Showing papers on "Primate published in 1986"

Primate η-globin DNA sequences and man's place among the great apes

Abstract: Molecular studies indicate that chimpanzee and gorilla are the closest relatives of man (refs 1–7 and refs therein). The small molecular distances found point to late ancestral separations2,4,7, with the most recent being between chimpanzee and man, as judged by DNA hybridization3,8. Kluge9 and Schwartz10 contest these conclusions: morphological characters group a chimpanzee–gorilla clade with the Asian ape orang-utan in Kluge's cladistic study and with an orang-utan–human clade in Schwartz's study. Clearly, extensive sequencing of nuclear DNA is needed to resolve by cladistic analysis the branching order within Hominoidea11. Towards this goal, we are sequencing orthologues of the primate ψη-globin locus12,13. Here, we compare the newly completed sequences of orang-utan and rhesus monkey with human, chimpanzee, gorilla, owl monkey, lemur and goat orthologues. Our findings substantially increase the evidence indicative of a human–chimpanzee–gorilla clade with ancestral separations around 8 to 6 Myr ago. We also verify that neutral hominoid DNA evolved at markedly retarded rates.

Urogenital Challenge of Primate Species with Mycoplasma genitalium and Characteristics of Infection Induced in Chimpanzees

Abstract: Eighteen male and eight female primates, representing five subhuman species, were inoculated urogenitally with Mycoplasma genitalium, a microorganism recovered from men with nongonococcal urethritis. Male rhesus (Macaca mulatta) and cynomolgus (Macaca fascicularis) monkeys apparently were resistant. Female squirrel monkeys (Saimiri sciureus) and female tamarins (Saguinus mystax) exhibited low-level, genital-tract infections. Male chimpanzees (Pan troglodytes) developed an obvious genital-tract infection, with some shedding organisms for 21 weeks. M. genitalium was recovered from the blood of two of the male chimpanzees, usually when large numbers of organisms were in the urethra. Female chimpanzees generally shed organisms for 12-15 weeks. Most chimpanzees colonized with the organism exhibited increased numbers of polymorphonuclear leukocytes in the genital tract and developed a significant antibody response. The results offer substantial evidence for the pathogenicity of M. genitalium for the urogenital tract of higher primates and suggest the microorganism may have a role in human genital-tract infections.

Studies on the evolution of multiple somatosensory representations in primates: the organization of anterior parietal cortex in the New World Callitrichid, Saguinus.

Abstract: Because members of the New World family, Callitrichidae, are generally regarded as the most primitive of monkeys, we studied the organization of somatosensory cortex in the tamarin (Saguinus) in hopes of better understanding differences in the organization of anterior parietal cortex in primates and how these differences relate to phylogeny. In most prosimian primates only one complete representation of cutaneous receptors has been found in the region of primary cortex, S-I, while in all Old and New World monkeys studied to date, two cutaneous representations exist in distinct architectonic fields, areas 3b and 1. In detailed microelectrode mapping studies in anesthetized tamarins, only one complete representation responsive to low-threshold cutaneous stimulation was evident in the S-I region. This topographic representation was in a parietal koniocortical field that architectonically resembles area 3b of other monkeys, and the general somatotopic organization of the field was similar to that of area 3b of other monkeys. Cortex rostral to the single representation was generally unresponsive to somatosensory stimuli, or required more intense stimulation for neural activation. Cortex caudal to the representation, in the region of area 1 of other monkeys, was generally either unresponsive or responded to only high-threshold stimulation, although some recording sites were activated by low-threshold tactile stimulation. The present evidence, together with that from previous studies, suggests that the single, complete body surface representation in Saguinus is homologous to the S-I representation found in some prosimians (Galago, Perodicticus) and the area 3b cutaneous representation found in New World Cebidae (Aotus, Saimiri, and Cebus) and Old World Macaca. Cortex rostral to S-I in Saguinus has the appearance of areas 3a and 4 of other primates. The cortex caudal to S-I in Saguinus, while resembling area 1 in some ways, does not have all of the features of area 1 of other monkeys. In particular, the field was not easily activated by low-threshold cutaneous stimuli, as area 1 is in other monkeys, and therefore a second cutaneous representation of all body parts was not demonstrated. Thus, cortex in the expected location of area 1 of Saguinus was not as responsive as area 1 of other monkeys, and it somewhat resembled the high-threshold fringe zones found caudal to S-I in anesthetized prosimians and some nonprimates. The results raise the possibility that the area 1 cutaneous representation that is characteristic of other New World monkeys and Old World monkeys evolved from a less responsive precursor along the caudal border of S-I in early monkeys.

Ocular dominance columns and retinal projections in new world spider monkeys (Ateles ater)

Abstract: Retinal projections and the degree of ocular segregation in the striate cortex were examined by transneuronal autoradiography following unilateral intraocular injections of 3H-proline in a New World primate, the spider monkey (Ateles ater). The results show that, within the lateral geniculate nucleus (LGN), retinal fibers terminate in six principal layers and within the interlaminar spaces adjacent to the magnocellular layers, as well as the S layers ventral to the magnocellular layers. Projections to the superior colliculus, both ipsilateral and contralateral to the injected eye, were patchy and restricted to the superficial gray layer. Our main result shows that, in the striate cortex, LGN projections terminate in well-defined ocular dominance columns in layer IV. Labelled columns were most clearly delimited in layer IVb, where they averaged 373 + 42μm in width in both the ipsilateral and contralateral hemipheres, slightly smaller than those reported originally from electrophysiological studies of striate cortex in spider monkeys (Hubel and Wiesel, '68). Unlabelled intercolumns were significantly narrower than labelled columns, which suggests that there may be overlap between input from the two eyes between columns. Quantitative measures showed above-background label also in cortical layers IIIb, V, and VI. Our results support the idea that among primates, ocular dominance columns are not limited to Old World species. At the same time, it is apparent that spider monkeys are exceptional among New World primates in having sharply delimited columns. The functional significance of the variation in the degree of ocular segregation in the cortex and its relation to primate evolution are discussed.

Epitope expression on primate lymphocyte surface antigens

Abstract: The cross-reactivity of peripheral blood mononuclear cells from 28 nonhuman primates was investigated with ten kinds of Leu series of monoclonal antibodies specific to human T-, natural killer/killer-, and B-cells. The chimpanzees possessed all ten epitopes examined but the orangutan lacked Leu4 and Leu7 epitopes and the gibbons lacked Leu4, Leu7, and Leu12 epitopes. In addition to the above epitopes, the Old World monkeys lacked Leu1 and Leu10 epitopes. The Leu3a/Leu2a cell ratios varied from 0 to 1.56 among the 12 macaque species and this enabled classification of these species into three groups. In the New World monkeys, Leu2a epitope was absent, whereas Leu11a epitope was detected in several species and Leu3a epitope was found only in the owl monkeys. The prosimians expressed only HLA-DR epitope.

Sexual dimorphism and mating systems: jumping to conclusions

Abstract: Previous studies have suggested that there is a strong relationship between a high degree of aggressive competition among males for access to fertile females and large body and canine size in males. It has further been suggested that such a relationship among living primates can be used to infer the social organization of extinct primate species from the degree of sexual dimorphism exhibited. Our field studies of patas (Erythrocebus patas) and blue monkeys (Cercopithecus mitis), two species which had previously been characterized as having one-male ‘harem’ group structures, indicate considerable variability in mating systems. We suggest, on the basis of our observations of these species, that factors other than male-male competition (e.g., predation) may also have influenced the degree of dimorphism in primates.

The suitability of East African primates as animal models of visceral leishmaniasis.

Abstract: The susceptibility of four East African primate species to experimental infection with Leishmania donovani was investigated. Vervet monkeys (Cercopithecus aethiops), Sykes monkeys (C. mitis) and baboons (Papio cynocephalus) all supported low grade infections for periods ranging between four and eight months and subsequently showed evidence of self-cure. Greater bushbabies (Galago crassicaudatus) remained completely refractory throughout the course of the experiment. The significance of hepatic histiocytic nodules in the infected primates, similar to those observed in asymptomatic human visceral leishmaniasis, and the susceptibility of Old World primates to experimental infection are discussed.

New World Primate Field Studies: What's in it for Anthropology?

Abstract: The living New World or neotropical primates, infraorder Platyrrhini or Superfamily Ceboidea, range from about 24?N. in Tamaulipas, Mexico (spider and howler monkeys) to about 30?S. in Rio Grande do Sul, Brazil (howlers) (167). Fossil platyrrhines have been found near the southern tip of South America in Santa Cruz, Argentina (197), but they are not known to have ranged farther north than they do today. They moved into Central America only after establishment of the Panamanian land bridge in the Late Miocene to Early Pliocene, 5-6 million years ago (235). The platyrrhines are found primarily in forested habitats, including both dry forest and rain forest, up to 3200 m elevation (night monkeys and howler monkeys) (94). Although they do not occur on open savanna as do Old World baboons and patas monkeys, howlers and marmosets and perhaps others do occur in open scrub and sparsely wooded or low canopied dry woodlandllanos (Colombia and Venezuela), cerrado (Brazil), pampas (Argentina), or chaco (Bolivia and Paraguay). All platyrrhines are diurnal except the night monkey Aotus. They range in size from the pygmy marmoset (100-120 g adult body size) to the woolly spider monkey or muriqui which weighs up to 15 kg. There are disagreements at many levels about the taxonomy of the Platyrrhini. This is not the place to discuss these problems, but recognizing the controversies, I have adopted a distillation of two modern classifications, by Rosenberger (201) and by Ford (72), as presented in Table 1. For consistency all discussions in this chapter refer to this classification. A recent alternative

Behavioural Observations on a Pair of Captive White-Faced Saki Monkeys (Pithecia pithecia)

Abstract: The white-faced saki monkey of northern Brazil is a medium-sized arboreal primate living in small family groups. There is little known of its behaviour in the field or in captivity. This study was car

The Primates of India: Status, Trends, and Conservation

Abstract: India has long been known as one of the rich primate areas of the world, both in species diversity and population abundance. Fourteen species of nonhuman primates occur in India—six species of macaques, five of langurs, two of looses, and one species of gibbon (Table 12.1). If the nations immediately east of India, Burma and Sri Lanka, are considered, two more species of macaques are included, one more species of langur, and an additional gibbon species.

Steroid-binding proteins in primate plasma.

Abstract: We used immunological techniques to compare the serum corticosteroid-binding globulins (CBG) and testosterone-estradiol-binding globulins (TeBG) of Old World primates (man, chimpanzee, cynomologus, and rhesus), New World monkeys (squirrel and owl), and prosimians (galago and lemur). Four different antihuman TeBG antisera could not differentiate human and chimpanzee TeBG and recognized the galago and lemur TeBG as similar as well as the rhesus and cynomologus TeBG, as similar. Western blots of serum subjected to sodium dodecyl sulfate gel electrophoresis, with detection by an anti-TeBG antiserum, showed similar patterns of distribution of the two molecular species of TeBG for all of the New World primates and the owl monkey. The abundance of the two TeBG species was reversed in squirrel monkey serum, while lemur and galago displayed only a single band. Four different antihuman CBG antisera grouped together the CBGs of human and chimpanzee, rhesus and cynomologus, and lemur and galago. The squirrel monkey h...

High Plasma Steroid Levels in the Squirrel Monkey: Deficient Receptors or Metabolism?

Abstract: Many New World primates such as the squirrel monkey have extraordinarily high plasma steroid hormone levels as compared to humans and Old World primates. To clarify the mechanism(s) under­lying this apparent steroid resistance, glucocorticoid and androgen binding to putative receptors in genital skin fibroblasts from several species was investigated. Differences in either affinity and/or number of binding sites were found but these were small compared to the very large differences in total or free plasma steroid concentrations between Old and New World primate species. In contrast, when the ability of fibroblasts to metabolize testo­sterone was compared, squirrel monkey cells were devoid of 5α-reductase activity which was readily demonstrated in human cells. Together with other data indicating that squirrel monkeys excrete little if any 5α- or 5β-reduced urinary steroid metabolites, these results suggest that inefficient metabolism rather than receptor binding abnormalities may account for the elevated plasma hormone levels in the squirrel monkey.

Relationship of mitogen reactivity to type D retrovirus infection in Celebes black macaques (Macaca nigra).

Abstract: The Celebes black macaque (Macaca nigra) colony at the Oregon Regional Primate Research Center has a high incidence of an immunodeficiency syndrome characterized by recurrent diarrhea and the development of retroperitoneal fibromatosis (RF). We have examined the relationship of type D viral infection to the immunodeficiency syndrome by surveying the colony for viral infection and for mitogen reactivity. Type D virus-positive monkeys (28% of the colony) have a higher prevalence of diarrhea, splenomegaly, lymphadenopathy and weight loss than do virus-negative monkeys, and RF has been found to occur only in virus-positive animals. Comparison of the concanavalin A (con-A) and phytohemagglutinin reactivities of the virus-positive and -negative populations has revealed no significant difference. However, within the virus-positive population, those with RF have reduced con-A reactivity and there are both high and low mitogen responders in the groups lacking RF. Thirty-two percent of the virus-positive monkeys are free of clinical symptoms, 40% have clinical symptoms but no RF, and 27% have clinical symptoms and RF. Five of the six monkeys with RF are older than the RF-free monkeys but monkeys are susceptible to type D retrovirus infection regardless of age or sex. The progressive nature of this immunodeficiency syndrome, its broad age range, and the probability that the etiological agent is also a type D retrovirus and the similarity of RF to Kaposi's sarcoma make this a potentially useful model for human AIDS.

Electric conductivity of the skin in humans and monkeys

Abstract: The topographic and functional correlation of acupuncture skin zones on the limbs of humans (99 healthy subjects) and monkeys (64 adult hamadryas baboons and rhesus-monkeys) was compared by measuring the electric conductivity of the skin (ECS). The profile of the ECS was found to be an informative and sensitive integrated indicator of the functional state of the body and of the autonomic nervous system. The parameter ECS showed seasonal variations and relief differences with respect to the two phases of the menstrual cycle in women. The parameter ECS displayed distinct differences between men and women as well as species differences between men, hamadryas baboons and rhesus-monkeys. The high differential informativeness of the ECS is indicated by the functional differences of the primate body under various constraint conditions. The anatomical and topographic correlation of acupuncture skin zones and similarity of ECS characteristics in man and monkeys suggest that the formation of functional characteristics of the ECS in various types of primates has a common philogenetic basis. It is concluded that monkeys can be used as an adequate experimental model for further evaluation of the ECS as a method to measure and diagnose functional and pathological changes in the body.