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91.
Although the sexual behavior of female rhesus macaques (Macaca mulatta) has been reported to decrease during pregnancy, systematic studies have been largely confined to reports of male behavior. Therefore, we designed a study to examine changes in female sexual behavior during pregnancy. Six cycling multiparous female rhesus macaques were paired during the periovulatory period of the menstrual cycle and during the first and second halves of pregnancy with six sexually experienced males of the same species. Each female was paired with the same male in all tests. The means of the behavioral measures scored on days 11–13 of the menstrual cycle, 35–56 of pregnancy, and 147–168 of pregnancy were compared. Females showed a significant decrease in the present contact ratio and the rate of threat-aways during pregnancy. Males showed lower rates of threatening-away, contacting, mounting, intromitting, and ejaculating when females were pregnant. The extent to which the decrease in male sexual behavior can be accounted for by an increase in female rejection is uncertain, but it is probably as significant as any loss of attractiveness that might accompany pregnancy. 相似文献
92.
During a long-term study of social behavior of semifree-ranging Barbary macaques, data on group transfer and sexual behavior were collected. A large population containing five groups living in a 14.5 ha outdoor enclosure was studied. Demographic data on the whole population are available for a period of six years. Data on sexual behavior of members of one large group were collected, by both focal animal and ad libitum techniques, for a period of two years. Matrilineal kinship relations of all except the oldest members of this intensively studied group were known. Males changed groups most frequently between the ages of three and five years i.e., the time at which sexual maturity was reached. While more than 30% of all males three years old and older changed groups during the study period, many males remained members of their natal group even after reaching adulthood. However, sexual interactions, especially matings between close matrilineal relatives, were found to be almost absent, suggesting that Barbary macaques are not highly inbred as formerly supposed. 相似文献
93.
James A. McNamara Michael L. Riolo Donald H. Enlow 《American journal of physical anthropology》1976,44(1):15-26
The growth of the maxillary complex of 36 rhesus monkeys (Macaca mulatta) was analyzed quantitatively and qualitatively during four defined stages of postnatal development (i.e., infant, juvenile, adolescent, young adult). At each stage, growth was observed during a 24 week period. Since some animals were observed during two successive stages of development, 47 periods of growth were studied. The incremental growth data were collected by superimposing serial cephalograms on cranial base implants and on maxillary implants. The largest increments of growth were observed in the infant animals and were successively less during the other periods studied. The horizontal growth component was more prominent than the vertical component in all age groups. The contribution of sutural growth to the vertical displacement of the maxilla was greater posteriorly, leading to a rotation of the maxillary complex during growth. The occlusal relationship was maintained by selective bone remodeling in conjunction with dentitional migration. 相似文献
94.
Johan D. Vochteloo Paul J. A. Timmermans Jo M. H. Vossen John A. H. Diujghuisen 《International journal of primatology》1995,16(3):277-293
Most surrogate-reared long-tailed macaques persistently avoid a big novel object, whereas most mother-reared subjects approach
it. A striking difference between these attachment figures is that the mothers moved about with their infants, whereas the
surrogates were fixed to the wall In this experiment, we aimed to find out whether mobility of the attachment figure plays
a part in the development of an infant’s responses to big novel objects. We studied the effects of mobility of the attachment
figure by restraining mothers in their range of action. We confined mothers of the experimental group in a small part of the
home cage. Their infants could leave the cage in which their mothers were restrained. Infants that were growing up with unrestrained
mothers made up the control group. At two different ages all infants encountered a big novel object. We used two different
objects. We found that the range of action of the mother did not significantly affect the responses of infants to big novel
objects. As in the previous studies, most of the mother-reared monkeys approached the objects. The age at which an infant
was first exposed to an object did not significantly affect its behavior toward it. Further, the two different objects evoked
the same reactions. 相似文献
95.
Retardation of bone development was observed in the Koshima troop of free ranging Japanese macaques. In the control group,
epiphyseal unions of appendicular long bones generally started to close at about 4 yrs of age and were completed at about
8 or 9 yrs of age. Limb bone unions of the Koshima troop, however, started to close at about 9 yrs of age and completely closed
at about 15 yrs of age. In the epiphyseal unions of trunk and girdle bones, the Koshima troop again showed a retardation of
closure compared with the control group. Until long bones reached their full length, that is, until about 15 yrs of age, their
size was small in the Koshima troop compared with the control group, though the sample size of the Koshima troop was small.
After 15 yrs of age, however, many osteometrical measurements of the Koshima troop were nearly the same as controls. A prolonged
growing duration compensated for the slow growth and allowed them to become as large as controls. This prolongation may be
an adaptation in response to small size during the developmental period.
In some parts of the body, however, Koshima macaques failed to reach the adult size of controls. Males were less likely than
females to reach full size. Causes of the retardation and small size in the Koshima troop are discussed, but they remain open
to further studies. 相似文献
96.
Margaret L. Walker 《American journal of primatology》1995,35(1):59-71
Fifteen female rhesus monkeys (Macaca mulatto), ranging in age from 8 to 34 years, were studied for one year to characterize the endocrine and menstrual changes associated with menopause in this species. Five monkeys were premenopausal; these younger monkeys, ages 8–11 years, menstruated and showed cyclic ovarian activity during the 12–month study period, as evidenced by menses and periodic elevations of serum estradiol (E2) and luteinizing hormone (LH) concentrations. Four females, ages 24–26 years, were in transition to menopause. Two of these perimenopausal females menstruated and secreted E2 and LH in a periodic fashion; the other two females showed elevated LH concentrations, consistently low E2 levels, and no evidence of menstruation. Six females, ages 27–34 years, were clearly postmenopausal; LH concentrations were high, whereas E2 concentrations were uniformly low. There was a significant inverse correlation between basal E2 concentrations and age, and a significant positive correlation between age and LH concentrations across all 15 animals. Hormonal changes indicative of ovulation, when they occurred, were generally restricted to the winter and early spring months. Histological analysis of ovaries from four postmenopausal females revealed little or no evidence of active folliculogenesis. These data indicate that menopause in female rhesus monkeys does not occur until the second half of thethird decade of life. © 1995 Wiley-Liss, Inc. 相似文献
97.
The COMT Val158Met polymorphism is one of the most widely studied genetic polymorphisms in humans implicated in aggression and the moderation of stressful life event effects. We screened a wild primate population for polymorphisms at the COMT Val158Met site and phenotyped them for aggression to test whether the human polymorphism exists and is associated with variation in aggressive behavior. Subjects were all adults from 4 study groups (37 males, 40 females) of Assamese macaques (Macaca assamensis) in their natural habitat (Phu Khieo Wildlife Sanctuary, Thailand). We collected focal animal behavioral data (27 males, 36 females, 5964 focal hours) and fecal samples for non‐invasive DNA analysis. We identified the human COMT Val158Met polymorphism (14 Met/Met, 41 Val/Met and 22 Val/Val). Preliminary results suggest that COMT genotype and dominance rank interact to influence aggression rates. Aggression rates increased with rank in Val/Val, but decreased in Met/Met and Val/Met individuals, with no significant main effect of COMT genotype on aggression. Further support for the interaction effect comes from time series analyses revealing that when changing from lower to higher rank position Val/Val individuals decreased, whereas Met/Met individuals increased their aggression rate. Contradicting the interpretation of earlier studies, we show that the widely studied Val158Met polymorphism in COMT is not unique to humans and yields similar behavioral phenotypes in a non‐human primate. This study represents an important step towards understanding individual variation in aggression in a wild primate population and may inform human behavioral geneticists about the evolutionary roots of inter‐individual variation in aggression. 相似文献
98.
99.
Hiroyuki Takahashi 《Primates; journal of primatology》1997,38(1):57-68
Huddling groups at sleeping sites, and allogrooming and proximity in the daytime during winter, were examined in a wild Japanese
macaque (Macaca fuscata) troop on Kinkazan Island in the non-snowy district of northern Japan. All sleeping groups, defined as a cluster in which
individuals huddle at sleeping sites, were formed on the ground. Their sizes tended to increase when the temperature was lower.
The number of adults with mutual physical contact in sleeping groups increased when the size of sleeping groups increased.
These results suggest that the physiological function of huddling is protection from low temperatures, and that macaques select
the ground as sleeping sites to form large sized groups. Huddling was performed most frequently among kin dyads. Non-related
dyads which appeared to be affiliative in the daytime also huddled frequently at sleeping sites. Even non-related dyads which
showed affiliative behavior less frequently in the daytime exhibited huddling, at night, however, they did so less often than
those of kin dyads and affiliated dyads. It appears that huddling at night by pairs that did not normally affiliate in the
daytime was made possible by the increased tolerance of individuals responding to colder temperatures at night in winter.
Furthermore, huddling, grooming, and proximity were exhibited at greater frequency between kin dyads, and between high-ranking
males and specific females of kin groups, although the dyads of individuals older than 15 years often were involved only in
huddling. These results suggest that two types of social bonds exist at sleeping sites in winter. One is the social bond common
to both the daytime and nighttime, the other is peculiar to nighttime. Consequently, the social function of huddling is that,
troop integration might increase at sleeping sites in winter as close social relationships among adults are extended more
widely than those in daytime. 相似文献
100.
Reproductive strategies of rhesus macaques 总被引:4,自引:0,他引:4
Fred B. Bercovitch 《Primates; journal of primatology》1997,38(3):247-263
Reproductive strategies incorporate a multitude of mechanisms that have evolved to promote the reproductive success of individuals.
Evolutionary perspectives tend to emphasize the advantages of male-male competition and female choice as mediators of differential
reproduction. Male rhesus macaques have not been observed to fight for access to sexually receptive females, although they
suffer more wounds during the mating season. An increased likelihood of attacks appears to coincide with male troop entry.
Males who spend more time in consort and mate with more females tend to sire more offspring. Genetic analysis of paternity
has pinpointed age and endurance rivalry, rather than agonistic competition, as key variables associated with variation in
progeny production. Female rhesus macaques often copulate with multiple males during their ovulatory period, and tend to conceive
on the first cycle of the mating season. Female reproductive success is more likely to be a function of offspring survivorship
than the identity of particular male partners. The role of female choice as a direct mediator of male reproductive success
is unresolved, but female mate selection seems to indirectly affect male reproductive success because female preference for
mating with novel males seems to foster male dispersal. Evaluating whether mating preferences for particular male phenotypes
affectsfemale reproductive success is a task for the future. A common denominator to the reproductive strategies of both female and male
rhesus macaques is that feeding patterns affect body condition which influences reproductive output and regulates relative
reproductive success. 相似文献