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1.
The intensity of sperm competition is often measured using the gonadosomatic index (testes/body weight). But sperm competition could be mediated more by size of the epididymis than by size of the testicles, and little information is available on the relationship between testicular and epididymal size. We found that both organs were positively correlated in size among male rhesus macaques. Body weight accounted for over 70% of the variance in testicle size and volumetric estimates of testicle size accurately reflected testicle weight. We conclude that methods for ascertaining testicle size are accurate, but the covariation in size between testicles and epididymis will hamper understanding of the physiological mechanisms involved in sperm competition in primates. © 1993 Wiley-Liss, Inc. 相似文献
2.
3.
Y Murayama T Ishida M Minezawa A Noguchi O Takenaka 《Journal of medical primatology》1988,17(1):31-40
A cell line (JAMH17+) resistant to 8-azaguanine was established from a human T-cell leukemia virus type 1 related virus (simian T-cell leukemia virus-1) positive Japanese macaque cell line. Lymphoblastic cell lines were established from the peripheral blood mononuclear cells of humans, hominoids, and several species of macaques by coculture with JAMH17+ in hypoxanthine-aminopterin-thymidine medium. HTLV-1 specific antigen was detected in some of the established cell lines. Phenotypic analysis showed that several cell lines of crab-eating macaques expressed Leu11a antigen, which is a marker of human natural killer cells. 相似文献
4.
Don J. Melnick 《International journal of primatology》1988,9(3):195-231
Among rhesus macaques (Macaca mulatta)and other cercopithecine monkeys, social groups occupying adjacent home ranges (i.e., members of the same local population)
exchange individuals and genes and thus exhibit marked genetic similarities. To assess the degree to which this pattern extends
beyond the local population, the genetic structure of M. mulattaand six other primate species was determined using Nei’s (1973) gene-diversity analysis. The genetic similarities seen among
social groups in the Dunga Gali population of M. mulatta (Melnick et al.,1984a) can be seen over the entire species range. Comparison of these results with the structures of other similarly organized
primate species indicates that (1) the average social group contains most of its local population’s genetic diversity, (2)
the average local population contains the majority of the genetic diversity found in the region to which it belongs, and (3)
the proportion of species gene diversity found in the average regional population varies substantially between species. Genetic
homogeneity within local and regional populations is probably the product of gene flow. The application of a number of analytical
models of selection and gene flow strongly suggests that gene flow, genetic drift, and zoogeography offer a more parsimonious
and plausible explanation for interspecific variation in regional differentiation than does stabilizing selection. 相似文献
5.
Viktor Reinhardt 《Zoo biology》1992,11(1):61-66
The sequence in which 14 laboratory rhesus macaques left their home enclosure during a routine catching procedure was recorded on 30 occasions during 6 weeks. The animals were trained to voluntarily exit one by one and enter a transport cage for weighing and/or treatment. Mean weekly exit orders cross-correlated significantly, and individuals retained their exit positions with remarkable consistency throughout the study period. An animal's position did not depend on its sex, age, or dominance rank. The oldest female never failed to enter the transport cage as number 1. When she was prevented from taking the lead, the group was hesitant but eventually proceeded in the usual order. Food was a strong, yet not absolute, incentive for the monkeys to cooperate. If they could not expect a reward, they took more time before proceeding, but did so in the habitual order. The predictability of the exit sequence has practical managerial value because it makes it possible for a single person to quickly catch a selected group member when necessary. 相似文献
6.
A direct radioimmunoassay for measuring urinary 20-hydroxyprogesterone cross-reactivity to monitor and assess luteal function and detect pregnancy in the lion-tailed macaque (Macaca silenus) is described. Urine samples were collected daily during ten nonconceptive and five conceptive ovarian cycles of five dult female lion-tailed macaques. Urine was analyzed for concentrations of 20α-hydroxypro-gesterone cross-reactivity, estrone conjugates, and creatinine. The strength of the luteal phase in normal nonconceptive cycles (n = 8) is characterized by a maximum sevenfold increase (day 9) in mean 20α-hydroxyprogesterone cross-reactivity over follicular phase levels; the duration, by a 13-day sustained elevation of mean 20α-hydroxyprogesterone cross-reactivity levels. Pregnancy is detectable from 20α-hydroxyprogesterone cross-reactivity values approximately 20 days after the periovulatory estrone conjugate peak (n = 4). Apparent anovulation (n = 1), extended follicular phase (n = 1), and early abortion (n = 1) also are detectable using 20α-hydroxyprogesterone cross-reactivity measurements. 相似文献
7.
Ursula Bartecki 《Primates; journal of primatology》1986,27(2):173-184
A study was carried out on the social position of 12 subadult males of a semifreeranging Barbary macaque population during
the non-mating season. The social position was measured in terms of spatial as well as interactive parameters. The subadult
males had social contacts to members of nearly all other age-sex classes but showed clear preferences for same-sexed partners.
Besides this differences were found between 5- and 6-year-old males with respect to their interaction profiles and the preference
for special classes of interaction partners. The terms “peripheral-central” is discussed with reference to the social structures
of macaque societies. The data of the present study indicate that the social position of subadult male Barbary macaques can
not be described by one of these terms exclusively. The results are compared to other studies on Barbary macaques and other
macaque species. It is concluded that in macaque societies subadult males are not obligatorily forced to live at the periphery
or to abide. It is proposed not to postulate stiff social structures but to put more emphasis on the range of variation among
macaque species. 相似文献
8.
Daniel Q. Estep Thomas P. Gordon Mark E. Wilson Margaret L. Walker 《International journal of primatology》1986,7(5):507-517
Copulatory data derived from observations of social groups of rhesus and stumptail macaques were analyzed to test the hypothesis
that pairs of animals would resume copulation significantly sooner if a second male copulated with the female shortly after
the first male’s ejaculation. Data from both groups supported the hypothesis. These results, extending previous studies in Macaca nemestrina,suggest that the shortening of copulatory intervals by social stimuli occurs in several species, both in social groups and
in experimentally created triads. These findings also are consistent with the hypothesis that socially mediated resumption
of mating is related to intrasexual competition among males. 相似文献
9.
David A. Hill 《Primates; journal of primatology》1990,31(1):33-50
The social relationships of adult male rhesus macaques (Macaca mulatta) in Group I of the Cayo Santiago colony were studied over a period of 14 months. Relationships were found in which adult
males and sexually mature females were persistently close to one another in nonsexual contexts, both within and across seasons.
Males of long tenure and high dominance rank tended to have more female partners, and more persistent relationships, than
more recent immigrants of lower rank. Correlations with length of tenure were stronger than those with dominance rank. Closely-related
females tended to have persistent relationships with the same male. In most cases the female was primarily responsible for
maintaining proximity in non-sexual contexts.
Dyads which were persistently within 5 m of each other in the birth season were more likely to form a consortship in the subsequent
mating season than those which had a brief relationship. A similar tendency was apparent in the 1 m data but it was not statistically
significant. There was no association between persistent proximity during the birth season and the occurrence of long, or
multiple consortships, nor with the maintenance of proximity or direction of grooming between consort partners. The pattern
of consortships was not closely related to the formation of persistent relationships in the subsequent birth season. Females
occasionally received protection from their male partners and, in some cases, spent more time in the feeding corral with them
than did other females.
Affiliative relationships can be very enduring and may have long-term benefits that were not apparent during the study period. 相似文献
10.
Meredith F. Small 《Primates; journal of primatology》1990,31(3):339-350
A captive group of rhesus macaques (Macaca mulatta) was observed during the breeding season to determine if consortship behavior, rather than promiscuous matings, resulted
in higher reproductive success for either partner. The 38 adult females in this group were observed “in consort” with the
5 adult or 4 subadult males on 179 occasions. Most of these consortships were short-term, lasting less than one day. Six females
engaged in consortships with one male that spanned more than three days, but the majority of these long-term associations
did not result in a pregnancy with that male. The term “consortship” has been traditionally accepted as a specific nonhuman
primate mating pattern, but the exact nature of this behavioral pattern and its evolutionary importance have been less clearly
understood. Consort behavior could be considered a precursor to a monogamous mating system if long-term exclusive sexual associations
resulted in higher reproductive success for the participants. But this study demonstrates that for rhesus macaques, who exhibit
both consort behavior and more promiscuous matings, there is no clear reproductive advantage to long-term consortships. In
light of the inconsistent use of the term consortship, the possible adaptive significance of an exclusive male-female sexual
association for the evolution of human mating patterns needs to be reevaluated. 相似文献