In general, female fitness is greatly increased in gift-giving insects. In katydids, this nuptial gift consists of a gelatinous mass produced by accessory glands： the spermato- phylax, which is attached to the ampull...In general, female fitness is greatly increased in gift-giving insects. In katydids, this nuptial gift consists of a gelatinous mass produced by accessory glands： the spermato- phylax, which is attached to the ampulla. During mating, males of the neotropical katydid Conocephalus ictus transfer a spermatophylax that is ingested by the females. Fecundity, egg-laying rate and longevity were higher in females that consumed the spermatophylax than in those that did not. Also, female receptivity turned off after mating. Females actively rejected other males by hitting them with their forelegs and moving away. Their refractory period lasted as long as 17 d. Only a few females accepted a 2nd mating and died a few days later. In C. ictus, spermatophylax consumption can be beneficial for both males and females. On one hand, the compounds in the spermatophylax or the ejaculate could prevent or delay females from copulating with rivals, thus avoiding sperm competition. On the other hand, such compounds can improve the females＇ opportunity to increase their lifespan and fecundity. Moreover, a rise in egg-laying rate may lower the risk of female prereproductive death caused by rapid oviposition. In any case, the boost in female egg laying might also be beneficial for males because their number of offspring increases.展开更多
Many insect families have evolved to produce and detect complex singing patterns for the purposes of mating, display of dominance, predator escape, and other needs. While the mechanisms of sound production by insects ...Many insect families have evolved to produce and detect complex singing patterns for the purposes of mating, display of dominance, predator escape, and other needs. While the mechanisms of sound production by insects have been thoroughly studied, man-machine exploitation of such mechanisms has remained unreported. We therefore describe a method to modulate the frequency spectrum in the chirp call of a singing insect, Gampsocleis gratiosa （Orthoptera： Tettigoniidae）, a large katydid indigenous to China and commonly known as Guo Guo or Chinese Bush Cricket. The chirp modulation was achieved through the contact of a ribbon of lonic Polymer-Metal Composite （IPMC） against wing of the insect. The IPMC effectively served as an actuator when a small DC voltage was applied to the ribbon＇s faces. By applying a sequential on/off voltage waveform to the IPMC ribbon, the katydid＇s chirp was modulated in a corresponding manner. This configuration can be used as part of a broader application of using singing insects to harness their acoustic power to produce and propagate machine-induced messages into the acoustic environment.展开更多
The art of carving oxbone crafts goes back 300 years. The crafts vary in style and are most commonly found in Yixian County, Hebei Province. These crafts are made from the hipbone and legbone of the ox. The exquisite ...The art of carving oxbone crafts goes back 300 years. The crafts vary in style and are most commonly found in Yixian County, Hebei Province. These crafts are made from the hipbone and legbone of the ox. The exquisite carving of the cabbage and intricate inlay work of the katydid is especially vivid. The carving is associated with the natural world in autumn.展开更多
It is found that many biological organisms exhibit superior adhesion characteristics in wet environments. It has been observed that the foot pads of tree frogs and katydids are consist of a number of closely arranged ...It is found that many biological organisms exhibit superior adhesion characteristics in wet environments. It has been observed that the foot pads of tree frogs and katydids are consist of a number of closely arranged polygons, most of them are hexagonal. In this paper, the common structure of two kinds of biological foot pad was extracted to model the bionic surface structure of friction plates. The friction plate prototypes were also prepared. Through the multivariate orthogonal regression design, the optimum parameter combination of the friction performances of the prototypes of the bionic plates has been obtained. The hexagonal circumcircle size is 10 mm, the groove width is 1 mm, and the hexagonal diagonal angle is 90~. Then the maximum static friction coefficient, dynamic friction coefficient and wear amount of the optimal friction plate were tested and compared with the control group friction plates. The comparative analysis of the experiment findings demonstrated that the bionic structure with hexagonal ring grooves can significantly improve the friction performance of the friction plates.展开更多
文摘In general, female fitness is greatly increased in gift-giving insects. In katydids, this nuptial gift consists of a gelatinous mass produced by accessory glands： the spermato- phylax, which is attached to the ampulla. During mating, males of the neotropical katydid Conocephalus ictus transfer a spermatophylax that is ingested by the females. Fecundity, egg-laying rate and longevity were higher in females that consumed the spermatophylax than in those that did not. Also, female receptivity turned off after mating. Females actively rejected other males by hitting them with their forelegs and moving away. Their refractory period lasted as long as 17 d. Only a few females accepted a 2nd mating and died a few days later. In C. ictus, spermatophylax consumption can be beneficial for both males and females. On one hand, the compounds in the spermatophylax or the ejaculate could prevent or delay females from copulating with rivals, thus avoiding sperm competition. On the other hand, such compounds can improve the females＇ opportunity to increase their lifespan and fecundity. Moreover, a rise in egg-laying rate may lower the risk of female prereproductive death caused by rapid oviposition. In any case, the boost in female egg laying might also be beneficial for males because their number of offspring increases.
文摘Many insect families have evolved to produce and detect complex singing patterns for the purposes of mating, display of dominance, predator escape, and other needs. While the mechanisms of sound production by insects have been thoroughly studied, man-machine exploitation of such mechanisms has remained unreported. We therefore describe a method to modulate the frequency spectrum in the chirp call of a singing insect, Gampsocleis gratiosa （Orthoptera： Tettigoniidae）, a large katydid indigenous to China and commonly known as Guo Guo or Chinese Bush Cricket. The chirp modulation was achieved through the contact of a ribbon of lonic Polymer-Metal Composite （IPMC） against wing of the insect. The IPMC effectively served as an actuator when a small DC voltage was applied to the ribbon＇s faces. By applying a sequential on/off voltage waveform to the IPMC ribbon, the katydid＇s chirp was modulated in a corresponding manner. This configuration can be used as part of a broader application of using singing insects to harness their acoustic power to produce and propagate machine-induced messages into the acoustic environment.
文摘The art of carving oxbone crafts goes back 300 years. The crafts vary in style and are most commonly found in Yixian County, Hebei Province. These crafts are made from the hipbone and legbone of the ox. The exquisite carving of the cabbage and intricate inlay work of the katydid is especially vivid. The carving is associated with the natural world in autumn.
文摘It is found that many biological organisms exhibit superior adhesion characteristics in wet environments. It has been observed that the foot pads of tree frogs and katydids are consist of a number of closely arranged polygons, most of them are hexagonal. In this paper, the common structure of two kinds of biological foot pad was extracted to model the bionic surface structure of friction plates. The friction plate prototypes were also prepared. Through the multivariate orthogonal regression design, the optimum parameter combination of the friction performances of the prototypes of the bionic plates has been obtained. The hexagonal circumcircle size is 10 mm, the groove width is 1 mm, and the hexagonal diagonal angle is 90~. Then the maximum static friction coefficient, dynamic friction coefficient and wear amount of the optimal friction plate were tested and compared with the control group friction plates. The comparative analysis of the experiment findings demonstrated that the bionic structure with hexagonal ring grooves can significantly improve the friction performance of the friction plates.
基金Supported by the National Natural Science Foundation of China(31760014)the Science and Technology Foundations of Guizhou Province([2019]2451-3,[2016]2863).
