共查询到20条相似文献,搜索用时 515 毫秒
1.
Paul N. Newton 《International journal of primatology》1987,8(3):199-232
The social organization of hanuman langurs (Presbytis entellus;Colobinae) was studied in Kanha Tiger Reserve, Central Indian Highlands, for 2300 hr (1980–1985), in a mosaic of moist deciduous
forest and anthropogenic meadow. The langur population density was 46.15/km
2 and the mean troop and band sizes were 21.7 and 14.0, respectively. Of 14 troops, 13 were one-male and 1 was trimale. The
population adult sex ratio was 1:2.5. The majority of female sexual solicitations was directed toward the harem male. The
birth season was December to May, with an estimated gestation of 171–224 days. A review of langur reproductive seasonality
suggests that breeding throughout the year is confined to those populations able to exploit human food sources. Mortality
during the first year of life was 40%, including infanticide. A significant positive correlation was found between the age
of an infant at death or disappearance and the mother’s subsequent interbirth interval. Five cases of social change are described,
including female transfer, one-male to multimale change, troop formation, and gradual and rapid replacement of troop males.
Takeover-associated infant killing by band males, in an undisturbed moderate-density population, supported the sexual-selection/infanticide
hypothesis but not the social-pathology hypothesis. However, it could not be directly confirmed that an invading infanticidal
male gains a reproductive advantage. The male tenure of harems was estimated to be 45 months. 相似文献
2.
Paul Newton 《Primates; journal of primatology》1990,31(1):143-145
During fieldwork in Kanha Tiger Reserve, Central India, in 1980 an adult female hanuman langur (Presbytis entellus) was observed with the forearm of a dead foetus protruding from her vagina without evidence of uterine contractions. It is
likely that a transverse lie or oblique malpresentation with consequent foetal arm prolapse occurred during labour with subsequent
impaction, uterine inertia, and foetal death. The female disappeared from the troop over the following 18 hr, presumably dying
as a consequence of the complications of the malpresentation. 相似文献
3.
A population of langurs (Presbytis entellus)at the Rajaji Wildlife Sanctuary in northern India was investigated for 1820 hr throughout a 10-month period in 1978. Data
were collected from four bisexual troops and the adult males that ranged outside of bisexual troops. Most (60%) of the observation
hours occurred with a main study troop from which social and ecological data were collected. The langur population at Rajaji
shows pronounced birth and mating seasons. The population density is high (ca. 80/km
2), with about 75% of the adult males living outside of bisexual troops, which typically are large and multimale. Males outside
of bisexual troops occur in small all-male bands or as isolates. Relations between bisexual troops and all-male bands are
characterized by relatively low levels of aggression, and members of all-male bands are able to associate with bisexual troops
for prolonged periods during the mating season. As a result of these associations, nontroop males are about as successful
as troop males in achieving reproductive access to troop females. These associations between bisexual troops and all-male
bands occurred with a minimal amount of agonistic behavior and without mortality or injury to troop females or immatures. 相似文献
4.
Jolly Alison Dobson Andrew Rasamimanana H. M. Walker John O'Connor Sheila Solberg Margaret Perel Valerie 《International journal of primatology》2002,23(2):327-353
We censused Lemur catta within a 1 km2 study area at Berenty Reserve, Madagascar, during the September–October birth season for 19 years between 1963 and 2000, a total of 290 troop counts (266 with age and sex). The non-infant population was 155 in 1972–5, fell to 105 in 1985, and rose to a maximum of 282 in 1997, while troops increased from 12 in 1972–1985 up to 25 in 1998–2000. Local density varies between habitat types from 1 per ha to ca. 6 per ha. Troops fission at ca. 15–25 individuals, or 6–10 females. Adult sex ratio has no apparent correlation with fissions, birth rate or survival. Birth rate falls steeply with number of adult females, from 80–100% in 2-female troops to about 50% in 8–10 female troops. The penalty for large troop size is greater in the dense, rich areas, but nonetheless troops there are also larger. One-year-survival does not vary with troop size, and is lower in the sparse, dry zone. Troop size is too large for optimal birth rate, but fissioning to much lower size might make troops too small for optimal adult survival, given the intense intertroop competition. This reflects Sibley's (1983) conjecture that troop sizes may not reach stable optima. Rainfall per lemur-year (beginning Oct 1) varied from 265 to 894 mm. Drought followed by rain can eliminate >90% of a cohort, especially in the dryest zone. Possibly this results from fruit failure in years following drought. It is unknown whether food supplementation of some Berenty troops is dangerous for the forest, or helpful for an isolated and vulnerable ring-tailed lemur population. 相似文献
5.
H. J. Young 《Oecologia》1988,76(3):461-466
Summary Genetic neighborhood size and area were estimated from pollinator movements over 3 years in a scarab beetle-pollinated clonal herb, Dieffenbachia longispatha (Araceae) at the La Selva Biological Station, Costa Rica. This species was characterized by low densities of reproductive individuals and asynchronous flowering within the population. The pollinator flight distributions were characterized by relatively long mean distances between consecutive visits to inflorescences (83 m) and movements to the nearest neighboring inflorescence in the appropriate phase of flowering. Pollinator movement distributions between consecutive visits to inflorescences were significantly leptokurtic in 2 of the 3 years. I calculated neighborhood sizes incorporating the levels of kurtosis and found minimal estimates of N
e to be 227–611 ramets and neighborhood area to be 88 000–180 000 m2. The three beetle species that made 94% of the visits (Cyclocephala gravis, C. amblyopsis, and Erioscelis columbica) varied in their flight distributions and in their contributions to the estimates of neighborhood size. Cyclocephala amblyopsis exhibited the greatest degree of kurtosis in its movement patterns, and neighborhood size based on its movement was large relative to N
e calculated from movement distributions of the other two beetle species. Long-distance movements of C. amblyopsis (>300 m) accounted for 68% of the neighborhood size. 相似文献
6.
Jane Boggess 《International journal of primatology》1980,1(3):233-274
Data on intermale social relations and troop membership changes in one Nepalese high-altitude population of free-ranging langurs (Presbytis entellus)are reported here. Data were collected from six troops by three observers and cover 32 months of observations. The predominantly
multi-male troops indicate an alternating pattern of exclusions and introductions with gradual adult male replacement. Takeovers
and infant killing were not observed. Analysis of adult social behavior records show qualitative and quantitative differences
in intrasexual relations, with primarily agonistic social contacts occurring between males. Agonistic encounters between females
and between males differ in frequency of occurrence, types of be-haviors used, cause, and consistency in direction of threats
between individuals. Individual adult male frequency of interaction with females and immatures varied significantly, with
the majority of these interactions occurring between the dominant troop male and other troop members. Data indicate that intermale
dominance is a major factor in determining male access to fertile females: This appears to be achieved by either directly
excluding males from the troop or effectively “controlling” their inter-actions with troop females. Data from these studies
are compared with data from other Presbytis entellusinvestigations. Review of these data suggests that intraspecific variability in intermale social dynamics and type of troop
male membership change are correlated with the percentage of nontroop males. It is suggested that environmental pressures
resulting in social crowding can be critical in determing the occurrence of takeovers in some populations of Presbytis entellus. 相似文献
7.
Estrada A Castellanos L Garcia Y Franco B Munoz D Ibarra A Rivera A Fuentes E Jimenez C 《Primates; journal of primatology》2002,43(1):51-58
A survey of the population of the black howler monkey (Alouatta pigra) present at the Mayan site of Palenque was conducted during 2000. A total of 911 man/hours, spread over 112 days were spent
surveying the 600 ha area of pristine forest at the site for howler troops. We detected the presence of 136 individuals of
which 131 were members of 20 troops, the rest were 3 solitary adult males and 2 adult males travelling as a pair. Ecological
density was estimated at 23 individuals/km2. Mean troop size was 7.0 individuals and it ranged from 2–12 individuals; 60% of the troops were multimale. All sighting
of howler monkeys were in evergreen rain forest and 75% were in trees ≥20 m in height. The reported densities and mean troop
size are higher than those reported for the species in Guatemala and in central Quintana Roo, Mexico. The vegetation of the
forest contains tree species reported to be used by species ofAlouatta in the Moraceae, Sapotaceae, Leguminosae, and Lauraceae plant families. Protection of a large perimeter area (ca 1700 ha)
around the archeological site by the Mexican government ensures the conservation of the forest and of the black howler monkey
population present at the site. 相似文献
8.
We describe the population structure and ranging patterns of a troop of Sichuan snub-nosed monkeys (Rhinopithecus roxellana) based on a study conducted between November 2002 and November 2003 in Zhouzhi National Nature Reserve, Shaanxi Province,
China. The troop comprised several 1-male units and an all-male unit. Opportunistic censuses revealed that there were ≥112
individuals in the troop. The adult sex ratio (male vs. female) was 1:3.7. The ratios of adults to immatures and infants to
adult females were 1:0.7 and 1:2, respectively. Via a grid system, we estimated the home range of the troop to be 18.3 km2, of which 7.4 km2 was the core area. The subjects exhibited distinct seasonal ranging patterns. Their movement across the home range was extensive
in spring and restricted in autumn. In addition, reuse of quadrats was highest in winter and lowest in spring in comparison
with other seasons. The daily path length (DPL) varied from .75 to 5 km, with a mean of 2.1 km. Seasonal analysis showed that
DPL is significantly shorter in winter than in spring or summer; however, there is no significant difference between the DPLs
of spring and summer or those of spring and autumn. The monkeys occupied elevations 1500–2600 m above sea level; the annual
mean of altitudinal range is 2137 m. Contrary to early studies that reported Rhinopithecus roxellana migrates to lower elevations in winter, we found no evidence supporting a seasonal altitudinal shift. Using the highest troop
count and home range estimate, and considering the extent of range overlap between neighboring troops, we calculated the population
density and biomass of Rhinopithecus roxellana to be 7.2 individuals/km2 and 68.3 kg/km2, respectively. The temporal and spatial distribution of food resources may be the most important determinant of ranging behavior
in Rhinopithecus roxellana, though understanding the relationship between resource distribution and seasonal range use may require further investigation. 相似文献
9.
Counts of 61 baboon troops (Papio cynocephalus ursinus) at four localities in the Drakensberg mountains confirmed earlier reports of a small mean troop size. This troop size of 22.49 animals changed neither with latitude nor elevation. Data from two of the sites suggested that population density increases from south to north, while a working assumption of 2.5 animals/ km2 allowed us to set the population size at 7,540 animals, living in 335 troops. Both the adult sex ratio of 2.07 females/male and the immature/ adult female ratio of 1.17 were unaffected by troop size. Repeated counts from nine known troops revealed that the population is at equilibrium. © 1995 Wiley-Liss, Inc. 相似文献
10.
Paul Newton 《International journal of primatology》1992,13(3):245-285
The feeding and ranging patterns of a troop of hanuman langurs (Presbytis entellus, Colobinae) were studied in Kanha Tiger Reserve, central Indian Highlands for 1850 hr (1981–1982), in a mosaic of moist deciduous
forest and anthropogenic meadow. The location, size, and species of each tree within the 74.5-ha troop annual range was known
and the phenology of all tree species was sampled. According to scan sampling, the troop spent 25.7% of the daytime feeding,
with range use concentrated on an island of dry deciduous forest. Whereas adjacent troops occupied only the periphery of the
focal troop's range, all-male bands occupied its center, especially during takeover and infanticidal attacks. The troop consumed
items from 60 of the 67 species of trees and woody climbers available; mature leaves (34.9% of feeding time), fruits (24.4%),
leaf buds (10.6%), flowers and flower buds (9.5%), young leaves (3.6%), insects (3.0%), and gum (1%). The monthly utilization
of fruit, open leaf buds, and flower buds is correlated significantly with their abundance, and the troop spent significantly
more time feeding and less time moving when consuming mature leaves. Comparison of tree dispersion and langur ranging patterns
suggests that the distribution of the most important food trees is a major influence on their range use. 相似文献
11.
J. A. Horrocks 《International journal of primatology》1986,7(1):31-47
Life history data are presented for a population of vervets, Cercopithecusaethiops sabaeus, in Barbados, West Indies. The data were obtained from two habituated troops and from vervets captured during
a large-scale trapping program. Individuals of known age from one troop were weighed periodically, and separate growth curves
generated for males and females. The mean weight of captured adult females was 3.3 kg; that of adult males, 5.3 kg. The average
age at sexual maturity is estimated at 34 months for females and 60 months for males. Vervets give birth throughout the year,
but most infants are born between April and July. The average interbirth interval following a surviving infant is 11.8 months.
The mortality of juveniles is heaviest between birth and 2 years of age and decreases thereafter. Males emigrate from their
natal troops at sexual maturity and one incident of a juvenile female emigrating is reported. 相似文献
12.
Paul N. Newton 《International journal of primatology》1988,9(1):59-77
Data from 24 wild populations of hanuman langurs (Presbytis entellus)in south Asia are used to test hypotheses seeking to explain variation in troop structure and the incidence of infanticide.
The occurrence of infanticide is associated with a one-male troop structure and not with a high density. The density, predation,
and economic-advantage hypotheses, as explanations for the occurrence of one-male and multimale troops, are not supported
by the review. However, the monopolization hypothesis is not contradicted; the number of adult males per troop is significantly
correlated with troop size and with the number of adult females per troop. Therefore it is suggested that a one-male troop
structure will arise if a male is able to monopolize a group of females, a multimale troop if he cannot. One-male troops may
predispose to infanticide because of high variance in male mating success and high intermale competition between groups rather
than within troops. If female dispersion determines troop structure, it is speculated that females could manipulate males
to form a multimale society if the advantages in terms of infant survival and intertroop conflict exceeded the costs in terms
of not producing infanticidal “sexy sons.” 相似文献
13.
Jatna Supriatna Barita Oloan Manullang Endang Soekara 《Primates; journal of primatology》1986,27(2):185-190
Maroon leaf monkeys (Presbytis rubicunda) were studied at the Orangutan Research Conservation Project study area at the Tanjung Puting Reserve in Central Indonesian
Borneo for approximately 15 months in 1974, 1975, and 1977. Over 250 observation hr involving 300 encounters with the monkeys
were logged. Troop size ranged from three to eight individuals in the nine troops surveyed with only one adult male being
present in each troop. Home range size varied from 0.33 km2 to 0.99 km2 and correlated with troop size. Forty-six different food types were observed eaten by the maroon leaf monkeys; of these foods,
52% consisted of fruits, 36% of leaves, and 12% of flowers. 相似文献
14.
15.
Govindasamy Agoramoorthy 《International journal of primatology》1994,15(2):225-238
I studied the process of adult male replacement and social change in two one- male troops (B20 and B21) of hanuman langurs (Presbytis entellus)at Jodhpur, India. Male-male competition lasted for about 6 months before the successful takeover of one troop (B20). During
that period, five adult males from three neighboring bands (AMB7, AMB9, and AMB10) and a resident male of a neighboring troop
(B21) were involved in taking over the troop. The latter male also copulated with six females during his interim residency,
which suggests that he may have opportunistically maximized his mating chances with females of a neighboring group. During
an intertroop interaction, a 14-month-old female infant of the other troop (B21) was fatally attacked by an adult female of
the first troop and the infant eventually died. The attacker may have taken advantage of the disorganization created by male-male
competition, perhaps to eliminate a future food competitor. In addition, the first troop gained an additional feeding area
from the other troop’s range; it included a sleeping site and a waterhole, indicating that territorial fights during social
instability may have led to the expansion of the winner’s resource area. 相似文献
16.
We observed three cases of troop extinction and two cases of female fusion in the wild population of Japanese macaques on Yakushima Island, Japan. Troops P and T decreased in size relatively slowly over a few years until each troop consisted of only three monkeys. Several months later, the remaining adult female of P merged with the adjacent troop S, followed by the remaining female of T. S subsequently also decreased in size and disappeared about 2 years later. In the early stage of troop decline, the mortality rate of adult females was as low as in a growing troop, but the birthrate was quite low. In the late stage of troop decline, the mortality rate increased and the birthrate remained low. An important factor leading to troop extinction may be an increase in population density and the resulting increase in intergroup competition. During the period when P and T declined and ceased to exist, the range of the adopted troop shifted to cover their previous ranges. In the fused troop, there was no severe aggression directed towards the immigrant females or harassment from residents of the adopted troop and there was affiliative social interaction between the immigrant females and resident members. These results agree with previous reports on female fusion: it occurs when the shrinking group consists of one or no adult member, and the immigrant females are not at a severe disadvantage in their adoptive group. A possible benefit for immigrant females is to avoid disadvantage of one-adult group in conflict with conspecifics. A possible cost for immigrant females is transfer to the other troop or to unfamiliar area or both. The cost to transfer to another group may not be high because the members of the adoptive troop are relatively tolerant to immigrants. The cost to transfer to unfamiliar range may be minimized by immigration to the troop whose range shifted to the immigrants' former range. 相似文献
17.
H. Muranty M.-T. Pavoine B. Jaudeau W. Radek G. Doussinault D. Barloy 《Molecular breeding : new strategies in plant improvement》2009,23(3):445-461
Powdery mildew (Blumeria graminis f. sp. tritici) is one of the major diseases of wheat (Triticum aestivum). Adult plant resistance (APR) to powdery mildew is considered more durable than resistance conferred by major race-specific
resistance genes. The objective of the present study was a better understanding of the genetic basis of APR in RE714 by means
of QTL analysis of several resistance scores along the growing season. A population of 160 recombinant inbred lines obtained
from the cross between RE714 and Hardi (susceptible) was assessed for APR under natural infection conditions during 3 years
and a genetic map with whole genome coverage was developed with microsatellite and AFLP markers in this population. Two major
QTL on chromosomes 5D and 6A were detected each year, and 6 minor QTL were detected only in 1 or 2 years. The QTL on chromosome
5D was detected during all the growing season each year and its R
2 value varied between 8.5 and 56.3%, whereas the QTL on chromosome 6A was detected at 1–4 scoring dates in the 3 years, and
its R
2 value varied between 6.1 and 20.5%. The two QTL explained between 24.4 and 52.1% of the phenotypic variance for AUDPC, depending
on the year. The models including QTL and cofactors in the composite interval mapping explained between 29 and 72% of the
variance. The molecular markers linked to the two major QTL could be used in marker-assisted selection for adult plant resistance
to powdery mildew.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
18.
Rekha Medhi Dilip Chetry P. C. Bhattacharjee B. N. Patiri 《International journal of primatology》2004,25(6):1331-1337
Golden langurs (Trachypithecus geei) are an endangered species in a limited area of Northeast India and Bhutan. They are confined to a forest belt in western Assam between the Manas River in the east, Sankosh in the west and Brahmaputra in the south along the Indo-Bhutan border. Due to habitat destruction, their populations are restricted to fragmented forest pockets, especially in India. We compared data on an isolated population of golden langurs in the rubber plantation of Nayakgaon in the Kokrajhar district of Assam, May 2002 with an earlier census in 1997. We counted a total of 52 individuals in 3 troops in 2002. The average troop size is 17.3 (r = 7–26). The ratio of adult male to adult females is 1:3.16. Of the total population 9.6% were adult males, 21.1% were adult females, 17.3% subadult males, 7.7% subadult females, 19.2% juveniles and 25% infants. In 1997 Srivastava et. al., recorded 38 individuals in 5 troops with an average troop size of only 7.6 . Apparently troop fusion has occurred. The increased population is encouraging. 相似文献
19.
Yayat Ruhiyat 《Primates; journal of primatology》1983,24(3):344-359
Field studies of the Sunda Island leaf monkey,Presbytis aygula, were made in the montane forests of West Java at an altitude of 1,400–1,800 m between September 1976 and August 1981. The
troop size ofP. aygula varied from 3 to 12 animals and the population density was about 35 animals/km2 in Patenggang and 11–12 animals/km2 in Kamojang. They were organized essentially in one male troops, though the troops in the Patenggang area usually consisted
of only an adult pair and its offspring. Home range size was about 14 ha in Patenggang and about 35–40 ha in Kamojang. Some
of those ranges overlapped with each other. The differences between these two areas were considered to be the result of recent
habitat destruction and human impact in Patenggang. Animals spent more time in resting than other activities during a day.P. aygula in Java, consumed mainly leaves, eating less fruits and other parts of plants. Troop cohesion was tight, but social interactions
between troop members were rather infrequent. The patterns of intertroop encounters and vocal sounds were described. 相似文献
20.
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