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1.
We assess life history from birth to death in male mandrills (Mandrillus sphinx) living in a semifree-ranging colony in Gabon, using data collected for 82 males that attained at least the age of puberty, including 33 that reached adulthood and 25 that died, yielding data for their entire lifespan. We describe patterns of mortality and injuries, dominance rank, group association, growth and stature, and secondary sexual character expression across the male lifespan. We examine relationships among these variables and investigate potential influences on male life history, including differences in the social environment (maternal rank and group demography) and early development, with the aim of identifying characteristics of successful males. Sons of higher-ranking females were more likely to survive to adulthood than sons of low-ranking females. Adolescent males varied consistently in the rate at which they developed, and this variation was related to a male's own dominance rank. Males with fewer peers and sons of higher-ranking and heavier mothers also matured faster. However, maternal variables were not significantly related to dominance rank during adolescence, the age at which males attained adult dominance rank, or whether a male became alpha male. Among adult males, behavior and morphological development were related to a male's own dominance rank, and sons of high-ranking females were larger than sons of low-ranking females. Alpha males were always the most social, and the most brightly colored males, but were not necessarily the largest males present. Finally, alpha male tenure was related to group demography, with larger numbers of rival adult males and maturing adolescent males reducing the time a male spent as alpha male. Tenure did not appear to be related to characteristics of the alpha male himself. 相似文献
2.
Seasonal variation in fecal testosterone levels in free-ranging male Japanese macaques (Macaca fuscata) was examined with reference to their dominance rank and age class. Six adult (>or=7 years old, three higher-ranking and three lower-ranking) and four adolescent (5-6 years old, two higher-ranking and two lower-ranking) males were selected as target animals. Fecal samples of these males were collected during the first 3-5 days of each month and analyzed by the method developed by Barrett et al. [Primates 43:29-39, 2002 b]. Testosterone levels varied significantly across the 12 months, and were highest in the early and middle parts of the mating season (i.e., October and November). Higher-ranking adult males displayed a peak testosterone level in October, whereas lower-ranking adults had no clear peak in the mating season. Such a difference in testosterone peaks in males could provide higher-ranking males more opportunities to fertilize females at first ovulation in the mating season than lower-ranking males. 相似文献
3.
Takeshi Furuichi 《Primates; journal of primatology》1985,26(3):219-237
Adult male association and its annual change were studied in a wild population of Japanese macaques (Macaca fuscata yakui) on Yakushima Island, Japan. Unlike many other Japanese macaque troops, adult troop males frequently maintained proximity
and exchanged grooming with one another in both the mating and non-mating seasons, and the dominance relationship rarely appeared
in such inter-male associations. The few cases of agonistic interactions occurred mostly when estrous females or food resources
were immediately concerned. Although troop males were very intolerant to newly appeared solitary males (new males) during
the mating season, close associations were formed between troop males and new males as soon as the mating season terminated.
The consort of new males and lower-ranking troop males with estrous females was frequently disturbed, but these males could
copulate no less frequently than higher-ranking males. A comparison among macaque species suggests the existence of two forms
of inter-male association: (1) the frequent association based on the symmetrical exchange of social behaviors; and (2) the
infrequent and asymmetrical association related to the dominance relationship. The form of inter-male association seems to
be influenced by whether or not males can keep close associations with females throughout the year. 相似文献
4.
Male Masturbation in Free-Ranging Japanese Macaques 总被引:1,自引:1,他引:0
We studied masturbatory behavior of males over a 14-mo period in free-ranging Japanese macaques (Macaca fuscata yakui) on Yakushima island, Japan. We distinguished 2 types: (1) masturbation only and (2) masturbation with final ejaculation. Both types occurred in all 15 adult troop males. We calculated masturbation only as an index (M/h). It occurred over the whole year; however, it was more frequent during the mating than during the non-mating periods. Masturbation with ejaculation was restricted to the mating period. Male mating success correlated positively with social status. Both rate of masturbation only and masturbatory ejaculations increased as male social status and male mating success declined. Lower-ranking males had higher rates of masturbation only, i.e., they spent more time masturbating than higher-ranking males did. Lower-ranking males also had higher proportions of ejaculates for masturbation, while higher-ranking males used most of their ejaculates for mating. 相似文献
5.
Observations of age-sex class associations of three young female and five young male bonnet macaques born in the spring, 1975,
were taken semiannually over three years beginning in the fall, 1975. Analysis reveals several patterns: (1) both males and
females show continuous decline in association with age mates; (2) solitary time of females peaks at 1.5 years after which
they begin to associate with adult females; (3) solitary time of males peaks at 2.5 years after which they associate predominantly
with sub-adult males; (4) both males and females showed higher association with juveniles of the same sex than of opposite
sex; and (5) both males and females showed annual cycles of association with some age-sex classes. These results are best
understood with reference to the natural breeding cycle of the animals and the different life histories of male and female
macaques in the wild. 相似文献
6.
Body size as an estimator of production costs in
a solitary bee 总被引:3,自引:0,他引:3
Abstract 1. Body weight is often used as an estimator of production costs in aculeate Hymenoptera; however, due to differences between sexes in metabolic rates and water content, conversion of provision weight to body weight may differ between males and females. As a result, the cost of producing female progeny may often have been overestimated.
2. Provision weight and body weight loss throughout development were measured in a solitary bee, Osmia cornuta (Latreille), to detect potential differences between sexes in food weight/body weight conversion.
3. Male O. cornuta invest a larger proportion of larval weight in cocoon spinning, and presumably have higher metabolic rates than females during the larval period; however, this is compensated by a slightly longer larval period in females.
4. Overall, body weight loss throughout the life cycle does not differ significantly between sexes. As a result, cost production ratios calculated from provision weights and from adult body weights are almost identical.
5. The validity of other weight (cocoon, faeces) and linear (head width, intertegular span, wing length, cocoon length, and cell length) measures as estimators of production costs is also discussed.
6. Valid estimators of production costs vary across species due to differences in sex weight ratio, cocoon shape, provision size in reference to cell size, and adult body size. 相似文献
2. Provision weight and body weight loss throughout development were measured in a solitary bee, Osmia cornuta (Latreille), to detect potential differences between sexes in food weight/body weight conversion.
3. Male O. cornuta invest a larger proportion of larval weight in cocoon spinning, and presumably have higher metabolic rates than females during the larval period; however, this is compensated by a slightly longer larval period in females.
4. Overall, body weight loss throughout the life cycle does not differ significantly between sexes. As a result, cost production ratios calculated from provision weights and from adult body weights are almost identical.
5. The validity of other weight (cocoon, faeces) and linear (head width, intertegular span, wing length, cocoon length, and cell length) measures as estimators of production costs is also discussed.
6. Valid estimators of production costs vary across species due to differences in sex weight ratio, cocoon shape, provision size in reference to cell size, and adult body size. 相似文献
7.
Toru Oi 《Primates; journal of primatology》1988,29(1):1-19
During the period from June to July 1983, the Hanyama-A troop of wild non-provisioned Japanese monkeys on Yakushima Island
began to show signs of troop fission. Adult females together with their infants and juveniles subdivided into two groups,
the Hanyama-K group and Hanyama-M group. After the subdivision, all of the troop males were observed vacillating between these
two female groups. During the mating season, non-troop males were also observed moving around the two female groups. After
this mating season, one of these non-troop males was found to have entered and become the alpha male in one of the groups,
while higher-ranking adult males of the original troop settled into the other group. Each fissioned group was strongly considered
to be composed of either high-ranking matrilines or low-ranking matrilines as observed previously in provisioned troops. The
dominance relation between the two fissioned groups indicated that dominance rank reversal between these two female kin groups
must have occurred during the course of subdivision of the troop. However, different from most previous cases of troop fission,
there was no indication that males ever participated in the subdivision of the original female group. This was disrupted not
as a result of males' involvement, but only as a result of antagonism among females, which initiated the troop fission. The
main factor which appeared to determine when and in which fission group males eventually settled was the competition between
the troop males' coalition and non-troop males and their ability to monopolize females. The present process of troop fission
suggests a dual strategy between males and females (Wrangham, 1979, 1980) even in the society of Japanese macaques. 相似文献
8.
Joseph H. Manson 《Primates; journal of primatology》1993,34(3):285-288
Five adult and subadult sons of middle- and low-ranking female rhesus macaques (Macaca mulatta) were observed to hold high dominance rank in their natal groups during a 12-month study at Cayo Santiago, Puerto Rico. Three
of these males also experienced high mating success during at least one mating season. These findings contrast with all previously
published accounts of rank acquisition by natal male rhesus macaques in provisioned colonies, and they present a challenge
to the hypothesis that natal transfer functions to increase male access to fertile females. 相似文献
9.
Michael E. Pereira 《Ethology : formerly Zeitschrift fur Tierpsychologie》1988,79(3):195-217
19 juvenile members of known genealogies in two wild baboon groups were studied over a 16-month period to compare the ontogeny of agonistic experience and dominance relations for males and females. Juveniles of all age-sex classes were disproportionately likely to receive aggression from and submit to adult males per unit of time spent in proximity. This pattern intensified with increasing juvenile age. With age, juvenile females more often submitted to unrelated adult females from higher-ranking families, whereas this was not true for juvenile males. All juveniles received aggression from older group members more often during feeding than was expected by chance. High rates of agonistic interaction with unrelated adult females accounted for old juvenile females (3–5.5 years-old) interacting agonistically more frequently than male age peers and young juveniles of either sex (1–2.5 years-old). Adult females were also more aggressive toward females among young juveniles, suggesting that adult females target females among juveniles for aggression and resistance to rank reversal. Within juvenile age groups, males dominated all females and all younger males, irrespective of maternal dominance status. Dominance relations among female age-peers were generally isomorphic with relations among their mothers. No juvenile targeted any older male for rank reversal. Males targeted all older females, whereas females typically targeted only older females from families lower-ranking than their own. The strong sexual dimorphism in adult body size in baboons may explain why juvenile males' dominance relations with peers and adult females are not structured along lines of family membership as is true for the less dimorphic macaques. Acquisition of higher agonistic status probably allows juveniles of both sexes to increase their success in within-group feeding competition during late stages of juvenility, which, in turn, could affect important life-history traits such as age at menarche and adult body size. 相似文献
10.
Rank relations of more than 100 juvenile and subadult natal Barbary macaque males were analyzed. Hierarchical relations among individuals of the same age were established early during the first year of life. With few exceptions concerning infants from very high-ranking genealogies, males dominated female peers regardless of maternal rank. Males started to outrank females from older cohorts during the second year of life and completed the process of rank reversal with adult females at 5-6 years of age. An age-graded dominance pattern existed among males from different birth cohorts. Only 3 rank reversals between males from different cohorts were observed. Rank reversals among males of the same birth cohort occurred more frequently. Rank position of a male among his male peers was influenced by birth order, by maternal rank, and by the presence of juvenile brothers. Most males without juvenile brothers had low positions, regardless of maternal rank. Males born late in the birth season were also low-ranking, even when juvenile brothers were present. There was no cohort where ranking among males was determined by maternal rank alone, as is the case in rhesus monkeys and Japanese macaques. Adult/subadult male carriers had no noticeable effect on rank positions of 'their' infants. It is suggested that a weaker influence of Barbary macaque mothers on rank of their sons is related to very early integration of male infants in male social/play groups. 相似文献
11.
Yuzuru Hamada Seiji Hayakawa Juri Suzuki Satoshi Ohkura 《Primates; journal of primatology》1999,40(3):439-452
Adolescent growth of Japanese macaques (Macaca fuscata) was studied. Their growth is composed both of a seasonal cycle of acceleration and deceleration and of linear increases.
There is a major growth spurt in linear dimension and body weight at the beginning of the breeding season of the third and
fourth year of life in females and males respectively, when they mature reproductively. They show additional accelerated growth
in the following year(s). These growth spurts, in total, are considered to correspond with the adolescent growth spurt in
humans. Adolescent growth of Japanese macaques is characterized by a punctuation by slower growth and a later start, which
is considered to be the product of adaptation to a strongly seasonal environment. 相似文献
12.
A comparison of the mating behavior of adolescent and adult female rhesus macaques (Macaca mulatta) 总被引:2,自引:0,他引:2
This study compares adult and adolescent female rhesus macaques with regard to (1) characteristics of their copulatory partners,
(2) their proceptive behaviors, and (3) adult male behaviors toward them during estrus. We conducted focal follows of 24 adolescent
and 65 adult free-ranging estrous female rhesus macaques on Cayo Santiago during two mating seasons. Compared to adult females,
adolescents presented sexually to males at higher rates; copulated more frequently with rankless young male, and extra-group
males; and, in one of two mating seasons, were ignored more frequently by males to whom they presented sexually. Adolescents
tended to copulate with ranked, resident males at higher frequencies on days when the operational sex ratio (adult males:estrous
adult females) was high. Males directed “muzzle-up” signals to adolescents at lower rates than to adults in one of two mating
seasons, although this effect vanished when males who might have fathered adolescent females were excluded from analysis.
Adolescents did not differ consistently from adults in strength of the correlation between proximity maintenance (dyadic Hinde's
Index) and copulation rate, or in approach rate to males. Adolescent females, relative to adult females, presented sexually
more to rankless young males, but did not present more to ranked, resident males. Both proximate (e.g. endocrine) and ultimate
(e.g. differential fecundity; female-female mate competition) explanations may account for the reported differences between
adult and adolescent female rhesus macaque sexuality. 相似文献
13.
Christin Richter Lieke Mevis Suchinda Malaivijitnond Oliver Schülke Julia Ostner 《International journal of primatology》2009,30(4):625-642
Macaque social relationships differ greatly between species. Based on captive studies that focus mainly on females, researchers
have classified stumptail macaque (Macaca arctoides) social relationships as tolerant, as indicated by a high rate of affiliation, frequent aggression, and symmetrical conflicts.
To accumulate more data on male social relationships, which are relatively understudied, and to generate comparative data,
we investigated male social relationships in a provisioned group of 68 free-ranging, naturally dispersing stumptail macaques
in southern Thailand. We collected continuous focal animal and ad libitum data on 7 adult and 2 subadult males, recording social behavior during 283 contact hours between December 2006 and March
2007. Stumptail macaques of this population were less tolerant than predicted based on previous studies on captive groups:
Rates of spatial proximity, affiliation, and aggression were low, most males directed affiliative behavior toward higher-ranking
males, and conflicts were generally of low intensity and relatively asymmetrical. Thus, male stumptail macaques of the focal
group appear to differ in their social style from a previous study of a captive group that mainly comprised of females. In
some traits, they are even more intolerant than rhesus macaques, an intensively studied intolerant macaque species. We also
compare our data on stumptail macaque males to those on other male macaques, but available data are too sparse to draw final
conclusions. 相似文献
14.
Hiroyuki Takasaki 《Primates; journal of primatology》1985,26(2):121-129
The mating behavior of receptive females in the M group chimpanzees (Pan troglodytes schweinfurthii) of the Mahale Mountains, western Tanzania, was studied by intensive sampling over a period of 5 months. Restrictive matings
were observed only between parous females mostly in the ovulatory stage and prime adult males, in particular the alpha. Young,
nulliparous and/or non-ovulatory females tended to mate with immature or low-ranking adult males. By contrast, older, parous
and/or ovulatory females tended to mate with adult and higher-ranking males. These confirmed the results of a previous extensive
study of the same group. In addition, gradual shift from opportunistic to restrictive matings after inter-unit-group transfer
was revealed for 2 ex-K-group parous females. The findings were discussed in relation to the life history of female chimpanzees.
A National Park since 1984. 相似文献
15.
Mewa Singh H. N. Kumara M. Ananda Kumar Mridula Singh Matthew Cooper 《International journal of primatology》2006,27(2):515-528
In bonnet macaques, males usually disperse between groups and females remain philopatric, but researchers have reported female
transfer. We report a rare case of male influx during the mating season in our bonnet macaque study group in the Anaimalai
Hills. The density of bonnet macaques in the study region was unusually high. The study group had a single, crippled adult
male with a long tenure and 5 adult females. During the mating season, adult females approached and mated with outgroup males,
and then several males entered the group. The adult male left the group without any resistance. The incoming males mated with
3 receptive females, forcibly mated with 2 lactating females, and attacked and killed 2 infants. During the influx, 2 outgroup
females joined the group. The data suggest that male influxes provide an opportunity for infanticide and female transfer,
which can have important fitness consequences even in species in which they rarely occur. 相似文献
16.
Female rank and reproductive success among arashiyama B Japanese macaques (Macaca fuscata) 总被引:2,自引:0,他引:2
Linda D. Wolfe 《International journal of primatology》1984,5(2):133-143
Five hypotheses that related female rank and reproductive success were tested in an intact troop of free-ranging, provisioned,
Japanese macaques. The hypotheses stated that high-ranking females (1) begin parturition earlier in life than low-ranking
females; (2) produce more offspring than low-ranking females; (3) give birth during some optimal time during the birth season
to a greater extent than low-ranking females; (4) experience less infant mortality than low-ranking females;and (5) more frequently produce male offspring, while low-ranking females more frequently produce female offspring. A statistical
analysis of the data which included three birth seasons and 55 adult females and 34 pubescent females, all of known age, rank, and matrifocal membership in the Arashiyama B troop, revealed few significant results. An association was found between
the rank of the matrifocal unit and the age of first birth. However, the relationship was the reverse of hypothesis 1, i.e.,
females of the lower-ranking matrifocal units began parturition earlier than females of higher-ranking matrifocal units. Therefore,
in this troop of Japanese monkeys— where alternative feeding strategies existed— there was little association between female
rank and reproductive success. 相似文献
17.
In captivity, male bonnet macaques (Macaca radiata) frequently express "friendship" toward one another, including affiliative behavior such as huddling, grooming, coalitionary support, and sitting in close proximity. The purpose of this study was to determine whether wild adult male bonnet macaques also express "friendship" by investigating whether or not (1) adult male bonnet macaques have affiliative social relationships with other males, (2) the strength of social relationships varies among dyads, (3) there is time-matched reciprocity in allogrooming among dyads, and if so, whether the level of reciprocity occurs within a bout of grooming, a day, or over 2 months (the limit of this study), and (4) a correlation exists between the strength of social relationships and dominance ranks among adult males. Focal samples totaling 150 hr on all seven adult males in one study group were conducted to record both agonistic and affiliative interactions. Agonistic interactions were used to construct a dominance hierarchy, whereas affiliative interactions (sitting in proximity to within 1 m with and without grooming) were used to quantify the existence and strength of social bonds within dyads. Results show that adult male bonnet macaques had differentiated affiliative relationships with other males in their group. There was little reciprocity of grooming within a bout of grooming or within a day, but greater reciprocity over the study period of 2 months. There was no correlation between dominance ranking distance and the strength of affiliative relationship within dyads; however, within dyads lower-ranking males groomed higher-ranking males more than vice versa. This study suggests that friendships in male bonnet macaques are characterized not by immediate tit-for-tat reciprocal altruism, but by reciprocity over a longer time span, and that affiliative social relationships may be less constrained by agonistic relationships than is the case in more despotic species of macaques. 相似文献
18.
Setchell JM Lee PC Wickings EJ Dixson AF 《American journal of physical anthropology》2001,115(4):349-360
We present body mass (N = 419) and crown-rump length (CRL, N = 210) measurements from 38 male and 49 female mandrills born into a semifree-ranging colony in order to describe growth from birth to adulthood, and to investigate maternal influences upon growth. Adult male mandrills are 3.4 times the body mass, and 1.3 times the CRL, of adult females. Body mass dimorphism arises from a combination of sex differences in length of the growth period (females attain adult body mass at 7 years, males at 10 years) and growth rate. Both sexes undergo a subadult growth spurt in body mass, and this is much more dramatic in males (peak velocity 551 g/months +/- 89 SEM at 84-96 months). CRL dimorphism arises from bimaturism (females attain adult CRL at 6 years, males after 10 years), and neither sex shows a particular subadult growth spurt in CRL. Sexual size dimorphism thus represents important time and metabolic costs to males, who mature physically approximately 3-4 years after females. Considerable interindividual variation occurs in the size-for-age of both sexes, which is related to maternal variables. Older mothers have heavier offspring than do younger mothers, and higher-ranking mothers have heavier offspring than do lower ranking mothers. Mass advantages conferred upon offspring during lactation by older and higher-ranking mothers tend to persist postweaning in both sexes. Thus maternal factors affect reproductive success in both sexes, influencing the age at which offspring mature and begin their reproductive career. 相似文献
19.
This report outlines a comparison of renal weight and volume and selected skeletal parameters to sex in 22 adult male and 156 adult female rhesus macaques. Means and standard deviations for kidney weight and volume, body weight, and radiographic measurements for both males and females are reported. Ninety-five percent confidence intervals and P-values for the mean differences between the sexes for these parameters were also compiled. Male monkeys were larger, but had kidneys of similar size to those of the females. Joint distributions of the radiographic measurements of the first lumbar vertebra and the skull showed that males were larger in both measurements. The distributions of these parameters were clearly separate in males and females, while joint distributions of kidney weight and volume for males and females overlapped almost completely. We found that, regardless of age, sex, weight, or skeletal size, all normal adult rhesus monkeys generally have similar-sized kidneys. 相似文献
20.
Joseph H. Manson 《Primates; journal of primatology》1994,35(4):417-433
Birth season adult heterosexual nonkin relationships of 50 free-ranging female rhesus macaques (Macaca mulatta) in two social groups at Cayo Santiago, Puerto Rico were examined using focal follow (289 hr) and ad lib data. Eighty-eight
percent of subjects had at least one relationship characterized by particularly high frequencies of spatial proximity, grooming,
or both. These were designated “friendships.” Males intervened in aggressive interactions more frequently on behalf of Friends
than non-Friends. Female aggressive support of males was extremely rare. Higher-ranking males experienced more friendships
than lower-ranking males. High-ranking females had higher-ranking Friends than low-ranking females. Older females had higher-ranking
Friends than younger females. Females groomed high-ranking Friends more than they were groomed by them, whereas they groomed
low-ranking Friends less than they were groomed by them. In one social group, high-ranking females were more likely than low-ranking
females to groom their Friends more than they were groomed by them. Males were more responsible than females for spatial proximity
maintenance in 9 of 14 Friend dyads for which sufficient data were available. Neither male nor female dominance rank affected
responsibility for proximity maintenance in Friend dyads.
Eight of 24 females had friendships with males with whom they had completed copulations during their conception peri-ovulatory
period of the preceding mating season. Two of 19 females completed peri-ovulatory copulations with Friends during the following
mating season. Friendship was not correlated with either of two demonstrated female mate choice indicators: (1) proximity
maintenance during estrus; or (2) cooperation with male “hip-grasp” courtship attempts. Males directed “muzzle-up” courtship
signals at lower rates toward Friends than toward non-Friends.
These and other investigators' results indicate that (1) protection from aggression is the primary benefit to female rhesus
macaques of birth season heterosexual relationships; (2) the most effective protectors are in greatest demand as Friends;
and (3) friendship has no effect or an inhibitory effect on mate choice in this species. Benefits to males of friendships
were not apparent from this study but may include coalitional support against lower-ranking males. 相似文献