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81.
Gunji H Hosaka K Huffman MA Kawanaka K Matsumoto-Oda A Hamada Y Nishida T 《Primates; journal of primatology》2003,44(2):145-149
We examined bone mineral density (BMD) of the femoral neck and lumbar vertebrae of four chimpanzee skeletons from Mahale Mountains
National Park, Tanzania, and four captive ones, with a dual energy X-ray absorptiometer. The BMD of Wansombo, an old female
chimpanzee from Mahale , was remarkably lower than the mean of the other six younger adult female chimpanzees and categorized
as osteoporosis. Posture, locomotion, and trunk-sacral anatomy of chimpanzees may have prevented fractures in Wansombo, whose
BMD was below human osteoporosis criteria.
Electronic Publication 相似文献
82.
Nakamura M 《Journal of human evolution》2003,44(1):59-71
Chimpanzees (Pan troglodytes) often groom in gatherings that cannot simply be divided into unilateral dyadic grooming interactions. This feature of grooming is studied at two different levels: grooming cliques and grooming clusters. Grooming cliques are defined as directly connected configurations of grooming interactions at any given moment, and when any member of a clique successively grooms any member of another clique within 5min and within a distance of 3m, all the members of both cliques are defined as being in the same grooming cluster. Twenty-seven types of cliques are observed, with the largest one consisting of seven individuals. Mutual and/or polyadic cliques account for more than 25% of all cliques. The size of grooming clusters varies from two to 23 individuals, and almost 70% of the grooming time is spent in polyadic clusters. Although adult males groom the longest in relatively smaller clusters (size=2-4), adult females groomed the longest in clusters of five or more individuals. A review of the literature implies that mutual and polyadic cliques occur less often in other primate species than in chimpanzees. The importance of overlapping interactions for these kinds of gatherings and its possible significance in the evolution of sociality is discussed in this article. 相似文献
83.
秦岭保护区群存在的主要问题和管理对策 总被引:6,自引:0,他引:6
本文作者根据秦岭保护区群内7个自然保护区(保护站)存在的主要问题,提出了解决问题的办法。主要问题:一、牛背梁自然保护区的形状、大小、边界区划不合理;二、各自然保护区由于投资和建立时间不同,发展不平衡。三、周边地区商业采伐严重;四、农业蚕食,非法利用自然资源现象得不到制止;五、交通道路穿越保护区,影响动物基因交流;六、旅游开发缺乏统一管理。采取的对策主要是:一、在主要动物活动地带建立联合管理区和生物走廊带;二、加强对老县城自然保护区的管理和投资;三、加强对穿越保护区公路沿线的管理;四、解决对资源的过度利用,开展社区共管工作;五、对旅游实行规范化管理;六、开展多种经营创收。 相似文献
84.
山西关帝山种子植物区系研究 总被引:24,自引:5,他引:19
关帝山位于吕梁山脉中部,有种子植物737种,属于335属、85科。种子植物属种区系成分复杂多样,以温带尬发占绝对优势(温带属249属,占总属数的85.67%)。对属种区系成分和植被建群种和优势种组成的分析表明,关帝山具有典型的明温带落叶阔叶林性质。与有关山地植物区系与植被组成的比较,关帝山与太岳山具有较高的同质性和密切的联系,与太行山南部次之,而与秦岭太白山具有明显的差异。 相似文献
85.
Douglas A. Burns 《Biogeochemistry》1998,40(1):73-96
Models of the effects of atmosphericN deposition in forested watersheds have notadequately accounted for the effects of aquatic andnear-stream processes on the concentrations and loadsof NO
in surface waters. This studycompared the relative effects of aquatic andnear-stream processes with those from the terrestrialecosystem on the retention and transport ofNO
in two contrasting stream reaches ofthe Neversink River, a forested watershed in theCatskill Mountains of New York that receives among thehighest load of atmospheric N deposition in thenortheastern United States. Stream water samples werecollected every two hours and ground-water andtributary samples were collected daily at base flowconditions during four 48-hour periods from April toOctober 1992, and NO
mass balances werecalculated for each site. Results indicated diurnalvariations in stream NO
concentrations inboth reaches during all four sampling periods; this isconsistent with uptake of NO
byphotoautotrophs during daylight hours. Mass-balanceresults revealed significant stream reach losses ofNO
at both sites during all samplingperiods. The diurnal variations in NO
concentrations and the retention of NO
relative to terrestrial contributions to the streamreaches were greater downstream than upstream becausephysical factors such as the head gradients ofinflowing ground water and the organic matter contentof sediment are more favorable to uptake anddenitrification downstream. The mass retention ofNO
increased as the mean 48-hr streamdischarge increased at each site, indicating that theresponsible processes are dependent onNO
supply. Low stream temperatures duringthe April sampling period, however, probably reducedthe rate of retention processes, resulting in smallerlosses of NO
than predicted from streamdischarge alone. Water samples collected from thestream, the hyporheic zone, and the alluvial groundwater at sites in both reaches indicated that the neteffect of hyporheic processes on downstreamNO
transport ranged from conservativemixing to complete removal by denitrification. Therelative effects of biological uptake anddenitrification as retention mechanisms could not bequantified, but the results indicate that bothprocesses are significant. These results generallyconfirm that aquatic and near-stream processes causesignificant losses of NO
in the NeversinkRiver, and that the losses by these processes atdownstream locations can exceed the NO
contributions to the stream from the terrestrialenvironment during summer and fall base-flowconditions. Failure to consider these aquatic andnear-stream processes in models of watershed responseto atmospheric N deposition could result inunderestimates of the amount of NO
leaching from forested ecosystems and to an inabilityto unequivocally relate geographic differences inNO
concentrations of stream waters tocorresponding differences in terrestrial processes. 相似文献
86.
Frederick H. Sheldon David J. Lohman Haw C. Lim Fasheng Zou Steven M. Goodman Dewi M. Prawiradilaga Kevin Winker Thomas M. Braile Robert G. Moyle 《Journal of Biogeography》2009,36(6):1070-1083
Aim The oriental magpie‐robin (Copsychus saularis) of South and Southeast Asia is a phenotypically variable species that appears to be closely related to two endemic species of the western Indian Ocean: the Madagascar magpie‐robin (Copsychus albospecularis) and the Seychelles magpie‐robin (Copsychus sechellarum). This unusual distribution led us to examine evolutionary relationships in magpie‐robins, and also the taxonomic significance of their plumage variation, via a molecular phylogenetic and population genetic analysis of C. saularis and C. albospecularis. Location Southern Asia from Nepal across Indochina to southern China, and the Indian Ocean from Madagascar to the Greater Sunda and Philippine islands. Methods We sequenced 1695 nucleotides of mitochondrial DNA comprising the complete second subunit of the nicotinamide adenine dinucleotide dehydrogenase (ND2) gene and 654 bases of the cytochrome c oxidase subunit I (COI) region in 51 individuals of eight C. saularis subspecies, 10 individuals of C. albospecularis (one subspecies) and single individuals of two other Copsychus species as outgroups. The data were analysed phylogenetically, with maximum likelihood, Bayesian, relaxed clock and parsimony methods, and geographically for patterns of genetic diversity. Results Phylogenetic analysis indicated that C. albospecularis lies within the nominal C. saularis, making C. saularis polyphyletic. Malagasy and non‐Philippine Asian populations form a monophyletic group that is sister to a clade of Philippine populations. Within non‐Philippine Asian populations, two groups are evident: black‐bellied birds in the eastern Greater Sunda islands and white‐bellied birds in the western Sundas and on mainland Asia. Main conclusions The phylogeny of magpie‐robins suggests a novel pattern of dispersal and differentiation in the Old World. Ancestral magpie‐robins appear to have spread widely among islands of the Indian Ocean in the Pliocene, probably aided by their affinity for coastal habitats. Populations subsequently became isolated in island groups, notably the Philippines, Madagascar and the Greater Sundas, leading to speciation in all three areas. Isolation in the Philippines may have been aided by competitive exclusion of C. saularis from Palawan by a congener, the white‐vented shama (Copsychus niger). In the Greater Sundas, white‐bellied populations appear to have invaded Borneo and Java recently, where they hybridize with resident black‐bellied birds. 相似文献
87.
88.
Most Old World mice and rats, subfamily Murinae, have a spermatozoon with an apical hook, a long tail and, as seen typically in eutherian mammals, a bilaterally flattened head. Dramatically different from this are the sperm of the Greater Bandicoot Rat, Bandicota indica. Here, we ask the question has the structure of the sperm head co‐evolved with that of the egg coat, the zona pellucida? For this, we first summarise the morphological features of the spermatozoon of B. indica that may relate to zona pellucida penetration at the time of fertilisation, and we confirm that the sperm head is generally round, not bilaterally flattened, in profile and has a huge acrosome. We then show that the zona pellucida around oocytes in tertiary follicles also differs from that of the other murine rodents in being only about 4 μm thick and, as demonstrated by lectin staining, has an unusual abundance of alpha‐L‐fucose. These findings indicate that both the male and female gametes of this South‐East Asian murine rodent are highly divergent in their structural organisation. One of the functional implications of this probably relates to sperm–zona interactions and the release of acrosomal enzymes that probably facilitate penetration by digestion of the zona matrix at the time of fertilisation. 相似文献
89.
The potential effects of the domestic dogs (Canis familiaris) on the Endangered Ethiopian wolf (Canis simensis) through exploitative and interference competition were studied in the Web Valley of Bale Mountains national park between November 2001 and February 2003. All dogs were owned in the study area and no feral dogs were reported or observed during the research period. The diet of domestic dogs was dominated by barley husks and human faeces which contributed 45% and 20.7% of the total 382 meals observed during focal watch observations. Analysis of dog faeces provided similar results with barley husks, human faeces and animal carcasses occurring in 86.8%, 21.4% and 19.4% of the 1200 faecal samples analysed. Both focal watch and faecal analyses revealed that rodents contributed only a very small proportion of the diet of dogs accounting for only 4.2% of the focal watch and 2.8% of the faecal analysis of roaming dogs. As Ethiopian wolves fed almost exclusively on rodent year round, no significant exploitative competition between dogs and wolves were assessed. Only small proportion of the domestic dogs roamed in the Ethiopian wolf range and interference competition did not appear to be a serious threat for the Ethiopian wolf. 相似文献
90.
DOUGLAS W. SMITH EDWARD E. BANGS JOHN K. OAKLEAF CURTIS MACK JOSEPH FONTAINE DIANE BOYD MICHAEL JIMENEZ DANIEL H. PLETSCHER CARTER C. NIEMEYER THOMAS J. MEIER DANIEL R. STAHLER JAMES HOLYAN VALPHA J. ASHER DENNIS L. MURRAY 《The Journal of wildlife management》2010,74(4):620-634
Abstract: After roughly a 60-year absence, wolves (Canis lupus) immigrated (1979) and were reintroduced (1995-1996) into the northern Rocky Mountains (NRM), USA, where wolves are protected under the Endangered Species Act. The wolf recovery goal is to restore an equitably distributed metapopulation of ≥30 breeding pairs and 300 wolves in Montana, Idaho, and Wyoming, while minimizing damage to livestock; ultimately, the objective is to establish state-managed conservation programs for wolf populations in NRM. Previously, wolves were eradicated from the NRM because of excessive human killing. We used Andersen–Gill hazard models to assess biological, habitat, and anthropogenic factors contributing to current wolf mortality risk and whether federal protection was adequate to provide acceptably low hazards. We radiocollared 711 wolves in Idaho, Montana, and Wyoming (e.g., NRM region of the United States) from 1982 to 2004 and recorded 363 mortalities. Overall, annual survival rate of wolves in the recovery areas was 0.750 (95% CI = 0.728-0.772), which is generally considered adequate for wolf population sustainability and thereby allowed the NRM wolf population to increase. Contrary to our prediction, wolf mortality risk was higher in the northwest Montana (NWMT) recovery area, likely due to less abundant public land being secure wolf habitat compared to other recovery areas. In contrast, lower hazards in the Greater Yellowstone Area (GYA) and central Idaho (CID) likely were due to larger core areas that offered stronger wolf protection. We also found that wolves collared for damage management purposes (targeted sample) had substantially lower survival than those collared for monitoring purposes (representative sample) because most mortality was due to human factors (e.g., illegal take, control). This difference in survival underscores the importance of human-caused mortality in this recovering NRM population. Other factors contributing to increased mortality risk were pup and yearling age class, or dispersing status, which was related to younger age cohorts. When we included habitat variables in our analysis, we found that wolves having abundant agricultural and private land as well as livestock in their territory had higher mortality risk. Wolf survival was higher in areas with increased wolf density, implying that secure core habitat, particularly in GYA and CID, is important for wolf protection. We failed to detect changes in wolf hazards according to either gender or season. Maintaining wolves in NWMT will require greater attention to human harvest, conflict resolution, and illegal mortality than in either CID or GYA; however, if human access increases in the future in either of the latter 2 areas hazards to wolves also may increase. Indeed, because overall suitable habitat is more fragmented and the NRM has higher human access than many places where wolves roam freely and are subject to harvest (e.g., Canada and AK), monitoring of wolf vital rates, along with concomitant conservation and management strategies directed at wolves, their habitat, and humans, will be important for ensuring long-term viability of wolves in the region. 相似文献