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.

Molecular evolution of the HERV-E family in primates

Abstract: More than 50 copies of HERV-E family elements have been estimated to exist in the human genome. Here we examined the recent evolutionary history of the HERV-E family by a PCR approach using genomic DNA from hominoid primates and a human monochromosomal panel. From the HERV-E family, 25 and 68 env fragments, were identified and analyzed from hominoid primates and human chromosomes 1, 2, 3, 4, 6, 7, 8, 10, 11, 12, 13, 14, 15, 16, 17, 19, X, and Y, respectively. They showed 76.7-99.6% sequence similarity to that of HERV-E (accession no. M10976). Phylogenetic analysis of HERV-E env family distinctively divided into two groups (groups I and II) that each contained three subgroups. Divergence times of the two groups were estimated as 10.7 MYr for group I and 41.3 MYr for group II using an average evolutionary rate of 0.3% per MYr. These data are consistent with that of PCR analysis, which showed a band of the HERV-E family in the genomes of the hominoids, Old World monkeys, and New World monkeys. Therefore, the HERV-E family may have integrated into the primate genome after prosimians and New World monkeys diverged. Then they proliferated extensively in the genome of humans and great apes during primate evolution.

Function of the Subclavius Muscle in a Nonhuman Primate, the Spider Monkey (Ateles)

Abstract: Within the primate order, the morphology of the subclavius muscle is known to be unique among the prehensile-tailed South American monkeys. 3 spider monkeys, Ateles, were monitored electromyographically to determine the recruitment of this muscle during various locomotor and postural activities. Rather than indicating a static stabilizing function, which has typically been inferred from classical anatomical studies, results from this study suggest that the subclavius performs more as a dynamic element in movements of the pectoral girdle during brachiation, vertical climbing, pronograde quadrupedalism and leaping. Complementary activity patterns were also identified between the subclavius and the caudal fibers of the trapezius indicating that the subclavius is used when the animal must depress, or resist cranial displacement, of the protracted shoulder girdle, while the caudal trapezius is recruited when the girdle is retracted on the chest wall.

Growth in Howler monkeys

Abstract: Howler monkeys (Alouatta caraya) were studied in northern Argentina and subjected to complete post-mortem examination in connection with field observations of atherosclerosis. In order to estimate age of the animals, data was obtained on gross body dimensions, dental age, and organ weights in 298 animals covering the range of about 1–10 kg. The animals were divided into four size groups, and into male, non-pregnant and pregnant female categories. Statistical parameters were obtained for relative organ weights, organ allometry coefficients, gross body lengths, a body length formula based on the Ponderal Index and dental age. The parameters from howlers were compared with those for rhesus monkeys, chimpanzees, human and general primate organ allometric formulas, and differences due to sex and pregnancy reviewed. It is concluded that the growth pattern in howlers is rather similar to that reported for other primates, which makes it possible to estimate maturity satisfactorily, but that further methods must be developed for post-maturity dating.