversity.Here,we analyze populations from the Iberian and Italian Peninsulas,Central Europe,and Scandinavia,with the aim to characterize the patterns of genetic diversity in a spatio-temporal framework using mtDNA and nuclear markers to test gene flow among close populations.For these aims we built a time-calibrated phylogeny and carried out Bayesian phylogeographic analyses using a continuous diffusion model.Our results indicated that T.stagnalis presents a deeply structured genetic diversity,including 7 ancient lineages,some of them even predating the Pleistocene.The Iberian Peninsula harbors high diversity of lineages,with strong isolation and recent absence of gene flow between populations.Dispersal at local scale seems to be the prevailing dispersal mode of T.stagnalis,which exhibits a pattern of isolation-bydistance in the Iberian Peninsula.We remark the vulnerability of most of these lineages,given the limited known geographic distribution of some of them,and the high risk of losing important evolutionary potential for the species.
文摘The thermoluminescence(TL)emission of synthetic and natural Ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view trying to link each TL peak to a chemical-physical process.The kinetic parameters that lead the luminescence processes were calculated by means of variable heating rate and computing glow curve deconvolution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic CePO_(4):Nd_(0.20),La_(0.25)).The main differences appreciated in these complex TL curves are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence mechanism.Each peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,Ce3+?Ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,Frenkel defects,ODCs or NBOHCs).
基金support from projects CGL2006-07481/BOS(to J.C.Senar),CGL2009-10652(to J.C.Senar),CGL2011-29694(to J.Potti),and CGL2014-55969-P(to F.Valera)from the Spanish Ministry of Educationwell as project PAC05-006-2(to J.A.Dávila)from the Universidad de Castilla-La Mancha(Spain)+6 种基金During the writing process,E.G.B.was supported by a Margarita Salas Contract financed by the European Union-NextGenerationEU and the Recovery,Transformation,and Resilience Plan(Spanish Ministry of Universities)D.C.received support through a Talent Attraction fellowship from the Autonomous Community of Madrid(CAM),Spain(2022-T1_AMB-24025)the projects PID2022-141763NA-I00,CGL2015-70639-P,and PID2019-104835GB-I00funded by MCIN/AEI(doi:10.13039/501100011033)C.C.was supported by the grant ref.RYC2021-033977-I funded by MCIN/AEI/10.13039/501100011033the European Union NextGeneration EU/PRTR.J.M.P.was supported by the ARAID FoundationFunding for open access charge:Universidad de Granada/CBUA.
文摘The study of host–parasite co-evolution is a central topic in evolutionary ecology.However,research is still fragmented and the extent to which parasites influence host life history is debated.One reason for this incomplete picture is the frequent omission of environmental conditions in studies analyzing host–parasite dynamics,which may influence the exposure to or effects of parasitism.To contribute to elucidating the largely unresolved question of how environmental conditions are related to the prevalence and intensity of infestation and their impact on hosts,we took advantage of 25 years of monitoring of a breeding population of pied flycatchers,Ficedula hypoleuca,in a Mediterranean area of central Spain.We investigated the influence of temperature and precipitation during the nestling stage at a local scale on the intensity of blowfly(Protocalliphora azurea)parasitism during the nestling stage.In addition,we explored the mediating effect of extrinsic and intrinsic factors and blowfly parasitism on breeding success(production of fledglings)and offspring quality(nestling mass on day 13).The prevalence and intensity of blowfly parasitism were associated with different intrinsic(host breeding date,brood size)and extrinsic(breeding habitat,mean temperature)factors.Specifically,higher average temperatures during the nestling phase were associated with lower intensities of parasitism,which may be explained by changes in blowflies’activity or larval developmental success.In contrast,no relationship was found between the prevalence of parasitism and any of the environmental variables evaluated.Hosts that experienced high parasitism intensities in their broods produced more fledglings as temperature increased,suggesting that physiological responses to severe parasitism during nestling development might be enhanced in warmer conditions.The weight of fledglings was,however,unrelated to the interactive effect of parasitism intensity and environmental conditions.Overall,our results highlight the temperature dependence of parasite–host interactions and the importance of considering multiple fitness indicators and climate-mediated effects to understand their complex implications for avian fitness and population dynamics.
基金This study was funded by the Spanish government MCIN/AEI/10.13039/501100011033/and FEDER“A way to make Europe,”through the project PID2019-110243GB-I00 to MGP.E.K.L.-E.was supported by a doctoral scholarship from CONACyT-Mexico(330519/472100).
文摘INTRODUCTION Evolution of behavioral responses is often dependent on the existence of modified structures that enable the development of the behavioral suite(Kay 1978;Lundrigan 1996;Alfaro et al.2004;Goyens et al.2015;Higham et al.2015;Sharp et al.2018;Schendel et al.2019).Occasionally,structural modifications are so important that a direct link between morphology and behavior can be inferred(Fleagle 1977;Rodman 1979;Losos 1990a;Higham et al.2015).
