Males of Platycnemis latipes (Platycnemididae, Odonata) have enlarged tibiae (fans) and patrol using a special longitudinal zig-zag flight. By means of focal observations and experimental manipulations of the colour o...Males of Platycnemis latipes (Platycnemididae, Odonata) have enlarged tibiae (fans) and patrol using a special longitudinal zig-zag flight. By means of focal observations and experimental manipulations of the colour of abdomen and fans of mature males, we suggest that the zig-zag flight is used to avoid unnecessary harassment from other males and has not the function to attract females. The fans of P. latipes are mainly used as a tool to threaten rivals, but their effectiveness seems limited. Both abdomen and fans of a mature male can reflect UV light strongly.展开更多
Reflection of ultraviolet （UV） light by the wings of the female Eurasian cabbage butterfly, Pieris rapae, shows a large geographic variation. The wings of the female of the European subspecies, P. rapae rapae, refle...Reflection of ultraviolet （UV） light by the wings of the female Eurasian cabbage butterfly, Pieris rapae, shows a large geographic variation. The wings of the female of the European subspecies, P. rapae rapae, reflect little UV light, while butterflies of the Asian subspecies, P. rapae crucivora, may reflect it strongly or at only intermediate levels. The geographic region where P. rapae originated remains to be determined, Moreover, it is not clear if females with wings that reflect little UV light are ancestral to females with wings that reflect UV strongly or vice versa. In the present study, we aimed to determine the geographic origin and ancestral UV pattern of cabbage butterflies through mitochondrial DNA （mtDNA） sequence analysis and amplified fragment length polymorphism （AFLP） analysis. The results of these investigations suggest that P. rapae is of European origin and that it has expanded its distribution eastward to Asia. It follows that the ancestral subspecies is the type with UV-absorbing wings. Lower nucleotide diversities and haplotype network patterns ofmtDNA derived from East Asian populations suggest that population expansion from Europe to East Asia probably occurred fairly recently and at a rapid rate.展开更多
The subject of our investigation was the visual features of wing color with special focus on the UV reflectance in the green-veined white butterfly （Pieris napi）. Previous studies had concluded that UV reflectance o...The subject of our investigation was the visual features of wing color with special focus on the UV reflectance in the green-veined white butterfly （Pieris napi）. Previous studies had concluded that UV reflectance on dorsal wing surfaces is found only in the female P napi. Based on UV sensitive photography, we analyzed a correlation between 12 geographic and environmental factors and UV reflectance patterns on 3 patches on the forewings of 407 P. napi specimens from the Palaearctic region. Results had shown that females significantly differ from males： they exhibit a 25% higher UV reflectance. To investigate whether and how UV reflectance levels on the forewings and hindwings of both sexes are influenced by the environment, we performed a principal component analysis （PCA） with several environmental variables. For several variables （in particular, latitude and longitude, mean annual temperature and precipitation, and temperature annual range and altitude）, the generalized linear model （GLM） model revealed a significant correlation in both sexes. This suggests a link between UV reflectance levels and the environment and distribution of P. napi. We found that stronger UV reflectance is associated with generally more hostile environments and concluded that large-scale environmental factors influence the UV reflectance on the forewings of both male and female green-veined white butterflies.展开更多
Aims Alpine plants have to cope with intense ultraviolet(UV)radiation and its altitudinal changes.It has been argued that leaf UV reflec-tance and absorbance should play a central role in acclimation and adaptation to...Aims Alpine plants have to cope with intense ultraviolet(UV)radiation and its altitudinal changes.It has been argued that leaf UV reflec-tance and absorbance should play a central role in acclimation and adaptation to changes in UV radiation,but evidence is lim-ited from high altitudinal ecosystems.In this study,we assessed whether leaf UV reflectance and leaf pigments jointly vary with altitude in alpine broadleaved herbaceous species.The primary hypothesis is that leaves with higher UV reflectance should have lower UV absorbance and/or lower contents of photosynthetic pigments.Methods Leaf UV reflectance,leaf UV absorbance and photosynthetic pig-ments(chlorophyll a and b,carotenoids)were examined in four broadleaved herbaceous species in relation to their habitat alti-tudes.The leaf surface reflectance and leaf extract absorbance at wavelengths of 305 and 360 nm were measured to examine the leaf optical and photochemical characteristics in the UV-B and UV-A bands,respectively.The species included Saussurea katochaete Maxim.,Saussurea pulchra Lipsch.,Anaphalis lactea Maxim.and Rheum pumilum Maxim.,which are distributed along the same slope from 3200 to 4200 m in the Qilian Mountains,Qinghai-Tibetan Plateau.Important Findings The leaf UV absorbance was approximately twice as high at 305 nm(UV-B)than at 360 nm(UV-A)for all species except R.pumilum.Among the four species,the leaf UV absorbance was the highest and almost all values were within 2-6 Abs cm^(−2)(absorbance cm^(−2))in S.pulchra,but the lowest(frequently<1 Abs cm^(−2))were observed in R.pumilum.Only R.pumilum showed significantly higher values at higher elevations.Leaf UV reflectance was generally higher at higher elevations for all species except for A.lactea,and exhibited much larger altitudinal variations compared to leaf UV absorbance.Anaphalis lactea showed a very high UV reflectance even at low altitudes.Among the four species,photosynthetic pigments tended to decrease with an increase in leaf UV reflectance but increased with leaf UV absorbance.The study suggests that leaf UV reflec-tance,rather than leaf UV absorbance,plays a more active role in acclimation to altitudinal changes in UV radiation,and a high investment in leaf UV reflectance may limit the accumulation of photosynthetic pigments in alpine plants.展开更多
Two new zincoborates,namely,Pb_(3)Ba_(3)Zn_(6)(BO_(3))_(8)andα-BaZn_(2)(BO_(3))_(2),were synthesized by the hightemperature solution method and their structures were determined by single-crystal X-ray diffraction for...Two new zincoborates,namely,Pb_(3)Ba_(3)Zn_(6)(BO_(3))_(8)andα-BaZn_(2)(BO_(3))_(2),were synthesized by the hightemperature solution method and their structures were determined by single-crystal X-ray diffraction for the first time.The structure of Pb_(3)Ba_(3)Zn_(6)(BO_(3))_(8)can be described as a three-dimensional framework consisting of[Zn_(4)B_(2)O_(15)]_(∞)chains and isolated ZnO_(4)tetrahedra and BO_(3)triangles,which contains three different types of tunnels with Pb_(2)+and Ba^(2+)cations residing among them.α-BaZn_(2)(BO_(3))_(2)exhibits a twodimensional layered structure with a[Zn_(2)B_(2)O_(6)]layer,which is formed by[ZnBO_(4)]chains and[Zn_(2)B_(2)O_(8)]chains.Interestingly,both Pb_(3)Ba_(3)Zn_(6)(BO_(3))_(8)andα-BaZn_(2)(BO_(3))_(2)both contain two different dimensional Zn-O configurations in their structures,which has not been found in other zincoborates.In addition,thermal property analysis,and UV-vis-NIR diffuse reflectance and infrared spectroscopy were also performed.First-principles theoretical studies were also conducted to aid the understanding of their band structures and densities of states.展开更多
Aims Bee-pollinated flowers are rarely red,presumably because bees(which lack red receptors)have difficulty detecting red targets.Although the response of bees to red colour has been investigated in lab experiments,mo...Aims Bee-pollinated flowers are rarely red,presumably because bees(which lack red receptors)have difficulty detecting red targets.Although the response of bees to red colour has been investigated in lab experiments,most stimuli have been pure red,while the subtle diversity of red as perceived by humans(human-red)has received very limited attention.Here we test the hypothesis that ultraviolet(UV)reflected from human-red flowers enhances their attractiveness to bees,through increased chromatic contrast.Methods Using Onosma confertum(Boraginaceae),a plant with UV-reflecting red flowers that are pollinated by bumblebees,we investigated the effects of UV reflection on pollinator responses by conducting phenotypic manipulation experiments in the field.Colour preferences of flower-naïve bumblebees were also examined.Colour perception by bumblebees was estimated in terms of chromatic and achromatic contrast,based on two different colour perception models.Important Findings We found that both natural and flower-naïve bumblebees strongly preferred visiting UV-reflecting targets compared with UV-absorbing ones.Colour models show that the UV-reflecting flowers exhibit higher spectral purity and higher chromatic contrast against the foliage background,whereas they have similar achromatic contrast in terms of green receptor contrast.These results indicate that the component of UV reflection increases chromatic contrast in O.confertum,enhancing the visual attractiveness of these red flowers to bumblebees.We further infer that the secondary reflectance might be a necessary component in human-red flowers that are primarily pollinated by animals without red receptors,such as bees.展开更多
基金funded by the State Scholarship Fund(201908500062)of China Scholarship Council。
文摘Males of Platycnemis latipes (Platycnemididae, Odonata) have enlarged tibiae (fans) and patrol using a special longitudinal zig-zag flight. By means of focal observations and experimental manipulations of the colour of abdomen and fans of mature males, we suggest that the zig-zag flight is used to avoid unnecessary harassment from other males and has not the function to attract females. The fans of P. latipes are mainly used as a tool to threaten rivals, but their effectiveness seems limited. Both abdomen and fans of a mature male can reflect UV light strongly.
文摘Reflection of ultraviolet （UV） light by the wings of the female Eurasian cabbage butterfly, Pieris rapae, shows a large geographic variation. The wings of the female of the European subspecies, P. rapae rapae, reflect little UV light, while butterflies of the Asian subspecies, P. rapae crucivora, may reflect it strongly or at only intermediate levels. The geographic region where P. rapae originated remains to be determined, Moreover, it is not clear if females with wings that reflect little UV light are ancestral to females with wings that reflect UV strongly or vice versa. In the present study, we aimed to determine the geographic origin and ancestral UV pattern of cabbage butterflies through mitochondrial DNA （mtDNA） sequence analysis and amplified fragment length polymorphism （AFLP） analysis. The results of these investigations suggest that P. rapae is of European origin and that it has expanded its distribution eastward to Asia. It follows that the ancestral subspecies is the type with UV-absorbing wings. Lower nucleotide diversities and haplotype network patterns ofmtDNA derived from East Asian populations suggest that population expansion from Europe to East Asia probably occurred fairly recently and at a rapid rate.
文摘The subject of our investigation was the visual features of wing color with special focus on the UV reflectance in the green-veined white butterfly （Pieris napi）. Previous studies had concluded that UV reflectance on dorsal wing surfaces is found only in the female P napi. Based on UV sensitive photography, we analyzed a correlation between 12 geographic and environmental factors and UV reflectance patterns on 3 patches on the forewings of 407 P. napi specimens from the Palaearctic region. Results had shown that females significantly differ from males： they exhibit a 25% higher UV reflectance. To investigate whether and how UV reflectance levels on the forewings and hindwings of both sexes are influenced by the environment, we performed a principal component analysis （PCA） with several environmental variables. For several variables （in particular, latitude and longitude, mean annual temperature and precipitation, and temperature annual range and altitude）, the generalized linear model （GLM） model revealed a significant correlation in both sexes. This suggests a link between UV reflectance levels and the environment and distribution of P. napi. We found that stronger UV reflectance is associated with generally more hostile environments and concluded that large-scale environmental factors influence the UV reflectance on the forewings of both male and female green-veined white butterflies.
基金This study was supported by the National Natural Science Foundation of China(31570399)partly by Qinghai innovation platform construction project(2017-ZJ-Y20).
文摘Aims Alpine plants have to cope with intense ultraviolet(UV)radiation and its altitudinal changes.It has been argued that leaf UV reflec-tance and absorbance should play a central role in acclimation and adaptation to changes in UV radiation,but evidence is lim-ited from high altitudinal ecosystems.In this study,we assessed whether leaf UV reflectance and leaf pigments jointly vary with altitude in alpine broadleaved herbaceous species.The primary hypothesis is that leaves with higher UV reflectance should have lower UV absorbance and/or lower contents of photosynthetic pigments.Methods Leaf UV reflectance,leaf UV absorbance and photosynthetic pig-ments(chlorophyll a and b,carotenoids)were examined in four broadleaved herbaceous species in relation to their habitat alti-tudes.The leaf surface reflectance and leaf extract absorbance at wavelengths of 305 and 360 nm were measured to examine the leaf optical and photochemical characteristics in the UV-B and UV-A bands,respectively.The species included Saussurea katochaete Maxim.,Saussurea pulchra Lipsch.,Anaphalis lactea Maxim.and Rheum pumilum Maxim.,which are distributed along the same slope from 3200 to 4200 m in the Qilian Mountains,Qinghai-Tibetan Plateau.Important Findings The leaf UV absorbance was approximately twice as high at 305 nm(UV-B)than at 360 nm(UV-A)for all species except R.pumilum.Among the four species,the leaf UV absorbance was the highest and almost all values were within 2-6 Abs cm^(−2)(absorbance cm^(−2))in S.pulchra,but the lowest(frequently<1 Abs cm^(−2))were observed in R.pumilum.Only R.pumilum showed significantly higher values at higher elevations.Leaf UV reflectance was generally higher at higher elevations for all species except for A.lactea,and exhibited much larger altitudinal variations compared to leaf UV absorbance.Anaphalis lactea showed a very high UV reflectance even at low altitudes.Among the four species,photosynthetic pigments tended to decrease with an increase in leaf UV reflectance but increased with leaf UV absorbance.The study suggests that leaf UV reflec-tance,rather than leaf UV absorbance,plays a more active role in acclimation to altitudinal changes in UV radiation,and a high investment in leaf UV reflectance may limit the accumulation of photosynthetic pigments in alpine plants.
基金supported by National Natural Science Foundation of China(Grant No.51972230 and 61975096)Research and Free Exploration Project of Shenzhen City(Grant No.JCYJ20180305164316517)Natural Science Foundation of Shandong Province(Grant No.ZR2017MF031).
文摘Two new zincoborates,namely,Pb_(3)Ba_(3)Zn_(6)(BO_(3))_(8)andα-BaZn_(2)(BO_(3))_(2),were synthesized by the hightemperature solution method and their structures were determined by single-crystal X-ray diffraction for the first time.The structure of Pb_(3)Ba_(3)Zn_(6)(BO_(3))_(8)can be described as a three-dimensional framework consisting of[Zn_(4)B_(2)O_(15)]_(∞)chains and isolated ZnO_(4)tetrahedra and BO_(3)triangles,which contains three different types of tunnels with Pb_(2)+and Ba^(2+)cations residing among them.α-BaZn_(2)(BO_(3))_(2)exhibits a twodimensional layered structure with a[Zn_(2)B_(2)O_(6)]layer,which is formed by[ZnBO_(4)]chains and[Zn_(2)B_(2)O_(8)]chains.Interestingly,both Pb_(3)Ba_(3)Zn_(6)(BO_(3))_(8)andα-BaZn_(2)(BO_(3))_(2)both contain two different dimensional Zn-O configurations in their structures,which has not been found in other zincoborates.In addition,thermal property analysis,and UV-vis-NIR diffuse reflectance and infrared spectroscopy were also performed.First-principles theoretical studies were also conducted to aid the understanding of their band structures and densities of states.
基金supported by the Key Projects of the Joint Fund of the National Natural Science Foundation of China(U1802232 to H.S.)the Second Tibetan Plateau Scientific Expedition and Research(STEP)programme(2019QZKK0502)+2 种基金Ministry of Science and Technology of the People’s Republic of China,National Natural Science Foundation of China(31670214 to Y.N.)the Youth Innovation Promotion Association,Chinese Academy of Sciences(2018427 to Y.N.)Yunnan Ten Thousand Talents Plan Young&Elite Talents Project,Science&Technology Department of Yunnan Province.
文摘Aims Bee-pollinated flowers are rarely red,presumably because bees(which lack red receptors)have difficulty detecting red targets.Although the response of bees to red colour has been investigated in lab experiments,most stimuli have been pure red,while the subtle diversity of red as perceived by humans(human-red)has received very limited attention.Here we test the hypothesis that ultraviolet(UV)reflected from human-red flowers enhances their attractiveness to bees,through increased chromatic contrast.Methods Using Onosma confertum(Boraginaceae),a plant with UV-reflecting red flowers that are pollinated by bumblebees,we investigated the effects of UV reflection on pollinator responses by conducting phenotypic manipulation experiments in the field.Colour preferences of flower-naïve bumblebees were also examined.Colour perception by bumblebees was estimated in terms of chromatic and achromatic contrast,based on two different colour perception models.Important Findings We found that both natural and flower-naïve bumblebees strongly preferred visiting UV-reflecting targets compared with UV-absorbing ones.Colour models show that the UV-reflecting flowers exhibit higher spectral purity and higher chromatic contrast against the foliage background,whereas they have similar achromatic contrast in terms of green receptor contrast.These results indicate that the component of UV reflection increases chromatic contrast in O.confertum,enhancing the visual attractiveness of these red flowers to bumblebees.We further infer that the secondary reflectance might be a necessary component in human-red flowers that are primarily pollinated by animals without red receptors,such as bees.
