[Objective] Genomic in situ hybridization (GISH) was used to study the relationship between the two CCDD genomes of Oryza alta and Oryza latifolia. [Method] Total DNA of Oryza officinalis (C-genome) was used as a prob...[Objective] Genomic in situ hybridization (GISH) was used to study the relationship between the two CCDD genomes of Oryza alta and Oryza latifolia. [Method] Total DNA of Oryza officinalis (C-genome) was used as a probe for genomic in situ hybridization on metaphase chromosomes from Oryza alta and Oryza latifolia, respectively. [Result] Under certain post-hybridization washing stringencies, C- and D-genome could be distinguished in CCDD genome type; there were huge differences in some CC chromosomes of Oryza alta, Oryza latifolia, and Oryza officinalis. The genome of Oryza latifolia was more original. [Conclusion] Comparative analysis of the Oryza species with identical genome type may facilitate to elucidate the possible approaches to plant genome evolution and species evolution.展开更多
Three wild populations of Meretrix meretrix sampled from Dongxing, Beihai, and Shankou along the coast of Guangxi, China, were investigated with morphometry and karyometry. Six morphological indices (shell length, she...Three wild populations of Meretrix meretrix sampled from Dongxing, Beihai, and Shankou along the coast of Guangxi, China, were investigated with morphometry and karyometry. Six morphological indices (shell length, shell height, shell width, hinge length, total wet weight and shell weight) were measured. Differences in all morphological indices except hinge length were significant among the three populations (P < 0.05). The mean values of these indices (except for the hinge length) in the Dongxing population were larger than those in the Beihai and Shankou populations, although the latter had the largest hinge length. The karyotype of the Beihai, Shankou and Dongxing samples had ten metacentric, six submetacentric, and three subtelocentric chromosome pairs. No significant difference was shown in the centromeric index values of the chromosomes in the populations (P>0.05). However, the order of metacentric, submetacentric and subtelocentric chromosome pairs was variable among the three populations. The results indicate a high level of inter-population variation in morphology and karyotype.展开更多
The infrared camera is a curious object for the animals of Changtang.Often covered in camouflage or army green,it looks very"professional".But once I saw the photos they took,I knew the camouflage did not wo...The infrared camera is a curious object for the animals of Changtang.Often covered in camouflage or army green,it looks very"professional".But once I saw the photos they took,I knew the camouflage did not work at all.Most animals could see the cameras without any problem.Some of them showed various degrees of interest in the cameras,while others acted indifferently.To tell the truth,it is not easy to hide something in Changtang.展开更多
Signals used for species identity ought to be highly stereotyped so as to facilitate immediate recognition by conspecifics. It is surprising therefore to find variability in putative species signature displays. The br...Signals used for species identity ought to be highly stereotyped so as to facilitate immediate recognition by conspecifics. It is surprising therefore to find variability in putative species signature displays. The brown anole Anolis sagrei has a high degree of variability in its signature bobbing display. In this study we collected descriptive data on variability in the temporal structure of wild brown anole bobbing patterns, finding that no two displays analyzed had the same temporal structure, and we also tested whether wild brown anoles prefer the signature display over an alternate display pattern by using mechanical robot playbacks in the field. As a response metric we assessed whether or not the lizards showed social responses （pushup, dewlap extension, or head-nod） in response to the robotic presentations. We found that the lizards responded slightly more to the signature than to the alternate pattern, providing support for the idea that despite the variability seen in displays, the signature pattern is meaningful to them. We tested two other independent variables： speed of the display and elevation of the robot during its display, neither of which was significant. Dewlap extensions were given predominantly by adult males and were more likely to be given in the breeding season than the nonbreeding season. Pushups and head-nods were given equally by males and a combined class of females and juveniles, and were not seasonal. Head-nods increased after the robot turned off, suggesting that they may be used in a conversational turn-taking style during communication .展开更多
文摘[Objective] Genomic in situ hybridization (GISH) was used to study the relationship between the two CCDD genomes of Oryza alta and Oryza latifolia. [Method] Total DNA of Oryza officinalis (C-genome) was used as a probe for genomic in situ hybridization on metaphase chromosomes from Oryza alta and Oryza latifolia, respectively. [Result] Under certain post-hybridization washing stringencies, C- and D-genome could be distinguished in CCDD genome type; there were huge differences in some CC chromosomes of Oryza alta, Oryza latifolia, and Oryza officinalis. The genome of Oryza latifolia was more original. [Conclusion] Comparative analysis of the Oryza species with identical genome type may facilitate to elucidate the possible approaches to plant genome evolution and species evolution.
基金Supported by the Natural Science Foundation of Guangdong Province (2002C60115)the foundation of Guangdong Ocean University (E06031).
文摘Three wild populations of Meretrix meretrix sampled from Dongxing, Beihai, and Shankou along the coast of Guangxi, China, were investigated with morphometry and karyometry. Six morphological indices (shell length, shell height, shell width, hinge length, total wet weight and shell weight) were measured. Differences in all morphological indices except hinge length were significant among the three populations (P < 0.05). The mean values of these indices (except for the hinge length) in the Dongxing population were larger than those in the Beihai and Shankou populations, although the latter had the largest hinge length. The karyotype of the Beihai, Shankou and Dongxing samples had ten metacentric, six submetacentric, and three subtelocentric chromosome pairs. No significant difference was shown in the centromeric index values of the chromosomes in the populations (P>0.05). However, the order of metacentric, submetacentric and subtelocentric chromosome pairs was variable among the three populations. The results indicate a high level of inter-population variation in morphology and karyotype.
文摘The infrared camera is a curious object for the animals of Changtang.Often covered in camouflage or army green,it looks very"professional".But once I saw the photos they took,I knew the camouflage did not work at all.Most animals could see the cameras without any problem.Some of them showed various degrees of interest in the cameras,while others acted indifferently.To tell the truth,it is not easy to hide something in Changtang.
文摘Signals used for species identity ought to be highly stereotyped so as to facilitate immediate recognition by conspecifics. It is surprising therefore to find variability in putative species signature displays. The brown anole Anolis sagrei has a high degree of variability in its signature bobbing display. In this study we collected descriptive data on variability in the temporal structure of wild brown anole bobbing patterns, finding that no two displays analyzed had the same temporal structure, and we also tested whether wild brown anoles prefer the signature display over an alternate display pattern by using mechanical robot playbacks in the field. As a response metric we assessed whether or not the lizards showed social responses （pushup, dewlap extension, or head-nod） in response to the robotic presentations. We found that the lizards responded slightly more to the signature than to the alternate pattern, providing support for the idea that despite the variability seen in displays, the signature pattern is meaningful to them. We tested two other independent variables： speed of the display and elevation of the robot during its display, neither of which was significant. Dewlap extensions were given predominantly by adult males and were more likely to be given in the breeding season than the nonbreeding season. Pushups and head-nods were given equally by males and a combined class of females and juveniles, and were not seasonal. Head-nods increased after the robot turned off, suggesting that they may be used in a conversational turn-taking style during communication .
