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1.
The drill monkey has been shown by serology and PCR to harbor a unique simian immunodeficiency virus (SIVdrl). A pol sequence, amplified from uncultured peripheral blood cells, is most closely related to the equivalent SIV sequences from the red-capped mangabey (SIVrcm), the sabaeus African green monkey (SIVagmSAB), and the chimpanzee (SIVcpz) and to the human immunodeficiency virus type 1 (HIV-1) sequence of humans. It is as yet unclear whether SIVdrl has a mosaic genome like SIVrcm and SIVagmSAB, is a member of the SIVcpz/HIV-1 lineage, or represents a novel primate lentivirus lineage.  相似文献   

2.
Very little information is available on the current status of drill populations in Cameroon. We report on drill group sizes and status in Bakossiland, a mountainous area spanning 2000 km2 in the Littoral and South West Provinces of southwestern Cameroon. Between 1970 and 2002 direct visual counts of drill groups (n = 105) yielded group size estimates ranging from 5 to 400 (mean ± S.E.M.; 93.1 ± 8.4). We encountered solitary adult male drills on 8 occasions. Groups were at all elevations (150–2000 m) in 5 habitat types: lowland, premontane, submontane and montane forests and montane savannah at 2000 m). Group sizes did not vary with respect to elevation, habitat type or season (wet and dry mo). However, over the past decade drills have been virtually hunted out of the Mwenzekong Mountains (Banyang Mbo Wildlife Sanctuary), and they are greatly reduced in the southern Bakossi forests of Mwendolengo, Edib Hills and Mungo River. The species became extinct in the Loum Forest Reserve in the late 1970s, and until recently was thought to have become extinct on Mount Mwanenguba. Since 1994 on Mount Kupe, the drill population has begun to recover, largely due to protection afforded by the Bakossi traditional chiefs. Traditional powers and values are still influential in the region. A new national park—Bakossi Mountains National Park— and associated Protected Areas are currently under gazettment. We discuss the effectiveness of conservation strategies in relation to the survival of drills in the area.  相似文献   

3.
4.
Since simian immunodeficiency virus (SIV) was found to be the source of the human AIDS pandemic, a major goal has been to characterize the diversity of SIV strains in the wild and to assess their potential for crossover into humans. In the present study, SIV was isolated from a seropositive drill (Mandrillus leucophaeus) and three seropositive mandrills (Mandrillus sphinx) by using macaque peripheral blood mononuclear cells (PBMC). Full-length sequences were obtained from a drill and mandrill and designated SIVdrl1FAO and SIVmnd5440, respectively. A 182-bp fragment of the pol genes of the two remaining mandrill SIV isolates was also analyzed. Phylogenetic analyses demonstrated that SIVdrl1FAO formed a monophyletic clade with SIVmnd5440 and SIVmndM14, recently designated SIVmnd type 2. Both the SIVdrl and SIVmnd type 2 genomes carried a vpx gene and appeared to share a common ancestor with SIVrcm in the 5' region of the genome and with SIVmndGB1 (type 1) in the 3' region of the genome. A statistically significant recombination breakpoint was detected at the beginning of envelope, suggesting that the viruses were descendents of the same recombinant. Phylogenetic analysis of vpx and vpr genes demonstrated that the vpx genes formed a monophyletic cluster that grouped with vpr from SIVagm. In addition, both SIVdrl1FAO and SIVmnd5440 replicated in human PBMC and therefore could pose a risk of transmission to the human population.  相似文献   

5.
The drill (Mandrillus leucophaeus), a forest-living Old World monkey, is highly sexually dimorphic, with males exhibiting extreme secondary sexual characteristics, including growth of paranasal swellings on the muzzle. In this study, the size of the secondary bone that forms the paranasal swellings on the muzzles of drills was assessed in relation to body mass proxies. The relationship between the overall size of the muzzle and surrogate measures of body mass was also examined. In female drills, muzzle breadth was positively correlated with two proxies of overall body mass, greatest skull length and upper M1 area. However, there was no such correlation in males. Paranasal swellings in males also appeared to have no significant relationship to body mass proxies. This suggests that secondary bone growth on the muzzles of male drills is independent of overall body size. Furthermore, this secondary bone appears to be vermiculate, probably developing rapidly and in an irregular manner, with no correlation in the sizes of paranasal swelling height and breadth. However, various paranasal swelling dimensions were related to the size of the muzzle. It is suggested that the growth of the paranasal swellings and possibly the muzzle could be influenced by androgen production and reflect testes size and sperm motility. The size and appearance of the paranasal swellings may thus be an indicator of reproductive quality both to potential mates and male competitors. Further work is required to investigate the importance of the paranasal swellings as secondary sexual characteristics in Mandrillus and the relationship between body size and secondary sexual characteristics. Attention should also be paid to the mechanisms and trajectories of facial growth in Mandrillus.  相似文献   

6.
A field study of mandrill was carried out from 1979 to 1983 in Cameroon for 27 months. Group size of mandrills ranged from 15 to 95 and composition was estimated by direct and indirect observations. The ratio of group size to one adult male was 13.9, larger than other baboon species except the drill. Solitary males were seen. The mandrill may have two types of groups: one-male and multi-male. The multi-male group was observed to split into subgroups, one of which was sometimes a one-male group. The multi-male subgroup was assumed to be composed of several one-male groups. The home range area of mandrills was estimated to be at least 5 km5 to 28 km2. Their large home range size could be related to their characteristic feeding pattern in the forest.  相似文献   

7.
A field study on the ecology of mandrills (Mandrillus sphinx) was carried out for 28 months in Cameroon. Fresh food remnants and large quantities of fresh feces were collected by following the groups. Analyses of these products indicated that fruit (including seeds), monocotyledonous plant leaves and insects (especially ants and termites), were frequently eaten. Mandrills mostly ate the plant and animal foods in the lower forest stratum and on the ground. Fallen seeds and monocotyledonous plant leaves were eaten more frequently in the minor fruiting season than in the major fruiting season presumably to compensate for the shortage of fresh fruit during the former. Daily travel distances were shorter during the minor fruiting season than during the major fruiting season, because in the minor fruiting season mandrills forage for small food items, such as the new leaves and piths of monocotyledons and fallen seeds which are sparsely distributed on the ground, while in the major fruiting season they search for widely distributed food such as fruit. The daily pattern of group movement and a food intake experiment suggest that mandrills move and feed continuously throughout the day. Use of fallen seeds and monocotyledonous plant leaves appears to enable mandrills to maintain a terrestrial life in the tropical rain forest. The feeding and ranging characteristics of mandrills are basically similar to those of other baboon species in open land, though their environments differ extremely.  相似文献   

8.
Where individuals contest access to a resource, escalated physical fighting presents a risk to all involved. The requirement for mechanisms of conflict management has led to the evolution of a variety of decision rules and signals that act to reduce the frequency of aggression during competitive encounters. We examined strategies of conflict management in male mandrills (Mandrillus sphinx) living in two semi‐free‐ranging groups in Gabon. Adult male mandrills are large (31 kg), with long canines, making the costs of conflict potentially very high. We found that males formed dominance hierarchies, but that male–male relationships were characterized by avoidance, appeasement and ignoring. Fights were rare, but could result in death. Examination of the relationship between dominance and signaling showed that males use facial and gestural signals to communicate dominance and subordinance, avoiding escalated conflict. Male mandrills also possess rank‐dependent red coloration on the face, rump and genitalia, and we examined the hypothesis that this coloration acts as a ‘badge of status’, communicating male fighting ability to other males. If this is the case, then similarity in color should lead to higher dyadic rates of aggression, while males that differ markedly should resolve encounters quickly, with the paler individual retreating. Indeed, appeasement (the ‘grin’ display), threats, fights and tense ‘stand‐off’ encounters were significantly more frequent between similarly colored males, while clear submission was more frequent where color differences were large. We conclude that male mandrills employ both formal behavioral indicators of dominance and of subordination, and may also use relative brightness of red coloration to facilitate the assessment of individual differences in fighting ability, thereby regulating the degree of costly, escalated conflict between well‐armed males.  相似文献   

9.
Spontaneous diabetes mellitus was reported in a Mandrillus leucophaeus (drill baboon) and a Mpacaca cyclopis (Formosan rock macaque). Each had hyperglycemia, impaired clearance of glucose during tolerance test, and reduced concentrations of immunoreactive insulin; the M cyclopis also had increased triglyceride and prebetalipoprotein concentrations. Both monkeys had extensive amyloid infiltration into the islets of Langerhans and loss of beta cells. Beta cell obliteration can account for the appearance of the diabetic syndrome in these and other nonhuman primate species.  相似文献   

10.
The complete primary structure of the hemoglobin from the Mandrill (Mandrillus sphinx, Primates) is presented. This hemoglobin comprises two components in approximately equal amounts (HB I and Hb II). The alpha-chains differ in positions 5 (A3) and 9 (A7) having Ala and Asn in the alpha I-chains and Asp and His in the alpha II-chains. The beta-chains are identical. The components could be separated by DEAE-Sephacel chromatography. The globin chains were obtained by carboxymethylcellulose chromatography or high-performance liquid chromatography. The sequences were established by automatic liquid or gas phase Edman degradation of the chains and their tryptic peptides. The alpha-chains show 9 and 11 and the beta-chains 8 exchanges compared with the corresponding human chains, respectively. In the beta-chains one alpha 1/beta 1- and one alpha 1/beta 2-contact is substituted. A comparison of the primary structures of the Mandrill hemoglobin chains with those of other species of the Cercopithecidae family shows that Mandrillus sphinx should be placed between Cercopithecus and Macaca on one side and Papio, Theropithecus and Cercocebus on the other.  相似文献   

11.
We present an annotated checklist for a total 241 reptiles and 22 amphibians including 5 frogs, 9 toads, 7 newts and salamanders, 1 crocodile, 1 worm lizard, 148 lizards, 79 snakes and 12 turtles and tortoises, includes the most scientific literature up to August 2014 and also based on several field surveys conducted in different Provinces of Iran from 2009 to 2014. We present an up-to-dated checklist of reptiles and amphibians in Iran. We provide a comprehensive listing of taxonomy, names, distribution and conservation status of all amphibians and reptiles of Iran. This checklist includes all recognized named taxa, English names for classes, orders, families, species, subspecies along with Persian names for species, including indication of native and introduced species. For the first time we report two non-native introduced reptiles from natural habitats of Iran. Of the total 22 species of amphibians in Iran, 6(27.2%) are endemic and of the total 241 species of reptiles, 55(22.8%) are endemic. Of the 22 amphibians species in Iran, 3(13%) are Critically Endangered, 2(9%) are Vulnerable and of the 241 reptile species 3(1.2%) are Critically Endangered, 4(1.6%) are Endangered and 10(4.1%) are Vulnerable. Accordingly, this paper combines significant aspects of taxonomy, common names, conservation status and distribution of the Iranian herpetofauna.  相似文献   

12.
Thomas, D.H.L., Anders, S. & Penn, N.J. 2000. Conservation in the community: the Kilum-Ijim Forest Project, Cameroon. Ostrich 71 (1 & 2): 157–161.

BirdLife International has worked for ten years in Cameroon's North-West Province to assist the local people and government of Cameroon in achieving the conservation and sutainable management of the last significant remnant of a unique montane forest ecosystem. The Kilum/Ijim forests are almost certainly the last remaining habitat for the conservation of two endemic and threatened bird species, Bannerman's Turaco Tauraco bannermani and Banded Wattle-eye Platytiera laticincta. The forests have no legal designation as formal protected areas but have been conserved through local concern and knowledge of the multiple values of an intact forest ecosystem, backed up by the enforcement of traditional regulations, and support from the project to finding solutions to peoples' land use and natural resource management needs within and outside the forests. The project is now working under the umbrella of a national Biodiversity Conservation and Management Programme in Cameroon, funded by the Global Environment Facility, to establish the Kilum/Ijirn as the first community-managed forest in the country. A brief history and background to the project is presented, with emphasis on lessons learned by BiraLife and the success of current efforts to achieve the conservation of the forests through community management. The issues are discussed in the general context of an integrated conservation and development programme (ICDP).  相似文献   

13.
2012年11月至2013年7月间研究了独龙江乡区域羚牛指名亚种Budorcas taxicolor taxicolor(后文简称羚牛)的种群分布、数量和保护现状的问题。研究采用了改良的访问调查和实地调查相结合的方法。其中实地调查独龙江乡羚牛种群一群,调查面积35.70 km2,目测羚牛种群数量58头,适宜生境面积24.46 km2。计算羚牛适宜生境种群密度为2.4头/km2。种群数量和访查信息相符合,说明采用访问调查的方法是可靠的。本研究共计访问调查了独龙江乡的25个村庄,发现共有12个羚牛种群分布在独龙江乡,分布区羚牛适宜生境面积总和为167 km2。综合羚牛分布区面积和访查结果,本研究估算当前独龙江羚牛种群数量为400~450头。根据实地调查中羚牛利用的生境类型,利用GIS分析获得全独龙江羚牛适宜生境面积为1726 km2,可承载超过4000头,因此独龙江区域应为羚牛指名亚种的主要分布区。基于访查结果本研究还分析了羚牛的垂直分布和保护现状,提出降低人为干扰和保护羚牛生境廊道是独龙江羚牛保护的关键。  相似文献   

14.
15.
Trigonobalanus doichangensis is a national rare and endangered plant of China. It is restricted to 4 sites in southwest Yunnan, China and 1 site in Chiang-Rai, northern Thailand. Investigations revealed that 4 community types are currently extant in Yunnan: isolated individuals, sprouting woods, mono-dominant forest and co-dominant forest. The habitats have been severely damaged and the populations there are facing a high risk of extinction. The adult phase of T. doichangensis is reached when a tree attains a height of about 4 m. The flowering and fruiting time varies slightly among populations and/or across the micro-habitats. In comparison with other fagaceous plants in the community, T. doichangensis has an inverse flowering and fruiting period from October through to May. Although microspore genesis and the development of male gametes are normal, the pollen does not germinate until at least 8 h culture. The highest germination rate was 37.8%. In addition, only 9.8% of the nuts contain well-developed seeds. Genetic variation analyzed with random amplified polymorphic DNA indicated that its total genetic diversity was 0.1600 and genetic diversity within populations was 0.0749, the coefficient of gene differentiation was 0.5320. Therefore, T. doichangensis has high genetic differentiation, a low level of genetic diversity and a poor gene flow compared to the other fagaceous species. It seems that habitat degradation, over exploitation and reproductive barriers, are most likely to be the factors threatening the species. However, it may be a combination of geographical catastrophic events, habitat deterioration, declining genetic diversity and physiological stress. Therefore, a practical conservation strategy for T. doichangensis is urgently needed. #Supported by the important directional item of the Chinese Academy of Sciences (KSCX2-SW-104)  相似文献   

16.
17.
中华穿山甲的研究及保护现状   总被引:5,自引:0,他引:5  
通过查阅中华穿山甲Manis pentadactyla研究的文献,从形态分类学、生态学、遗传学几方面综述了中华穿山甲的研究现状.结合当前中华穿山甲的研究状况,建议应加强和深入其相关领域的基础研究工作,以此来澄清其分类地位问题,提供其资源保护的有效的科学理论依据和解决其资源保护与利用的矛盾问题.  相似文献   

18.
A recent systematic survey program of protected areas in Laos documented douc langurs (Pygathrix nemaeus) widely between 14°25N and 18°38N. Their precise northern limit is unclear as security constraints prevented survey there, but the species is unlikely to occur in Laos north of 20°. All our records are of the nominate, red-shanked form, P. n. nemaeus, though in the far south, greatly reduced red on the legs suggests intergradation with another form. Our records are overwhelmingly from evergreen or semievergreen forest and from a wide altitudinal range (200–1600 m). In most sites habitat was little degraded, but whether this reflects choice for such habitats, or the generally lower hunting pressure within them, is unclear. The largest population occurs over 3000 km 2 of the Nam Theun basin and surroundings, encompassing the protected areas of Nakai-Nam Theun, Hin Namno and the proposed Nam Theun Extension. This is the most important population of red-shanked langurs in the world. Laos supports globally the vast majority of their conservable population. Douc langurs are threatened in Laos by habitat fragmentation increasing their vulnerability to the existing high hunting levels. They are a favored target for local consumption and for local and Vietnamese hunters and traders. Protective measures should center around implementing habitat conservation and antihunting measures in the recently-declared National Biodiversity Conservation Areas. A recent government initiative to reduce gun use in rural areas is likely to have a strong positive effect on the population. The best protection for some time will remain the inaccessibility of their habitat. Accordingly, road-building into remote forest and piecemeal clearance at its edges should thus be minimized. Cross-border attention should be given to wildlife trading, including measures to reduce market demand.  相似文献   

19.
Male primates that attempt to monopolize access to receptive females by mate‐guarding expend time and energy and risk injury, making reproduction costly. Males should therefore show mate choice and preferentially allocate mating effort to females that are likely to be fertile and those that will produce high‐quality offspring. Specifically, males should preferentially mate‐guard high‐ranking females rather than low‐ranking females, as such females are more likely to be fertile and are able to invest more in offspring. Males should also prefer parous females to nullipares, for similar reasons. Finally, males should avoid mating with close relatives, to avoid the deleterious effects of inbreeding. We investigated 13 group‐years of mate‐guarding observations for two semi‐free‐ranging groups of mandrills to examine the influence of these factors on male investment in mate‐guarding. We found that males mate‐guarded higher‐ranking females more than lower‐ranking females, and parous females more than nullipares. Female age, true relatedness and maternal kinship did not influence male mate‐guarding. Our results suggest that male mandrills do exercise mate choice for higher‐quality females, in the form of higher‐ranking and parous females. As alpha males are responsible for the great majority of mate‐guarding, this can lead to assortative mating, where high‐ranking males reproduce with high‐ranking females, and has important implications for social relationships and kin selection.  相似文献   

20.
Sexual selection theory explains the evolution of exaggerated male morphologies and weaponry, but the fitness consequences of developmental and age-related changes in these features remain poorly understood. This long-term study of mandrill monkeys (Mandrillus sphinx) demonstrates how age-related changes in canine tooth weaponry and adult canine size correlate closely with male lifetime reproductive success. Combining long-term demographic and morphometric data reveals that male fitness covaries simply and directly with canine ontogeny, adult maximum size, and wear. However, fitness is largely independent of other somatometrics. Male mandrills sire offspring almost exclusively when their canines exceed approximately 30 mm, or two-thirds of average adult value (45 mm). Moreover, sires have larger canines than nonsires. The tooth diminishes through wear as animals age, corresponding with, and perhaps influencing, reproductive senescence. These factors combine to constrain male reproductive opportunities to a brief timespan, defined by the period of maximum canine length. Sexually-selected weaponry, especially when it is nonrenewable like the primate canine tooth, is intimately tied to the male life course. Our analyses of this extremely dimorphic species indicate that sexual selection is closely intertwined with growth, development, and aging, pointing to new directions for sexual selection theory. Moreover, the primate canine tooth has potential as a simple mammalian system for testing genetically-based models of aging. Finally, the tooth may record details of life histories in fossil primates, especially when sexual selection has played a role in the evolution of dimorphism.  相似文献   

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