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51.
52.
高黎贡山赧亢白眉长臂猿春季食物选择 总被引:1,自引:0,他引:1
2007年3月9日—4月28日,在高黎贡山赧亢跟踪观察白眉长臂猿(Hoolock hoolock)的春季食性及取食行为,将其行为分为食果、食果汁和食叶。采用瞬时扫描法记录白眉长臂猿的取食行为,取食的种类、部位和地点等。在其活动区域内,以取食树为中心设置20m×20m的利用样方和以随机方式设置同样大小的可利用样方各19个。在样方内收集与取食树及食物资源相关的6个因子的数据。统计食物种类和资源量、选择指数、取食点的选择性等。结果表明,赧亢白眉长臂猿春季取食的食物共10种,其中果实类植物3种,果汁类植物1种,嫩叶类植物6种。10种食物中,白眉长臂猿对印度木荷(Schima khasiana)的果实和缅甸木莲(Maglietia haokeri)的嫩叶呈弱选择,对其他8种食物资源均呈强选择。Mann-WhitneyU-检验结果表明,利用样方和可利用样方间的食物资源量及食物种类数均差异极显著,以利用样方的资源量大,每一样方食物种类较多。果实是赧亢白眉长臂猿春季的主要食物资源,而嫩叶是补充。呈强选择的食物并不一定是取食频次高的食物;反之,取食频次高的食物也不一定呈强选择。白眉长臂猿常选择易处理的果实和粗灰分含量少的嫩叶,且果实是它摄取水分的主要来源。白眉长臂猿通常选择食物资源和种类相对集中的区域取食,这可以减少动物因寻找食物所耗费的能量,同时获得多种食物,满足其生理对营养的需求。 相似文献
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Samuel T. Turvey Jennifer J. Crees Martina M. I. Di Fonzo 《Proceedings. Biological sciences / The Royal Society》2015,282(1813)
Extinction events typically represent extended processes of decline that cannot be reconstructed using short-term studies. Long-term archives are necessary to determine past baselines and the extent of human-caused biodiversity change, but the capacity of historical datasets to provide predictive power for conservation must be assessed within a robust analytical framework. Local Chinese gazetteers represent a more than 400-year country-level dataset containing abundant information on past environmental conditions and include extensive records of gibbons, which have a restricted present-day distribution but formerly occurred across much of China. Gibbons show pre-twentieth century range contraction, with significant fragmentation by the mid-eighteenth century and population loss escalating in the late nineteenth century. Isolated gibbon populations persisted for about 40 years before local extinction. Populations persisted for longer at higher elevations, and disappeared earlier from northern and eastern regions, with the biogeography of population loss consistent with the contagion model of range collapse in response to human demographic expansion spreading directionally across China. The long-term Chinese historical record can track extinction events and human interactions with the environment across much longer timescales than are usually addressed in ecology, contributing novel baselines for conservation and an increased understanding of extinction dynamics and species vulnerability or resilience to human pressures. 相似文献
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Krishna R. Veeramah August E. Woerner Laurel Johnstone Ivo Gut Marta Gut Tomas Marques-Bonet Lucia Carbone Jeff D. Wall Michael F. Hammer 《Genetics》2015,200(1):295-308
Gibbons are believed to have diverged from the larger great apes ∼16.8 MYA and today reside in the rainforests of Southeast Asia. Based on their diploid chromosome number, the family Hylobatidae is divided into four genera, Nomascus, Symphalangus, Hoolock, and Hylobates. Genetic studies attempting to elucidate the phylogenetic relationships among gibbons using karyotypes, mitochondrial DNA (mtDNA), the Y chromosome, and short autosomal sequences have been inconclusive . To examine the relationships among gibbon genera in more depth, we performed second-generation whole genome sequencing (WGS) to a mean of ∼15× coverage in two individuals from each genus. We developed a coalescent-based approximate Bayesian computation (ABC) method incorporating a model of sequencing error generated by high coverage exome validation to infer the branching order, divergence times, and effective population sizes of gibbon taxa. Although Hoolock and Symphalangus are likely sister taxa, we could not confidently resolve a single bifurcating tree despite the large amount of data analyzed. Instead, our results support the hypothesis that all four gibbon genera diverged at approximately the same time. Assuming an autosomal mutation rate of 1 × 10−9/site/year this speciation process occurred ∼5 MYA during a period in the Early Pliocene characterized by climatic shifts and fragmentation of the Sunda shelf forests. Whole genome sequencing of additional individuals will be vital for inferring the extent of gene flow among species after the separation of the gibbon genera. 相似文献
57.
据2003年9月至2005年9月,对云南中部无量山大寨子黑长臂猿种群(5个群体)进行了观察,获得了群体大小、配偶体制、繁殖间隔、环境容纳量、死亡率、灾害的发生频率等种群参数,并结合近缘种的一些相关数据,利用旋涡模型(Vortex 914),对无量山大寨子地区黑长臂猿亚种群的动态进行了模拟分析。结果显示:大寨子亚种群是一个具有很强的潜在繁殖力的种群,如果没有偷猎,亚种群在100a之内不会灭绝,并且能迅速达到环境容纳量。但是每年如果有1只成年雄性和1只成年雌性被猎杀,该种群将会在第78年灭绝,且灭绝概率为100%。不同程度的死亡率对种群影响不大,但高死亡率显著延缓了种群到达环境容纳量的时间。环境容纳量对种群遗传多样性损失具有重要的影响,在没有猎杀的情况下,种群的长期存活需要一个较大的环境容纳量。因此,在黑长臂猿受到严格保护、且栖息地主要在保护区内的今天,严密监控火灾的发生,限制牲畜进入林区等人为干扰的影响,保护好黑长臂猿栖息地是首要工作之一。但如果能使其栖息地周围的森林植被得到恢复,增加其栖息范围,将有利于该地区黑长臂猿的发展。 相似文献
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Susan G. Larson 《Evolutionary anthropology》1998,6(3):87-99
The evolutionary history of the living hominoids has remained elusive despite years of exploration and the discovery of numerous Miocene fossil ape species. Part of the difficulty can be attributed to the changing nature of our views about the course of hominoid evolution. In the 1950s and 1960s, individual Miocene taxa were commonly viewed as the direct ancestors of specific living ape species, suggesting an early divergence of the modern lineages.1–5 However, in most cases, the Miocene forms were essentially “dental apes,” resembling extant species in dental and a few cranial features, but possessing more primitive postcranial features that suggested arboreal quadrupedalism rather than suspensory habits. With the introduction of molecular methods of phylogenetic reconstruction and the increasing use of cladistic analysis, it has become apparent that the radiation leading to the modern hominoids was somewhat more recent than had been believed, and that most of the Miocene hominoid species had little to do with the evolutionary history of the living apes. © 1998 Wiley-Liss, Inc. 相似文献
60.
无量山大寨子黑长臂猿(Nomascus concolor jingdongensis)种群生存力 总被引:2,自引:0,他引:2
据2003年9月至2005年9月,对云南中部无量山大寨子黑长臂猿种群(5个群体)进行了观察,获得了群体大小、配偶体制、繁殖间隔、环境容纳量、死亡率、灾害的发生频率等种群参数,并结合近缘种的一些相关数据,利用旋涡模型(Vortex 914),对无量山大寨子地区黑长臂猿亚种群的动态进行了模拟分析。结果显示:大寨子亚种群是一个具有很强的潜在繁殖力的种群,如果没有偷猎,亚种群在100a之内不会灭绝,并且能迅速达到环境容纳量。但是每年如果有1只成年雄性和1只成年雌性被猎杀,该种群将会在第78年灭绝,且灭绝概率为100%。不同程度的死亡率对种群影响不大,但高死亡率显著延缓了种群到达环境容纳量的时间。环境容纳量对种群遗传多样性损失具有重要的影响,在没有猎杀的情况下,种群的长期存活需要一个较大的环境容纳量。因此,在黑长臂猿受到严格保护、且栖息地主要在保护区内的今天,严密监控火灾的发生,限制牲畜进入林区等人为干扰的影响,保护好黑长臂猿栖息地是首要工作之一。但如果能使其栖息地周围的森林植被得到恢复,增加其栖息范围,将有利于该地区黑长臂猿的发展。 相似文献