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1.
卧龙自然保护区野生大熊猫繁殖研究 总被引:11,自引:4,他引:7
本文分析了1978-1992年在卧龙自然保护区五一棚研究区内的野生大熊猫繁殖情况,结果表明:野生大熊猫雌体6.5岁初发情,7.5岁交配产仔,20岁繁殖基本停止;雄体7.5岁初发情,8.5岁能获交配权,20岁繁殖基本停止。年繁殖率为62.5%,其中单胞胎为58.33%,双胞胎为4.17%。此外,1983年冷箭竹开花枯死,延迟了大熊猫的发情期,这可能与竹了开后大熊猫觅食行为改变及摄入影响繁殖的微量元素 相似文献
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正Since the publication of The Origin of Species by Charles Darwin, evolutionary biology has developed into a key discipline of biology and experienced several important expansions contributed by the sequential integration of Mendelian genetics, Morgan’s chromosome heredity mechanism, and Crick’s genetic central dogma theory. Especially in recent decades, next-generation sequencing has 相似文献
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Phylogenetic relationships among 15 species of wood mice (genus Apodemus) were reconstructed to explore some long-standing taxonomic problems. The results provided support for the monophyly of the genus Apodemus, but could not reject the hypothesis of paraphyly for this genus. Our data divided the 15 species into four major groups: (1) the Sylvaemus group (A. sylvaticus, A. flavicollis, A. alpicola, and A. uralensis), (2) the Apodemus group (A. peninsulae, A. chevreri, A. agrarius, A. speciosus, A. draco, A. ilex, A. semotus, A. latronum, and A. mystacinus), (3) A. argenteus, and (4) A. gurkha. Our results also suggested that orestes should be a valid subspecies of A. draco rather than an independent species; in contrast, A. ilex from Yunnan may be regarded as a separate species rather than a synonym of orestes or draco. The species level status of A. latronum, tscherga as synonyms of A. uralensis, and A. chevrieri as a valid species and the closest sibling species of A. agrarius were further corroborated by our data. Applying a molecular clock with the divergences of Mus and Rattus set at 12 million years ago (Mya) as a calibration point, it was estimated that five old lineages (A. mystacinus and four major groups above) diverged in the late Miocene (7.82-12.74 Mya). Then the Apodemus group (excluding A. mystacinus) split into two subgroups: agrarius and draco, at about 7.17-9.95 Mya. Four species of the Sylvaemus group were estimated to diverge at about 2.92-5.21 Mya. The Hengduan Mountains Region was hypothesized to have played important roles in Apodemus evolutionary histories since the Pleistocene. 相似文献
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In order to analyze, separately and dynamically, the variation in cranial size and shape of Chinese macaques, a new method, Morphologika, was used to illustrate 3D profiles based on the coordinates of 26 landmarks on the skull. Striking image variation between the two sexes was detected on the facial region: males exhibited a larger and more protrusive facial structure. Males also displayed a bigger cranium than females. The two sexes also showed quite different images in skull shape. However, they expressed the same allometric pattern with regard to the relationship between size and shape, which was significantly positively associated with each other along the first axis. The same relationship was negatively displayed along the second axis when the two sexes were analyzed together. However, only the relationship for females reached a significant level when the two sexes were studied separately. This was considered to be related to their differentiation in growth trajectory. This study also tested the concept of size revealed by the second axis of principal components analysis based on traditional morphometric methods on the same taxa. 相似文献
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Xiangjiang Zhan Xiudeng Zheng Michael W. Bruford Fuwen Wei Yi Tao 《Conservation Genetics》2010,11(4):1567-1571
More and more noninvasive genetic data are being produced but a general methodology to quantify genotyping error rates from
non-pilot data remains lacking. Here we propose a mathematical approach to estimate genotyping error rates by exploring the
relationship between errors and PCR replicates. This method can be used to quantify the error rates for either the multi-tubes
approach designed by Taberlet et al. (Nucleic Acids Res 24: 3189–3194, 1996) or the pilot method by Prugh et al. (Mol Ecol 14: 1585–1596, 2005). 相似文献
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Understanding the spatial genetic structure of populations can provide insight into the ecological or evolutionary processes
of the species, and enable wise conservation decisions. We examined the spatial genetic structure of a giant panda (Ailuropoda melanoleuca) population in a heterogeneous mountainous landscape using noninvasive genetic sampling and 12 microsatellite loci. Nonrandom
genetic structure was detected through spatial autocorrelation analysis, demonstrating a significantly positive autocorrelation
over closer distances. Additional spatial analyses showed significantly positive genetic correlation among spatially-proximate
males, and no correlation among females and among male–female pairs. These findings suggest a female-biased dispersal pattern
and cryptic family grouping among giant pandas on a large mountain-range scale. The spatial extent of genetic structure occurred
within 12.5 km, measured by a least-cost path distance model integrating information of habitat quality and habitat preferences
of this species. Using the bearing analysis of PASSAGE, we found that directional genetic autocorrelations were in agreement
with habitat structure, and habitat heterogeneity may affect the direction of giant panda dispersal. The characterization
of spatial genetic structure can provide potentially valuable information for the conservation and management of giant pandas
and their habitat. 相似文献
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Qihai Zhou Fuwen Wei Chengming Huang Ming Li Baoping Ren Bang Luo 《International journal of primatology》2007,28(3):657-671
Activity patterns and time budgets are 2 important aspects of animal behavior that researchers use to investigate ecological influences on individual behavior. We collected data on activity patterns and time budgets in 1 group of François’ langurs (Trachypithecus francoisi) from August 2003 to July 2004 in the Nonggang Nature Reserve, Guangxi Province, China, via instantaneous scan sampling method with 15-min intervals. The diurnal activity pattern of François’ langurs showed morning and afternoon feeding peaks, with a midday resting peak. Seasonal change was apparent in the activity pattern: 2 significant feeding peaks occurred in the dry season and only 1 significant feeding peak in the rainy season. The group spent an average of 51.5% of the daytime resting. Feeding and moving accounted on average for 23.1% and 17.3% of the activity budget, respectively. Subjects spent little time on social activities, averaging 2% for grooming and 5.5% for playing. Their time budgets showed significant seasonal variation: they spent a greater proportion of time on feeding and less time on resting and grooming in the dry season than in the rainy season. They also differed among different sex-age classes: immatures spent more time playing, whereas adults devoted more time to resting, feeding, and grooming. Correlations between time budgets and food items or food availability clearly indicated that François’ langurs might adopt an energy-maximizing strategy when preferred foods were scarce in the dry season. 相似文献