Primate

About: Primate is a research topic. Over the lifetime, 1250 publications have been published within this topic receiving 67388 citations. The topic is also known as: the primate order & primates.

Evolution of the hepcidin gene in primates.

Abstract: Hepcidin/LEAP-1 is an iron regulatory hormone originally identified as an antimicrobial peptide. As part of a systematic analysis of the evolution of host defense peptides in primates, we have sequenced the orthologous gene from 14 species of non-human primates. The sequence of the mature peptide is highly conserved amongst all the analyzed species, being identical to the human one in great apes and gibbons, with a single residue conservative variation in Old-World monkeys and with few substitutions in New-World monkeys. Our analysis indicates that hepcidin's role as a regulatory hormone, which involves interaction with a conserved receptor (ferroportin), may result in conservation over most of its sequence, with the exception of the stretch between residues 15 and 18, which in New-World monkeys (as well as in other mammals) shows a significant variation, possibly indicating that this structural region is involved in other functions.

Assessing Public Perceptions and Solutions to Human-Monkey Conflict from 50 Years in Sri Lanka.

Abstract: Sri Lanka is a biodiversity hotspot with high human density that contributes to increasing human-monkey conflict (HMC). In 50 years of primate studies there, the development of HMC has been documented, and many workshops and interventions organized to ameliorate HMC. These activities prompted the present survey. In the extensive lowland dry zone of Sri Lanka, the affected nonhuman primates are the toque macaque, gray and purple-faced langurs and slender loris. We surveyed and evaluated the attitudes of rural residents towards these four species in an effort to contribute to an ethnoprimatological approach to conservation, i.e., promote a coexistence and sharing of habitat between humans and monkeys. We selected 13 villages near Polonnaruwa, located centrally in the dry zone. The four nonhuman primate species differ in their behavioral ecologies, and this influenced how frequently they were thought of as pests. Most HMC was with the macaque and gray langur, less with the purple-faced langur and least with the loris. The underlying sentiment among stakeholders towards monkeys was generally either neutral or positive. Nonetheless, the majority (80%) of people desired a translocation of the troublesome monkeys from their properties to protected areas, which is impractical. Few (< 1%) openly wanted monkeys destroyed. While a traditional reverence for monkeys provides a solid basis for science and media-based education, it also contributes to the feeding of monkeys and consequent unnatural population growth, and enhanced HMC. Public understanding of the underlying causes of HMC was poor, hindering effective solutions. A combination of a feeding ban, possibly contraceptive intervention at localized HMC trouble spots, and extensive education may be the only benign alternatives to the destruction of wild primates by a powerful minority. Coexistence through strengthening and expansion of exclusive suitable protected habitats for all wildlife is a priority.

Video-Task Paradigm Extended to Saimiri

Abstract: Summary.-In the "video-task paradigm" a subject manipulates a joy-stick to move a cursor into an experimenter-defined target area on a computer monitor, generally receiving a food reward upon completion of the task. Despite the spatial separation of the joy-stick, monitor, and location of reward delivery, the video-task paradigm has been successfully implemented with several macaque species and with chimpanzees. Prehinary attempts to implement the paradigm with squirrel monkeys, however, were not successful. This report describes successful performance by a squirrel monkey in the paradigm. After learning to move the cursor to contact a small target randomly appearing at four screen locations, the monkey was readily able to move the cursor to contacc a moving target in novel locations on the monitor screen. Recently, Rumbaugh and his associates (e.g., Rumbaugh, Richardson, Washburn, Savage-Rumbaugh, & Hopkins, 1989) have reported the successful implementation of what they term the "video-task paradigm" with rhesus monkeys (Macaca mulatta). In this paradigm the monkey controls the movement of the cursor on a computer monitor using a joy-stick. The task is to direct the cursor to an on-screen target defined by various experimental parameters; successful completion of the task results in a food reward. Contrary to earlier suggestions of the primate learning literature (e.g., Jenkins, 1943; Meyer, Treichler, & Meyer, 1965), rhesus readily learned the relationship between the joy-stick displacement and cursor movement despite the spatial separation of the joy-stick, the images on the monitor, and the food reward. Furthetmore, the monkeys could correctly move the cursor to achieve and maintain contact with a moving target. Despite the capacity of rhesus macaques, chimpanzees (Rumbaugh, 1990), and bonnet macaques (Andrews & Rosenblum, unpublished data) to master these tasks, attempts to extend these findings to squirrel monkeys have not been successful (Rumbaugh, personal communication). Other empirical data support the view that the video-task paradigm may be beyond the cognitive and learning capabilities of the squirrel monkey. In addition to the lower learning-set and discrimination reversal abilities of squirrel monkeys, their discrimination ability is particularly subject to disruption by irrelevant visual cues (e.g., encasement of stimuli in Plexiglas); they also exhibit infe

The squirrel monkey: characterization of a new-world primate model of experimental choroidal neovascularization and comparison with the macaque.

Abstract: Purpose To evaluate and characterize the New-World squirrel monkey as a primate model for experimental choroidal neovascularization (CNV) studies and to compare it with the current Old-World macaque monkey model. Methods Fibrovascular tissues (FVT) were elicited in 12 maculae of seven squirrel monkeys by laser photocoagulation using optimized laser parameters (532 nm, 0.05 second, 75 micro m, 650 mW). Follow-up fundus and fluorescein angiography (FA) examinations were conducted on postlaser days 30 and 35, followed by euthanasia and histologic analysis of tissues. For comparative evaluations, FVT development also was induced and analyzed in eight maculae of four macaque monkeys with laser parameters previously used in this species (514 nm, 0.1 second, 50 micro m, 390 and 455 mW). Results FVT developed in both primate species, consisting of fibrous tissue that contained vessels that ranged from sparse but identifiable capillaries to well-established neovascular networks. Overall, 65% of the photocoagulation sites in the squirrel monkey and 37% of sites in macaque monkey elicited development of FVT. Localized FVT ranged from modest to extensive thickenings of the choriocapillaris layer. Unexpectedly, 76% of the FVT sites in squirrel monkey eyes and 27% of the sites in macaque eyes showed diffuse FVT that expanded beyond the original photocoagulation sites, accompanied by neovascular infiltration of the retina. Conclusions Like the macaque, the squirrel monkey can be considered a useful primate model for experimental CNV investigations, while additionally offering certain species-specific advantages. Diffuse FVT permit studies of antiangiogenic therapies in areas distant from laser photocoagulative trauma sites.