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.

Secondary sexual coloration and CSF 5-HIAA are correlated in vervet monkeys (Cercopithecus aethiops sabaeus).

Abstract: Background Identifying indirect markers of the physiology or neuroendocrinology of a primate can provide a powerful tool to scientists. Anecdotal descriptions and recent experimental evidence suggests that the colorful sexual skin in adult male vervet monkeys (Cercopithecus aethiops sabaeus) might be sensitive to social changes, including dominance relationships, which could be related to serotonergic activity. The present study examined whether individual differences in scrotal coloration were related to cisternal cerebrospinal fluid concentrations of 5-hydroxyindoleacetic acid (CSF 5-HIAA) in a captive population of vervet monkeys. Results Darkly colored males had relatively higher CSF 5-HIAA concentrations than paler males, and scrotal color hue was also related CSF 5-HIAA concentrations. Conclusions These preliminary data are compatible with the hypothesis that scrotal coloration serves as an indirect marker of serotonergic activity. These findings suggest that color assessments might be useful to consider for study design, as well as for animal welfare and captive management.

Observations on the female internal reproductive organs of the brown howler monkey (Alouatta guariba clamitans)

Abstract: Alouatta guariba clamitans (brown howler monkey) is an endemic primate from the southeastern Brazil tropical forests, classified as near threatened by the IUCN Red List 2007. The genus Alouatta is one of the most difficult New World monkeys to breed and rear in captivity. In this study we examined the macroscopic and histological aspects of the female genital tract of wild brown howler monkeys to provide baseline information for future reproduction research. The anatomical relationship between the vagina, uterus, broad ligament, oviducts and ovaries are those of a typical primate reproductive tract. The fundic portion of the uterus is globoid, the cervix is well developed, which confers to the uterus an elongated shape, and the vagina is a long flattened channel. Histological analysis conducted in females in the follicular phase revealed large quantities of interstitial luteinized tissue in the ovaries, a stratified nonkeratinized vaginal epithelium, lack of glands in the vaginal mucosa and simple tubular endometrial glands. The observed anatomical features should be considered in the adaptation and application of assisted reproductive techniques aimed at improving captive reproduction for species conservation.

Chimpanzee Learning and Transmission of Tool Use to Fish for Honey

Abstract: Since the early 1950s, Japanese primatologists have conducted research to examine culture in nonhuman animals (Hirata et al. 2001). Imanishi (1952) proposed that an important aspect of culture is learning from group members. In other words, if a species forms a group and this species has the ability to learn something from other group members, then this species may have created a culture. Another important aspect of culture is the transmission of behavior from one generation to the next, implying that a species with culture must live in a perpetual group. Some insects live in groups, but each group disappears after a certain period, meaning that behaviors cannot be transmitted to the next generation in any media other than genes. The same is true for any random members of the same organism that form a group for a random period.An intensive study begun in 1948 by Japanese primatologists revealed that Japanese monkeys live in perpetual groups. The scientists adopted a method unique at the time, which named individual monkeys and revealed, for example, dominance relationships and social structure. In Japanese monkey society, females remain in a natal group and males leave to join other groups; that is, each group is maintained by maternal lineage.After examining the results of this early study, Imanishi (1952) suggested that Japanese monkeys may have their own culture. Imanishi’s suggestion spurred research conducted by colleagues and students, who studied cultural phenomena in nonhuman primates, as exemplified by the study of monkeys living in Koshima Islet that wash sweet potatoes (Kawamura 1954; Kawai 1965; Hirata et al. 2001). Half a century has passed since then, and researchers have accumulated knowledge about the behaviors of several primate species. They agree that among all the primate species, chimpanzees have an immense behavioral repertoire and that each community of chimpanzees has a different behavioral repertoire which cannot be explained by ecological differences; that is, chimpanzees have their own cultures (McGrew 1992; Whiten et al. 1999; Matsuzawa 2003).

The evolution and biological correlates of hand preferences in anthropoid primates

Abstract: The evolution of human right-handedness has been intensively debated for decades. Manual lateralization patterns in non-human primates have the potential to elucidate evolutionary determinants of human handedness, but restricted species samples and inconsistent methodologies have so far limited comparative phylogenetic studies. By combining original data with published literature reports, we assembled data on hand preferences for standardized object manipulation in 1786 individuals from 38 species of anthropoid primates, including monkeys, apes, and humans. Based on that, we employ quantitative phylogenetic methods to test prevalent hypotheses on the roles of ecology, brain size, and tool use in primate handedness evolution. We confirm that human right-handedness represents an unparalleled extreme among anthropoids and found taxa displaying population-level handedness to be rare. Species-level direction of manual lateralization was largely uniform among non-human primates and did not strongly correlate with any of the selected biological predictors, nor with phylogeny. In contrast, we recovered highly variable patterns of hand preference strength, which show signatures of both ecology and phylogeny. In particular, terrestrial primates tend to display weaker hand preferences than arboreal species. These results challenge popular ideas on primate handedness evolution, including the postural origins hypothesis. Furthermore, they point to a potential adaptive benefit of disparate lateralization strength in primates, a measure of hand preference that has often been overlooked in the past. Finally, our data show that human lateralization patterns do not align with trends found among other anthropoids, suggesting that unique selective pressures gave rise to the unusual hand preferences of our species.