Background: Acclimatization to winter conditions is an essential prerequisite for survival of small passerines of the northern temperate zone. In the present study, we measured diurnal variations in body mass, body te...Background: Acclimatization to winter conditions is an essential prerequisite for survival of small passerines of the northern temperate zone. In the present study, we measured diurnal variations in body mass, body temperature and basal metabolic rate(BMR) for seasonally acclimatized Hwameis(Garrulax canorus).Methods: Body mass was determined with a Sartorius balance. Metabolic rates of Hwameis were measured with an open-circuit respirometry system.Results: Body masses varied with time of day and were higher in daytime for Hwameis in both summer and winter, and body masses in winter were higher compared to that in summer. Body temperatures of Hwameis were higher in daytime, and the summer acclimatized birds had significantly higher body temperatures compared to the winter acclimatized birds. BMRs of Hwameis were significantly higher during the daytime compared to the nighttime of the daily cycle in both summer and winter, and Hwameis in winter had significantly higher BMRs than that in summer.Conclusions: This result showed that Hwameis rely mostly on metabolic capacity to maintain their body temperature in cold weathers, and Hwameis exhibited daily and seasonal flexibility in morphology and physiology which is important under changing environmental conditions.展开更多
The taxonomy of the Blue-crowned Laughingthrush(Garrulax courtoisi)and its relationship with the Yellowthroated Laughingthrush(G.galbanus)and G.c.simaoensis,a range-restricted subspecies in China,has not been fully el...The taxonomy of the Blue-crowned Laughingthrush(Garrulax courtoisi)and its relationship with the Yellowthroated Laughingthrush(G.galbanus)and G.c.simaoensis,a range-restricted subspecies in China,has not been fully elucidated.So the taxonomic status and system evolution of the three taxa G.courtoisi,G.galbanus and G.c.simaoensis need to be reclarified.Two gene sequences myoglobin(MYO)and the mitochondrial cytochrome coxidase subunit I(COI)were combined to investigate the phylogenetic relationships among courtoisi,simaoensis and galbanus,genetic data,combining with morphological,ecological and acoustic data were used to comb out the classification status and divergence level of the three taxa.Significant genetic and morphological differentiations(body size and plumage coloration)were detected between courtoisi and galbanus.However,no notable and reliable differences between the courtoisi and simaoensis were detected.The courtoisi,simaoensis and galbanus are clearly isolated in geographical distribution as a result of differing altitudes,climate conditions and habitats.The courtoisi has characteristic preference for nest location compared with galbanus.In addition,the results of song analysis also indicated that there are differences in maximum frequency between courtoisi and galbanus.G.courtoisi was confirmed to be an independent species based on genetic,morphological,geographical,ecological and vocal characteristics,and the validity of simaoensis as a subspecies still need more evidence.This study further confirmed the high conservation value of Blue-crowned Laughingthrush.In addition,due to the genetic differences between Simao and Wuyuan populations,this should be fully considered in future protection strategies.展开更多
基金financially supported by grants from the National Natural Science Foundation of China (No. 31070366 and 31470472)the Natural Science Foundation (LY13C030005) in Zhejiang Provincethe Zhejiang Province "Xinmiao" Project (2014R424032)
文摘Background: Acclimatization to winter conditions is an essential prerequisite for survival of small passerines of the northern temperate zone. In the present study, we measured diurnal variations in body mass, body temperature and basal metabolic rate(BMR) for seasonally acclimatized Hwameis(Garrulax canorus).Methods: Body mass was determined with a Sartorius balance. Metabolic rates of Hwameis were measured with an open-circuit respirometry system.Results: Body masses varied with time of day and were higher in daytime for Hwameis in both summer and winter, and body masses in winter were higher compared to that in summer. Body temperatures of Hwameis were higher in daytime, and the summer acclimatized birds had significantly higher body temperatures compared to the winter acclimatized birds. BMRs of Hwameis were significantly higher during the daytime compared to the nighttime of the daily cycle in both summer and winter, and Hwameis in winter had significantly higher BMRs than that in summer.Conclusions: This result showed that Hwameis rely mostly on metabolic capacity to maintain their body temperature in cold weathers, and Hwameis exhibited daily and seasonal flexibility in morphology and physiology which is important under changing environmental conditions.
基金supported by the National Natural Science Foundation of China(No.31660608,31360521)。
文摘The taxonomy of the Blue-crowned Laughingthrush(Garrulax courtoisi)and its relationship with the Yellowthroated Laughingthrush(G.galbanus)and G.c.simaoensis,a range-restricted subspecies in China,has not been fully elucidated.So the taxonomic status and system evolution of the three taxa G.courtoisi,G.galbanus and G.c.simaoensis need to be reclarified.Two gene sequences myoglobin(MYO)and the mitochondrial cytochrome coxidase subunit I(COI)were combined to investigate the phylogenetic relationships among courtoisi,simaoensis and galbanus,genetic data,combining with morphological,ecological and acoustic data were used to comb out the classification status and divergence level of the three taxa.Significant genetic and morphological differentiations(body size and plumage coloration)were detected between courtoisi and galbanus.However,no notable and reliable differences between the courtoisi and simaoensis were detected.The courtoisi,simaoensis and galbanus are clearly isolated in geographical distribution as a result of differing altitudes,climate conditions and habitats.The courtoisi has characteristic preference for nest location compared with galbanus.In addition,the results of song analysis also indicated that there are differences in maximum frequency between courtoisi and galbanus.G.courtoisi was confirmed to be an independent species based on genetic,morphological,geographical,ecological and vocal characteristics,and the validity of simaoensis as a subspecies still need more evidence.This study further confirmed the high conservation value of Blue-crowned Laughingthrush.In addition,due to the genetic differences between Simao and Wuyuan populations,this should be fully considered in future protection strategies.
