Showing papers on "Primate published in 1976"

Molecular evidence for dual origin of mangabeys among Old World monkeys.

Abstract: THE morphological similarities among the various mangabey species have been uniformly judged by primate systematists to warrant their association in a single genus (Cercocebus) of Old World monkeys. These similarities are not, however, reflected in their macromolecules. We find that the two groups of mangabeys are, by Old World monkey standards, so different at the protein level as to force the conclusion that the genus is not a natural that is, monophyletic, group.

Morphometric affinities of the human shoulder

Abstract: To analyze differences between apes and monkeys and the affinities of man, we have studied the shoulder girdle of 327 specimens of anthropoid primates. The scapula, clavicle and humerus are viewed as an integrated functional complex on the basis of 18 measurements. Several varieties of multivariate analysis show that man is clearly closer to other hominoids than to the included monkey taxa (whether terrestrial or arboreal, Old World or New World). The marked shoulder differences between apes and monkeys and similarities between apes and man correlate with the muscular anatomy, which in hominoids allows the motions involved in their locomotion and feeding behavior. As the hominid-pongid correspondence in shoulder morphology is especially detailed regarding the functionally important joint surfaces, it is consistent with a fairly recent period of common ancestry and behavior. No hypothetical evolutionary pathway or ancestral form of the human shoulder need look far beyond the model afforded by extant pongids. In contrast with previous studies on the primate shoulder, these results agree with information accumulationg from other systems--comparative anatomy, primate behavior, and molecular biology-- in suggesting very close relationship between man and extant African pongids.

Cross-modal matching and the primate frontal cortex.

Abstract: Rhesus monkeys with selective lesions of the prefrontal system were tested on a tactile-visual cross-modal matching task. Monkeys with lesions in the banks and depths of the arcuate sulcus were impaired, while normal controls and monkeys with lesions in the banks and depths of the sulcus principalis and in the anterodorsal part of the head of the caudate nucleus were not.

Search for antigens and antibodies crossreactive with type C viruses of the woolly monkeys and gibbon ape in animal models and in humans.

Abstract: Several reports have indicated the presence of type-C viral antigens in human tumors and of viruses closely related to those of the woolly monkey and gibbon ape in cultured human cells. In the present studies, attempts to detect woolly monkeys viral antigens in human tissues, or antibodies directed against structural polypeptides of woolly monkey viruses in human sera, were unsuccessful, In contrast, it was possible to demonstrate viral antigens in tissues and antibodies reactive to viral components in several animal and even primate model systems. Further evidence against the presence of woolly monkey viruses in humans is our failure to identify spontaneous or chemically induced viruses of this group in more than 200 individual cultures of human origin examined. These findings argue against the likelihood that viruses closely related to the woolly monkeys virus are associated with human tumors or are common infectious agents of man.

Site attachment, avoidance, and intergroup spacing

Abstract: Information currently available on interactions between free-ranging primate groups comes primarily from open-country, terrestrial omnivores (baboons, vervet monkeys) or from arboreal folivores (colobus, langurs, howler monkeys). As yet, little information is available for forest-living omnivores and frugivores, despite the fact that these are the niches most widely and successfully exploited by nonhuman primates. Moreover, although it has been generally appreciated that the day-to-day movements of animals and groups can keep them apart, study of subtle processes such as intergroup avoidance has often been neglected in favor of the more spectacular aspects of intergroup aggression. This paper presents data relevant to group movements and intergroup spacing from a field study of one arboreal omnivore: the gray-cheeked mangabey Cercocebus albiqena. Long-term systematic observations, supplemented by field experiments (Waser 1975a) were used to determine the patterns of interaction and spacing exhibited by this species. In order to investigate potential advantages of the observed avoidance-based spacing pattern, data on resource use and distribution were simultaneously recorded.

Uric acid catabolism in the woolly monkey

Abstract: The degradation and excretion of 2- 14 C-uric acid were examined in three adult woolly monkeys ( Lagothrix lagothrichia ) to determine the basis for the relatively high serum and urinary uric acid concentrations previously reported in this species. Like man and the great apes which lack uricase, but in distinction to most other mammals, these animals converted very little urate to allantoin. Uric acid turnover, as has been reported for other New World monkeys, was several times that of normal man. Renal urate excretion as well as disposition by extrarenal mechanisms may protect Lagothrix from hyperuricemia. The capacity to convert urate to allantoin appears to have been lost late in the evolution of New World monkeys. The woolly monkey deserves further study as a primate model for investigations of enzyme replacement strategies.

Cellular mechanisms in the parietal cortex in alert monkey

Abstract: Publisher Summary This chapter presents a study examining cellular mechanisms in the parietal cortex in an alert monkey. A total of 856 cells were studied in the six cerebral hemispheres of three female stump-tailed monkeys (Macaca speciosa) weighing 4–5 kg. They were trained to sit, in a Faraday cage, in a primate chair designed for microelectrode studies. A cutaneous stimulator was positioned on their palms, and they were taught to detect the end of a vibratory stimulus by pressing a lever to obtain a juice reward. In other experiments, cutaneous stimuli were applied manually, or the monkeys were allowed to move their arms and reach for objects such as raisins that were offered for them to eat. Recordings were started when the monkeys had become used to the situation and were cooperative. The number of cells activated with simple skin indentation decreases posteriorly within SI, and a corresponding increase in the number of more complex cells occurs at the same time. A similar increase toward posterior is also observed in the convergence of submodalities.

|[alpha]| and |[beta]| Chains of the major haemoglobin and a note on the minor component of Tarsius

Abstract: THE position of Tarsias (the tarsier) in the evolution of the primates has long been controversial. Gadow1 placed it in a separate suborder, but Pocock2 allied it with the monkeys, apes and man in the Haplorhini, assigning the lemurs, lorisoids and tree shrews to the Strepsirhini. This was accepted by Hill3 but Simpson4 divided the primates into two suborders, Anthropoidea and Prosimii, placing Tarsius in the latter together with lemurs, lorisoids and tree shrews, though as a separate infraorder. The problem arises because of resemblances between Tarsius and the anthropoids. These include the absence of a rhinarium, a retinal structure similar to the anthropoid fovea and a haemo-chorial placenta, compared with the epitheliochorial form of prosimians, Tarsius is often regarded as a ‘living fossil’, implying that little evolution has taken place since its divergence from the other primates. The problem may be solved with the aid of data on the primary structure of mammalian proteins5: there is sufficient evidence about haemoglobin, for example, to construct a hypothetical ancestral primate sequence5–7. Using two samples of blood from T. bancanus collected during the past 3 yr, we have determined the α and β Hb chain sequences and found that, at the molecular level, Tarsius is not a ‘living fossil’ and that the most parsimonius globin trees cluster Tarsius with the anthropoids and not the prosimians, lending support to the Haplorhini-Strepsirhini classification2,3.