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.

The MHC class I genes of the rhesus monkey. Different evolutionary histories of MHC class I and II genes in primates.

Abstract: Homologues of the human HLA-A and -B MHC class I loci have been found in great apes and Old World primates suggesting that these two loci have existed for at least 30 million years. The C locus, however, shows some sequence similarity to the B locus and has been found only in gorillas, chimpanzees, and humans. To determine the age of the MHC class I C locus and to examine the evolution of the A and B loci we have cloned, sequenced, and in vitro translated 16 MHC class I cDNAs from two unrelated rhesus monkeys (Macaca mulatta) using both cDNA library screening and PCR amplification. Analyses of these sequences suggest that the C locus is not present in the rhesus monkey, indicating that this locus may be of recent origin in gorillas, chimpanzees, and humans. The rhesus monkey's complement of MHC class I genes includes the products of at least one expressed A locus and at least two expressed B loci, indicating that a duplication of the B locus has taken place in the lineage leading to these Old World primates. Comparison of rhesus monkey MHC class I cDNAs to their primate counterparts reveals fundamental differences between MHC class I and class II evolution in primates. Although MHC class II allelic lineages are shared between humans and Old World primates, no such trans-species sharing of allelic lineages is seen at the MHC class I loci.

Degeneration of Olfactory Receptor Gene Repertories in Primates: No Direct Link to Full Trichromatic Vision

Abstract: Odor molecules in the environment are detected by olfactory receptors (ORs), being encoded by a large multigene family in mammalian genomes It is generally thought that primates are vision oriented and dependent weakly on olfaction Previous studies suggested that Old World monkeys (OWMs) and hominoids lost many functional OR genes after the divergence from New World monkeys (NWMs) due to the acquisition of well-developed trichromatic vision To examine this hypothesis, here we analyzed OR gene repertoires of five primate species including NWMs, OWMs, and hominoids for which high-coverage genome sequences are available, together with two prosimians and tree shrews with low-coverage genomes The results showed no significant differences in the number of functional OR genes between NWMs (marmosets) and OWMs/hominoids Two independent analyses, identification of orthologous genes among the five primates and estimation of the numbers of ancestral genes by the reconciled tree method, did not support a sudden loss of OR genes at the branch of the OWMs/hominoids ancestor but suggested a gradual loss in every lineage Moreover, we found that humans retain larger numbers of ancestral OR genes that were in the common ancestor of NWMs/OWMs/ hominoids than orangutans and macaques and that the OR gene repertoire in humans is more similar to that of marmosets than those of orangutans and macaques These results suggest that the degeneration of OR genes in primates cannot simply be explained by the acquisition of trichromatic vision, and our sense of smell may not be inferior to other primate species

A cross-species comparison of status in small established groups.

Abstract: Seven status characteristics of small established human groups are listed and then compared to the characteristics of a chicken pecking order. Chickens and humans share, at most, three of the seven characteristics. Problems of comparing human and nonhuman behavior are discussed, and a method is suggested which compares behaviors along this series of primates: tree shrew, lemur, squirrel monkey, baboon and macaque, gorilla and chimpanzee, man. The successive primates in the series are increasingly physically similar to man. The seven original status characteristics either appear throughout the primate series or emerge as we move along the series toward man. The cross-species comparison serves as a basis for criticizing several sociological theories of status.

Route-based travel and shared routes in sympatric spider and woolly monkeys: cognitive and evolutionary implications.

Abstract: Many wild primates occupy large home ranges and travel long distances each day. Navigating these ranges to find sufficient food presents a substantial cognitive challenge, but we are still far from understanding either how primates represent spatial information mentally or how they use this information to navigate under natural conditions. In the course of a long-term socioecological study, we investigated and compared the travel paths of sympatric spider monkeys (Ateles belzebuth) and woolly monkeys (Lagothrix poeppigii) in Amazonian Ecuador. During several field seasons spanning an 8-year period, we followed focal individuals or groups of both species continuously for periods of multiple days and mapped their travel paths in detail. We found that both primates typically traveled through their home ranges following repeatedly used paths, or "routes". Many of these routes were common to both species and were stable across study years. Several important routes appeared to be associated with distinct topographic features (e.g., ridgetops), which may constitute easily recognized landmarks useful for spatial navigation. The majority of all location records for both species fell along or near identified routes, as did most of the trees used for fruit feeding. Our results provide strong support for the idea that both woolly and spider monkey use route-based mental maps similar to those proposed by Poucet (Psychol Rev 100:163-182, 1993). We suggest that rather than remembering the specific locations of thousands of individual feeding trees and their phenological schedules, spider and woolly monkeys could nonetheless forage efficiently by committing to memory a series of route segments that, when followed, bring them into contact with many potential feeding sources for monitoring or visitation. Furthermore, because swallowed and defecated seeds are deposited in greater frequency along routes, the repeated use of particular travel paths over generations could profoundly influence the structure and composition of tropical forests, raising the intriguing possibility that these and other primate frugivores are active participants in constructing their own ecological niches. Building upon the insights of Byrne (Q J Exp Psychol 31:147-154, 1979, Normality and pathology in cognitive functions. Academic, London, pp 239-264, 1982) and Milton (The foraging strategy of howler monkeys: a study in primate economics. Columbia University Press, New York, 1980, On the move: how and why animals travel in groups. University of Chicago Press, Chicago, pp 375-417, 2000), our results highlight the likely general importance of route-based travel in the memory and foraging strategies of nonhuman primates.