This paper presents a mechanical model of jumping robot based on the biological mechanism analysis of frog. By biological observation and kinematic analysis the frog jump is divided into take-offphase, aerial phase an...This paper presents a mechanical model of jumping robot based on the biological mechanism analysis of frog. By biological observation and kinematic analysis the frog jump is divided into take-offphase, aerial phase and landing phase. We find the similar trajectories of hindlimb joints during jump, the important effect of foot during take-off and the role of forelimb in supporting the body. Based on the observation, the frog jump is simplified and a mechanical model is put forward. The robot leg is represented by a 4-bar spring/linkage mechanism model, which has three Degrees of Freedom （DOF） at hip joint and one DOF （passive） at tarsometatarsal joint on the foot. The shoulder and elbow joints each has one DOF for the balancing function of arm. The ground reaction force of the model is analyzed and compared with that of frog during take-off. The results show that the model has the same advantages of low likelihood of premature lift-off and high efficiency as the frog. Analysis results and the model can be employed to develop and control a robot capable of mimicking the jumping behavior of frog.展开更多
South China and Indochina host striking species diversity and endemism. Complex tectonic and climatic evolutions appear to be the main drivers of the biogeographic patterns. In this study, based on the geologic histor...South China and Indochina host striking species diversity and endemism. Complex tectonic and climatic evolutions appear to be the main drivers of the biogeographic patterns. In this study, based on the geologic history of this region, we test 2 hypotheses using the evolutionary history of Microhyla fissipes species complex. Using DNA sequence data from both mitochondrial and nuclear genes, we first test the hypothesis that the Red River is a barrier to gene flow and dispersal. Second, we test the hypothesis that Pleistocene climatic cycling affected the genetic structure and population history of these frogs. We detect 2 major genetic splits that associate with the Red River. Time estimation suggests that late Miocene tectonic movement associated with the Red River drove their diversification. Species distribution modeling （SDM） resolves significant ecolo- gical differences between sides of the Red River. Thus, ecological divergence also probably promoted and maintained the diversification. Genogeography, historical demography, and SDM associate patterns in southern China with climate changes of the last glacial maximum （LGM）, but not Indochina. Differences in geography and climate between the 2 areas best explain the discovery. Responses to the Pleistocene glacial-interglacial cycling vary among species and regions.展开更多
Genus Rhacophorus Kuhl and Van Hasselt, 1 822 is one of the most diverse genera of the family Rhacophoridae, and its taxonomy of genus Rhacophorus faces major challenges because of rapidly described new species and co...Genus Rhacophorus Kuhl and Van Hasselt, 1 822 is one of the most diverse genera of the family Rhacophoridae, and its taxonomy of genus Rhacophorus faces major challenges because of rapidly described new species and complex interspecies relations. In this study, we investigate the generic taxonomy within the genus Rhacophorus based on 1 972 bp of mitochondrial genes(12S rRNA, tRNA-val and 16S rRNA), containing 102 sequences from 58 species. The results reveal three well-supported and highly diverged matrilines that correspond with morphological characteristics and geographic distribution. Accordingly, we consider these three lineages as distinct genera: Rhacophorus sensu stricto, resurrected genus Leptomantis Peters, 1867, and the genus Zhangixalus gen. nov.展开更多
基金the National High Technology Research and Development Program of China (No.2006AA04Z245)Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT) (IRT0423)
文摘This paper presents a mechanical model of jumping robot based on the biological mechanism analysis of frog. By biological observation and kinematic analysis the frog jump is divided into take-offphase, aerial phase and landing phase. We find the similar trajectories of hindlimb joints during jump, the important effect of foot during take-off and the role of forelimb in supporting the body. Based on the observation, the frog jump is simplified and a mechanical model is put forward. The robot leg is represented by a 4-bar spring/linkage mechanism model, which has three Degrees of Freedom （DOF） at hip joint and one DOF （passive） at tarsometatarsal joint on the foot. The shoulder and elbow joints each has one DOF for the balancing function of arm. The ground reaction force of the model is analyzed and compared with that of frog during take-off. The results show that the model has the same advantages of low likelihood of premature lift-off and high efficiency as the frog. Analysis results and the model can be employed to develop and control a robot capable of mimicking the jumping behavior of frog.
基金Acknowledgments We thank Sheng-guo Fang, Hal-tan Shi, Li-jun Wang, Li-min Ding, Yun-yu Wang, Ban-ling Zhang, Hai-peng Zhao, Jin-ming Chen, Jun-xiao Yang, Jia-jun Zhou, Gang Yao, Nikolai L. Orlov, Son Nguyen Truong, Tao Thien Nguyen, Truong Quang Nguyen, Tran Ngoc Ninh, Ba Dinh Vo, Andrei N. Kuznetsov, Leonid P. Korzoun, Anna B. Vassilieva, Eduard A. Galoyan, Igor V. Palko, Suwat Seaya, and Prakayjit Saengham for helping with sample col- lections. We thank the local Forestry Department and National reserve helped for the fieldworks in China. We thank the Forestry Department of Thailand and Vietnam for permissions to undertake field survey, specimen collections and local national park for helping. The Institute of Animal for Scientific Purposes Development （IAD） issued permission （No.U1-01205-2558） in Thailand. The Department of Forestry, Ministry of Agriculture and Rural Development of Vietnam issued permission （permits No. 170/TCLN-BTI＇N, 982/TCLN-BTTN and 831/TCLN-BTTN） in Vietnam. For loans of tissues, we thank Amy Lathrop from the Royal Ontario Museum （ROM）, Toronto, Canada. We gratefully acknowledge Wei-wei Zhou and Yong-jie Wu for providing thoughtful comments during preparation of the previous version of this manuscript.This work was supported by the program of Chinese Academy of Sciences （2015CASEABRI002）, the Ministry of Science and Technology of China （2011FY120200）, the National Natural Science Foundation of China （31090250）, and the Animal Branch of the Germplasm Bank of Wild Species, Chinese Academy of Sciences （the Large Research Infrastructure Funding） to J. C. the Chinese Academy of Sciences Visiting Fellowship for Researchers （Postdoc） from Developing Countries （2013FFS130015） to C. S.+2 种基金 the National Natural Science Foundation of China （31501843） to H. M. C. the Russian Foundation of Basic Research （Grant No. RFBR Taiwan No. 14-04- 92000, 15-29-02771 and 15-04-02029） and the Russian Science Foundation （RSF grant No 14-50-00029） to N. A. P. NS
文摘South China and Indochina host striking species diversity and endemism. Complex tectonic and climatic evolutions appear to be the main drivers of the biogeographic patterns. In this study, based on the geologic history of this region, we test 2 hypotheses using the evolutionary history of Microhyla fissipes species complex. Using DNA sequence data from both mitochondrial and nuclear genes, we first test the hypothesis that the Red River is a barrier to gene flow and dispersal. Second, we test the hypothesis that Pleistocene climatic cycling affected the genetic structure and population history of these frogs. We detect 2 major genetic splits that associate with the Red River. Time estimation suggests that late Miocene tectonic movement associated with the Red River drove their diversification. Species distribution modeling （SDM） resolves significant ecolo- gical differences between sides of the Red River. Thus, ecological divergence also probably promoted and maintained the diversification. Genogeography, historical demography, and SDM associate patterns in southern China with climate changes of the last glacial maximum （LGM）, but not Indochina. Differences in geography and climate between the 2 areas best explain the discovery. Responses to the Pleistocene glacial-interglacial cycling vary among species and regions.
基金supported by National Key R&D Program of China (2016YFC1200705)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB31000000)+4 种基金the National Natural Science Foundation of China (31722049, 31772434)Key Research Program of Frontier Sciences, CAS (QYZDBSSW-SMC058)the Youth Innovation Promotion Association of CASSoutheast Asia Biodiversity Research Institute (Y4ZK111B01)the CAS "Light of West China" Program (2018XBZG_JCTD_001)
文摘Genus Rhacophorus Kuhl and Van Hasselt, 1 822 is one of the most diverse genera of the family Rhacophoridae, and its taxonomy of genus Rhacophorus faces major challenges because of rapidly described new species and complex interspecies relations. In this study, we investigate the generic taxonomy within the genus Rhacophorus based on 1 972 bp of mitochondrial genes(12S rRNA, tRNA-val and 16S rRNA), containing 102 sequences from 58 species. The results reveal three well-supported and highly diverged matrilines that correspond with morphological characteristics and geographic distribution. Accordingly, we consider these three lineages as distinct genera: Rhacophorus sensu stricto, resurrected genus Leptomantis Peters, 1867, and the genus Zhangixalus gen. nov.
