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71.
Ecotourism involving feeding wildlife has raised public attention and is a controversial issue, especially concerning nonhuman primates. Between July 2002 and April 2005, the behavior of monkeys and tourists was collected through scan samplings, focal samplings and behavior samplings at the Shou‐Shan Nature Park located in Taiwan's second largest city—Kaohsiung. In addition, the number of tourists and monkeys was counted in different hours and places within the park. Four hundred visitors were interviewed using a questionnaire to gather data on sex, age, purpose and frequency of visit to the park. The number of tourists was significantly higher during weekends than in weekdays in all locations. Humans dominated in the initiation of interspecies interactions—the overall ratio of human‐initiated and monkey‐initiated interactions was 2.44:1. Human–monkey conflicts accounted for only 16.4% of the total interactions (n=2,166), and adult human males and adult male macaques participated in higher rates than other age/sex groups in these conflicts. Visitors showed more affiliative behavior (15.9%) than agonistic behavior (8%) toward the macaques. In response to visitors' threat or attack, the Formosan macaques mostly showed submissive behavior with bared teeth, squealed or ran away to avoid confrontation (69.1%)—only few responded with counteraggression (18.7%). This study for the first time provided evidence that food provisioning increased both the frequency and duration of aggression among Formosan macaques (P<0.001). During food provisioning, the average frequency and the duration of agonistic events of macaques were more than 4 times higher compared with those without food provisioning. The average frequency of food provision by tourists was 0.73 times/hr—more than twice the incident that monkeys grabbed the food from tourists (0.34 times/hr). If people refrain from feeding monkeys and destroying the city park's natural vegetation, monkeys can be used to educate public about nature conservation in an urban setting. Am. J. Primatol. 71:214–222, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
72.
Current genetic composition of a population is influenced by site-specific demographic history. We compared genetic diversity in two populations of Taiwanese macaques (Macaca cyclopis) with different site characteristics. Mitochondrial DNA variation in 145 individuals from one central, continuous population (Yushan) and one peripheral, isolated population (Shoushan) was ascertained by sequencing and PCR–SSCP of the 5 end hypervariable segment of the control region amplified from hair and fecal samples. All the samples from Yushan were of the same haplotype whereas those from Shoushan fell into 13 haplotypes. The mtDNA homogeneity in Yushan may indicate a local concentration of troops status of the population or the result of population bottleneck in the recent past by severe hunting. The relatively higher genetic diversity in the Shoushan population was contributed by released or escaped captive macaques. In addition, a simple method for preserving fecal sample as a DNA source is also recommended in the study.  相似文献   
73.
We investigated the energetic costs of quadrupedal and bipedal walking in two Japanese macaques. The subjects were engaged in traditional bipedal performance for years, and are extremely adept bipeds. The experiment was conducted in an airtight chamber with a gas analyzer. The subjects walked quadrupedally and bipedally at fixed velocities (<5 km/hr) on a treadmill in the chamber for 2.5-6 min. We estimated energy consumption from carbon dioxide (CO2) production. While walking bipedally, energetic expenditure increased by 30% relative to quadrupedalism in one subject, and by 20% in another younger subject. Energetic costs increased linearly with velocity in quadrupedalism and bipedalism, with bipedal/quadrupedal ratios remaining almost constant. Our experiments were relatively short in duration, and thus the observed locomotor costs may include presteady-state high values. However, there was no difference in experimental duration between bipedal and quadrupedal trials. Thus, the issue of steady state cannot cancel the difference in energetic costs. Furthermore, we observed that switching of locomotor mode (quadrupedalism to bipedalism) during a session resulted in a significant increase of CO2 production. Taylor and Rowntree ([1973] Science 179:186-187) noted that the energetic costs for bipedal and quadrupedal walking were the same in chimpanzees and capuchin monkeys. Although the reason for this inconsistency is not clear, species-specific differences should be considered regarding bipedal locomotor energetics among nonhuman primates. Extra costs for bipedalism may not be great in these macaques. Indeed, it is known that suspensory locomotion in Ateles consumes 1.3-1.4 times as much energy relative to quadrupedal progression. This excess ratio surpasses the bipedal/quadrupedal energetic ratios in these macaques.  相似文献   
74.
Acidic mammalian chitinase (AMCase), an enzyme implicated in the pathology of asthma, is capable of chitin cleavage at a low pH optimum. The corresponding gene (CHIA) can be found in genome databases of a variety of mammals, but the enzyme properties of only the human and mouse proteins were extensively studied. We wanted to compare enzymes of closely related species, such as humans and macaques. In our attempt to study macaque AMCase, we searched for CHIA-like genes in human and macaque genomes. We found that both genomes contain several additional CHIA-like sequences. In humans, CHIA-L1 (hCHIA-L1) is an apparent pseudogene and has the highest homology to CHIA. To determine which of the two genes is functional in monkeys, we assessed their tissue expression levels. In our experiments, CHIA-L1 expression was not detected in human stomach tissue, while CHIA was expressed at high levels. However, in the cynomolgus macaque stomach tissue, the expression pattern of these two genes was reversed: CHIA-L1 was expressed at high levels and CHIA was undetectable. We hypothesized that in macaques CHIA-L1 (mCHIA-L1), and not CHIA, is a gene encoding an acidic chitinase, and cloned it, using the sequence of human CHIA-L1 as a guide for the primer design. We named the new enzyme MACase (Macaca Acidic Chitinase) to emphasize its differences from AMCase. MACase shares a similar tissue expression pattern and pH optimum with human AMCase, but is 50 times more active in our enzymatic activity assay. DNA sequence of the mCHIA-L1 has higher percentage identity to the human pseudogene hCHIA-L1 (91.7%) than to hCHIA (84%). Our results suggest alternate evolutionary paths for human and monkey acidic chitinases.  相似文献   
75.
We describe a restriction analysis that distinguishes between rhesus macaques of unmixed Indian and Chinese ancestry and between western and eastern Chinese ancestry. We amplified a 254-bp fragment of mitochondrial DNA (mtDNA) that contains restriction sites hypothesized to be diagnostic of country of origin for samples from 534 and 567 individuals alleged to be of solely Indian or solely Chinese origin, respectively. After digestion with the MaeIII, SmlI, and BccI restriction enzymes, the polymerase chain reaction (PCR) products of only 3 of the 1101 samples exhibited restriction patterns uncharacteristic of their alleged country of origin. A sample comprising 392 of these rhesus macaques was genotyped for 24 nuclear microsatellite (STR) loci. Principal coordinates analysis confirmed marked genetic similarity of regional populations within each country but a substantial difference between Indian and Chinese rhesus macaques. Using STRUCTURE (Pritchard and Wen, 2003),we assigned probabilities of Chinese and Indian ancestry to each sample based on its STR genotypes. We assigned all the unmixed rhesus macaques to their correct countries of origin with probabilities >0.95. We constructed an artificial sample of 1st-generation hybrid Indian/Chinese rhesus macaques by randomly sampling from the genotypes of Indian and Chinese individuals. STRUCTURE assigned robabilities of Chinese and Indian ancestry to hybrids that closely corresponded with the proportions of alleles in that sample drawn from unmixed Chinese and Indian rhesus macaques.  相似文献   
76.
The stable isotopic composition of drinking water, diet, and atmospheric oxygen influence the isotopic composition of body water ((2)H/(1)H, (18)O/(16)O expressed as δ(2) H and δ(18)O). In turn, body water influences the isotopic composition of organic matter in tissues, such as hair and teeth, which are often used to reconstruct historical dietary and movement patterns of animals and humans. Here, we used a nonhuman primate system (Macaca fascicularis) to test the robustness of two different mechanistic stable isotope models: a model to predict the δ(2)H and δ(18)O values of body water and a second model to predict the δ(2)H and δ(18)O values of hair. In contrast to previous human-based studies, use of nonhuman primates fed controlled diets allowed us to further constrain model parameter values and evaluate model predictions. Both models reliably predicted the δ(2)H and δ(18)O values of body water and of hair. Moreover, the isotope data allowed us to better quantify values for two critical variables in the models: the δ(2)H and δ(18)O values of gut water and the (18)O isotope fractionation associated with a carbonyl oxygen-water interaction in the gut (α(ow)). Our modeling efforts indicated that better predictions for body water and hair isotope values were achieved by making the isotopic composition of gut water approached that of body water. Additionally, the value of α(ow) was 1.0164, in close agreement with the only other previously measured observation (microbial spore cell walls), suggesting robustness of this fractionation factor across different biological systems.  相似文献   
77.
78.
BACKGROUND: Agnathia is a rare malformation characterized by the absence of the mandible. METHODS: A male rhesus monkey with malformations was found dead and studied by internal examination, radiographs and histopathology. RESULTS: A case of a rare first branchial arch anomaly with agenesis of the mandible and tongue is presented. The animal also had visceral deformities. However, ears were normal in shape and only slightly low in position. The craniofacial malformations may reflect incomplete separation of the first branchial arch into its maxillary and mandibular processes. CONCLUSIONS: The association between the craniofacial and other corporal anomalies is unclear.  相似文献   
79.
2007年3~5月,采用随机取样法对黄山短尾猴(Macaca thibetana)YA1群架桥行为进行研究。结果表明,不同时间段架桥行为发生次数存在极显著差异(t=3.912,df=10,P<0.01)。成年组雄性个体是主要发起者(Z=-2.1888,P<0.05)和接受者(Z=-2.5238,P<0.05),但同年龄组不同性别个体发起次数(Z=-1.755,P>0.05)无显著差异,接受次数(Z=-2.201,P<0.05)差异显著。架桥行为多采用雄性婴幼猴(Z=-2.437,P<0.05)(F=6.735,df=2,P<0.05)作为媒介,母亲序位影响婴幼猴在架桥中被使用的次数(Z=-3.724,P<0.01)。不同序位雄性(F=2.947,df=4,P<0.05)和雌性个体(F=5.320,df=4,P<0.05)架桥行为发起模式主要是第Ⅰ类。雌性个体选择具有亲缘关系的个体作为架桥媒介(Z=-2.490,P<0.05),但雄性个体对母系亲属后代无明显选择性(Z=-0.866,P>0.05)。短期研究表明,黄山短尾猴社群中的架桥行为主要采用第Ⅰ类模式;亲缘关系不一定是影响架桥行为媒介选择的主要因素;架桥行为具有缓解群体间竞争压力的作用。  相似文献   
80.
恒河猴群微卫星DNA多态性的分析   总被引:9,自引:2,他引:7  
目的 确立一种对恒河猴群个体的遗传物质进行准确可靠、快速简便的遗传检测方法。方法 利用聚合酶链反应 (PCR)扩增技术对 2 0只恒河猴群个体间进行了DNA多态性的分析。结果 筛选出 9个微卫星DNA位点具有显著多态性 ,4个微卫星DNA位点没有多态性 ,还有 2个位点等位基因数目较少。结论 利用这些多态性微卫星位点建立一种对恒河猴群个体进行有效、准备可靠、快捷简便的遗传背景监测方法。  相似文献   
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