Color polymorphisms are widely studied to identify the mechanisms responsible for the origin and maintenance of phenotypic variability in nature.Two of the mechanisms of balancing selection currently thought to explai...Color polymorphisms are widely studied to identify the mechanisms responsible for the origin and maintenance of phenotypic variability in nature.Two of the mechanisms of balancing selection currently thought to explain the long-term persistence of polymorphisms are the evolution of alternative phenotypic optima through correlational selection on suites of traits including color and heterosis.Both of these mechanisms can generate differences in offspring viability and fitness arising from different morph combinations.Here,we examined the effect of parental morph combination on fertilization success,embryonic viability,newborn quality,antipredator,and foraging behavior,as well as inter-annual survival by conducting controlled matings in a polymorphic lacertid Podarcis muralis,where color morphs are frequently assumed to reflect alternative phenotypic optima(e.g.,alternative reproductive strategies).Juveniles were kept in outdoor tubs for a year in order to study inter-annual growth,survival,and morph inheritance.In agreement with a previous genome-wide association analysis,morph frequencies in the year-old juveniles matched the frequencies expected if orange and yellow expressions depended on recessive homozygosity at 2 separate loci.Our findings also agree with previous literature reporting higher reproductive output of heavy females and the higher overall viability of heavy newborn lizards,but we found no evidence for the existence of alternative breeding investment strategies in female morphs,or morphcombination effects on offspring viability and behavior.We conclude that inter-morph breeding remains entirely viable and genetic incompatibilities are of little significance for the maintenance of discrete color morphs in P.muralis from the Pyrenees.展开更多
Climate change is generating range shifts in many organisms,notably along the elevational gradient in mountainous environments.However,moving up in elevation exposes organisms to lower oxygen availability,which may re...Climate change is generating range shifts in many organisms,notably along the elevational gradient in mountainous environments.However,moving up in elevation exposes organisms to lower oxygen availability,which may reduce the successful reproduction and development of oviparous organisms.To test this possibility in an upwardcolonizing species,we artificially incubated developing embryos of the viperine snake(Natrix maura)using a split-clutch design,in conditions of extreme high elevation(hypoxia at 2877 m above sea level;72%sea-level equivalent O2 availability)or low elevation(control group;i.e.normoxia at 436 m above sea level).Hatching success did not differ between the two treatments.Embryos developing at extreme high elevation had higher heart rates and hatched earlier,resulting in hatchlings that were smaller in body size and slower swimmers compared to their siblings incubated at lower elevation.Furthermore,post-hatching reciprocal transplant of juveniles showed that snakes which developed at extreme high elevation,when transferred back to low elevation,did not recover full performance compared to their siblings from the low elevation incubation treatment.These results suggest that incubation at extreme high elevation,including the effects of hypoxia,will not prevent oviparous ectotherms from producing viable young,but may pose significant physiological challenges on developing offspring in ovo.These early-life performance limitations imposed by extreme high elevation could have negative consequences on adult phenotypes,including on fitness-related traits.展开更多
基金The study was supported in part by grant PID2019-104721GB-I00 of the Spanish Ministerio de Ciencia e Innovacion to EF and GPL and from the University of Valencia(UV-19-INV-AE19)FEDER through the COMPETE program(ref.008929)+7 种基金the Swedish Research Council(2017-03846)the Knut and Alice Wallenberg Foundation(Wallenberg Academy fellowship to T.U.),Portuguese national funds through the FCT project PTDC/BIA-EVL/30288/2017-NORTE-01-0145-FEDER-30288co-funded by NORTE2020 through Portugal 2020 and FEDER Funds and by National Funds through FCTby the Laboratoire d’Excellence(LABEX)TULIP(ANR-10-LABX-41)and the INTERREG POCTEFA ECTOPYR(EFA031/15)This work has also benefitted from state aid managed by the French national research agency under the Future Investments program bearing the reference ANR-11-INBS-0001AnaEE-ServicesLizards were captured under research permits number 2013095-0001 from the Prefecture des Pyrenees-Orientales,and permit numbers 2016-s-09 and 2017-s-02 from the Prefecture des Pyrenees-Orientales and the Prefecture de l’Ariege(Direction Regionale de l’Environnement,de l’Amenagement,et du Logement,Occitanie)This research complied with the ASAB/ABS Guidelines for the Use of Animals in Research and all applicable local,national,and European legislation.J.A.was supported by a FPU predoctoral fellowship from the Spanish Ministerio de Educacion(FPU15/01388).G.P.L.was supported by post-doctoral grants Juan de la Cierva-Incorporacion,IJC2018-035319-I(from the Spanish Ministerio de Ciencia,Inovacio n y Universidades)grant SFRH/BPD/94582/2013 by Fundacao para a Ciencia e a Tecnologia under the Programa Operacional Potencial Humano–Quadro de Referencia Estrategico Nacional,funds from the European Social Fund and Portuguese Ministerio da Educac¸~ao e Cieˆncia.
文摘Color polymorphisms are widely studied to identify the mechanisms responsible for the origin and maintenance of phenotypic variability in nature.Two of the mechanisms of balancing selection currently thought to explain the long-term persistence of polymorphisms are the evolution of alternative phenotypic optima through correlational selection on suites of traits including color and heterosis.Both of these mechanisms can generate differences in offspring viability and fitness arising from different morph combinations.Here,we examined the effect of parental morph combination on fertilization success,embryonic viability,newborn quality,antipredator,and foraging behavior,as well as inter-annual survival by conducting controlled matings in a polymorphic lacertid Podarcis muralis,where color morphs are frequently assumed to reflect alternative phenotypic optima(e.g.,alternative reproductive strategies).Juveniles were kept in outdoor tubs for a year in order to study inter-annual growth,survival,and morph inheritance.In agreement with a previous genome-wide association analysis,morph frequencies in the year-old juveniles matched the frequencies expected if orange and yellow expressions depended on recessive homozygosity at 2 separate loci.Our findings also agree with previous literature reporting higher reproductive output of heavy females and the higher overall viability of heavy newborn lizards,but we found no evidence for the existence of alternative breeding investment strategies in female morphs,or morphcombination effects on offspring viability and behavior.We conclude that inter-morph breeding remains entirely viable and genetic incompatibilities are of little significance for the maintenance of discrete color morphs in P.muralis from the Pyrenees.
基金the French Laboratory of Excellence project“TULIP”(ANR-10-LABX-41,ANR-11-IDEX-0002-02)INTERREG POCTEFA ECTOPYR(no.EFA031/15)+2 种基金the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 752299All experimental protocols(including animal collection,housing,experimentation,and release)were approved by the DREAL Midi-Pyrénées(Direction Régionale de l’Environnement,de l’Aménagement et du Logement)and by the Préfectures of Ariège,Aude,Haute-Garonne,Hautes-Pyrénées,and Pyrénées Orientales districts(ArrêtéPréfectoral No.2017-s-02 du 30 mars 2017)and ethical committee(APAFIS#16359-201808011445465 v4)All experiments were carried out in accordance with the approved guidelines.Animal caretakers and handlers were trained to use wildlife in scientific purposes(Decree No.2013-118 du 01 février 2013 and approval of the Ministry of Agriculture under No.I-75-MNHN-F1-15 du 17 juin 2015).
文摘Climate change is generating range shifts in many organisms,notably along the elevational gradient in mountainous environments.However,moving up in elevation exposes organisms to lower oxygen availability,which may reduce the successful reproduction and development of oviparous organisms.To test this possibility in an upwardcolonizing species,we artificially incubated developing embryos of the viperine snake(Natrix maura)using a split-clutch design,in conditions of extreme high elevation(hypoxia at 2877 m above sea level;72%sea-level equivalent O2 availability)or low elevation(control group;i.e.normoxia at 436 m above sea level).Hatching success did not differ between the two treatments.Embryos developing at extreme high elevation had higher heart rates and hatched earlier,resulting in hatchlings that were smaller in body size and slower swimmers compared to their siblings incubated at lower elevation.Furthermore,post-hatching reciprocal transplant of juveniles showed that snakes which developed at extreme high elevation,when transferred back to low elevation,did not recover full performance compared to their siblings from the low elevation incubation treatment.These results suggest that incubation at extreme high elevation,including the effects of hypoxia,will not prevent oviparous ectotherms from producing viable young,but may pose significant physiological challenges on developing offspring in ovo.These early-life performance limitations imposed by extreme high elevation could have negative consequences on adult phenotypes,including on fitness-related traits.
