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PubMed2007

Copulation behavior within one-male groups of wild Rhinopithecus roxellana in the Qinling Mountains of China.

This study was conducted using focal animal sampling on the west ridge group of the Sichuan snub-nosed monkey (Rhinopithecus roxellana) located in the Zhouzhi National Nature Reserve on the north slope of the Qinling Mountains, from 8 July 2003 to 24 May 2004. The difference in the average frequency of copulations for each focal male for each month was significant (F=3.068, P=0.016, one-way ANOVA test) with the majority of copulations occurring between September and November. Duration of intromission ranged from 2 to 39 s, with a mean of 16.0+/-0.4 s. Females initiated 627 courtship attempts (96.2%), while males only initiated 3.8%. Both adult females (72.8%) and sub-adult females (27.2%) were involved in sexual interference acts. Females who gave birth in 2004 performed more sexual interference acts than would be expected by chance in the reproductive period of 2003 (X2=13.73>X2(0.005,2), df=2, P<0.005). Male response to female interference was equally divided into "solicitor mounting" and "interrupter mounting". The resident males of one-male units were not observed to mount both the solicitor and the interrupter or mount neither following female solicitation interruptions. Three post-conception copulations were also observed in this study. These results suggest a skewed sexual competition, with multiple females competing for a single male, which was shown by courtship attempts and female interference.

Altitude↗
PubMed1997

A family of repetitive DNA sequences in Old World primates.

A dispersed family of repetitive DNA sequences that is amplified in Old World primates has been characterized. The sequences are present in about 250-350 copies in humans, found on all chromosomes, and some are at least 1 kb in size. Within the core repeat is a 178-bp region that is moderately-to-highly conserved. A representative sequence exhibited strong promoter activity when placed in front of a promoterless gene and transfected into human cells. This promoter activity has been localized to a 138-bp region of the repeat that is about 150 bp downstream of the 178-bp conserved region. Transcripts of the sequences were not detected in six human breast epithelial and teratocarcinoma cell lines. Based upon the work of Pavelitz et al. [Pavelitz, T., Rusche, L., Matera, A.G., Scharf, J.M., Weiner, A.M., 1995. EMBO J. 14, 169-177], the sequence appears to be related to the LTR of an HERV-K class human endogenous retrovirus.

Animals↗
PubMed2004

Metric sexual dimorphism in the deciduous teeth of Old World monkeys.

Metric variability of the deciduous teeth of several Old World monkey taxa were examined at the intergeneric and interspecific taxonomic levels. In general, the deciduous teeth of these taxa lack significant size sexual dimorphism with the exception of Papio cynocephalus. The data clearly demonstrate that male dimensions are not consistently larger than those of the females, in fact, female dimensions are frequently larger than those of the male. Thus, negative percentage sexual dimorphism is present in all species except Papio cynocephalus. Tooth size differences are randomly distributed among these species and do not appear to have any anatomical significance with respect to the different diets of the colobine and cercopithecine monkeys. This odontometric analysis reveals that it would be problematical to use deciduous tooth size as a basis for species identification with the possible exception of Papio cynocephalus.

Animals↗
PubMed2005

Insights into the epidemiology and genetic make-up of Oesophagostomum bifurcum from human and non-human primates using molecular tools.

The nodule worm Oesophagostomum bifurcum (Nematoda: Strongylida) is a parasite of major human health importance predominantly in northern Togo and Ghana. Currently, it is estimated that 0.25 million people are infected with this nematode, and at least 1 million people are at risk of infection. Infection with this parasite causes significant disease as a consequence of encysted larvae in the wall of the large intestine. In spite of the health problems caused by O. bifurcum, there have been significant gaps in the knowledge of the biology, transmission and population genetics of the parasite. This review provides an account of some recent insights into the epidemiology and genetics of the parasite from human and non-human primate hosts in specific regions of Africa using molecular tools. Recent research findings are discussed mainly in relation to non-human primates being reservoirs of infection, and the consequences for the prevention and control of oesophagostomiasis in humans are briefly discussed.

Animals↗
PubMed2001

Ecological importance of trichromatic vision to primates.

Trichromatic colour vision, characterized by three retinal photopigments tuned to peak wavelengths of approximately 430 nm, approximately 535 nm and approximately 562 nm (refs 1, 2), has evolved convergently in catarrhine primates and one genus of New World monkey, the howlers (genus Alouatta). This uniform capacity to discriminate red-green colours, which is not found in other mammals, has been proposed as advantageous for the long-range detection of either ripe fruits or young leaves (which frequently flush red in the tropics) against a background of mature foliage. Here we show that four trichromatic primate species in Kibale Forest, Uganda, eat leaves that are colour discriminated only by red-greenness, a colour axis correlated with high protein levels and low toughness. Despite their divergent digestive systems, these primates have no significant interspecific differences in leaf colour selection. In contrast, eaten fruits were generally discriminated from mature leaves on both red-green and yellow-blue channels and also by their luminance, with a significant difference between chimpanzees and monkeys in fruit colour choice. Our results implicate leaf consumption, a critical food resource when fruit is scarce, as having unique value in maintaining trichromacy in catarrhines.

Adaptation, Biological↗
PubMed2006

Parallel adaptive origins of digestive RNases in Asian and African leaf monkeys.

Similar morphological or physiological changes occurring in multiple evolutionary lineages are not uncommon. Such parallel changes are believed to be adaptive, because a complex character is unlikely to originate more than once by chance. However, the occurrence of adaptive parallel amino acid substitutions is debated. Here I propose four requirements for establishing adaptive parallel evolution at the protein sequence level and use these criteria to demonstrate such a case. I report that the gene encoding pancreatic ribonuclease was duplicated independently in Asian and African leaf-eating monkeys. Statistical analyses of DNA sequences, functional assays of reconstructed ancestral proteins and site-directed mutagenesis show that the new genes acquired enhanced digestive efficiencies through parallel amino acid replacements driven by darwinian selection. They also lost a non-digestive function independently, under a relaxed selective constraint. These results demonstrate that despite the overall stochasticity, even molecular evolution has a certain degree of repeatability and predictability under the pressures of natural selection.

Adaptation, Physiological↗
PubMed1986

Four generations of probable person-to-person transmission of human monkeypox.

This paper examines an outbreak of five cases of human monkeypox which occurred in children belonging to two families living in the West Kasai region of Zaire during May-July 1983. Epidemiologic investigations suggest that the first case was infected from an animal source, possibly a monkey, and that each of the other four cases was infected from a previous human case. Three of these cases of presumed person-to-person transmission occurred in close household contacts. The other case infection occurred either by casual contact within the hospital compound, or possibly because of infection due to use of the same syringe for injections. Human monkeypox is the most important orthopoxvirus infection in the post-smallpox eradication period. The disease is a zoonosis and person-to-person transmission is rather difficult. Thus, this episode is a rare event and special analysis of the circumstances is discussed. However, it supports the necessity to carry out surveillance and research on this disease as recently reported by Arita et al.

Animals↗
PubMed1994

Spontaneously occurring fractures of the spine in skeletally immature animals.

STUDY DESIGN: Twelve spontaneously occurring fractures of the spin in nine skeletally immature animals were investigated. OBJECTIVES: These fractures were analyzed radiographically, morphologically, and histologically. SUMMARY OF BACKGROUND DATA: The most commonly injured regions were the cervical and lumbar regions. Multiple-level fractures were noted in three specimens. METHODS: Morphologic and histologic examination invariably detected fractures in cases of spinal cord injury without radiographic abnormality. RESULTS: The end-plate physes and synchondroses were found to be the "weak links" for propagation of fractures. Radiographically benign-appearing ring apophyseal fractures were found histologically to propagate from the end-plate physis through the vertebral body via the contiguous neurocentral synchondroses. CONCLUSIONS: The observed morphologic and histologic fracture patterns should provide a better understanding of the probable comparable pathoanatomy of spine and spinal cord injuries in children.

Animals↗
PubMed1996

Tumors of the respiratory tract observed at the German Primate Center, 1978-1994.

Eight spontaneous pulmonary tumors (four bronchiolar tubular adenomas, two bronchiolar adenocarcinomas, two squamous-cell carcinomas) occurred in a total of 54 adult tree shrews (Tupaia belangeri) of the GPC colonies between 1978 and 1994. The adenomas and adenocarcinomas consisted of tubularly or trabecularly arranged cuboidal to cylindrical cells interspersed with some PAS-positive goblet cells, thus resembling the epithelial lining of respiratory bronchioles of tree shrews. The two squamous-cell carcinomas probably originated from the pulmonary alveoles. Three more pulmonary tumors (one small-cell carcinoma, one bronchial adenoma, one squamous-cell carcinoma) developed in 409 adult callitrichids of the GPC colonies during the same period, and one more bronchial adenoma was observed in a common marmoset (Callithrix jacchus) of another colony located in Göttingen. With regard to the adenomas and squamous-cell carcinomas, a similar cellular origin with the three shrews is assumed. The small-cell carcinoma possibly developed from the bronchial epithelium, provided a pathogenesis parallel to that of human small-cell carcinoma is suggested. Four of the tree shrew pulmonary adenomas/adenocarcinomas and the small-cell Ca were macroscopically visible as yellowish-grey nodules of 1 mm x 1 mm to 15 mm x 15 mm diameter, predominantly involving the main lobes (2 x right main lobes, 2 x left main lobes, 1 x all lobes). The pulmonary tumors of the other animals were below macroscopical detectability.

Adenocarcinoma↗
PubMed1975

Osteometric shape relationships in the wrist joint of some anthropoids.

Multivariate morphometric analyses of the wrist morphology of monkeys, apes and humans indicated that there is a fundamental difference between cercopithecoids and hominoids which can be related to functional and behavioral differences. The wrists of the Miocene fossil hominoids (Dryopithecus africanus and Pliopithecus vindobonensis) are almost completely monkey-like in their structure.

Alouatta↗
PubMed1979

The primates in Darfur, Republic of Sudan.

The paper describes the distribution, group size and relative abundance of Erythrocebus patas and Papio doguera in Darfur Province, Sudan. Less detailed information is given on Cercopithecus aethiops and Galago senegalensis. Detailed observations were carried out in the field and by low-level aerial survey during 1972--1978 and have been supplemented by references to the literature where appropriate.

Animals↗
PubMed1980

Polyspecific associations of Cercocebus albigena: geographic variation and ecological correlates.

The characteristics of mixed-species groups and interspecific interactions involving the mangabey, Cercocebus albigena, are described. Polyspecific associations are common and behaviorally complex. In Uganda, ecological data suggest that associations with some species are related to foraging, although evidence that these associations benefit the individuals involved remains equivocal. West African data indicate considerable geographic variability in polyspecific association tendencies.

Aggression↗
PubMed1986

New wrist bones of Proconsul africanus and P. nyanzae from Rusinga Island, Kenya.

The anatomy of the wrist of two species of the early Miocene hominoid Proconsul is described based on new material collected on Rusinga Island, Kenya. These fossils generally confirm previous findings that the wrist of Proconsul is monkey-like in much of its morphology. However, the structure of the ulnar side of the wrist, particularly the ulnocarpal joint, is significantly different from that of extant monkeys and suggests some functional affinities with extant hominoids. Thus the wrist of Proconsul is neither monkey-like nor ape-like in its total morphology. Instead, it shows a unique combination of features which once again point to the oversimplicity of forcing fossil forms into categories based only on extant taxa.

Animals↗