How old is Hanuman

Hanuman langurs

Hanuman langurs (Semnopithecus) count within the vervet family members (Cercopithecidae) to the tribe of the Schlankaffen (Presbytini). In English, animals are Gray langurs indicated. In the validated system, 7 species are listed in the genus. The assignment is currently being discussed for 2 other species.

description

Appearance and dimensions

Hanuman langurs are relatively large slender monkeys (Presbytini). In terms of size, however, the individual species differ considerably. In some species, there is also considerable dimorphism between the sexes. The fur is usually grayish to yellowish white or light brown to grayish brown in color. In contrast, the faces and the visible areas of skin are colored black. The tail, which is longer than the body of all species, is also a striking feature. Some species have black colored tail tips. According to Groves (2001), this applies above all to the northern populations. The largest species of Hanuman langur are the Nepalese Hanuman langur (Semnopithecus schistaceus) and is the Kashmir Hanuman Langur (Semnopithecus ajax), the Dussumier Hanuman langur (Semnopithecus dussumieri) is the smallest species. A striking feature of the black-footed Hanuman langur (Semnopithecus hypoleucos) are the dark, almost black colored legs and arms as well as the slightly orange-brown colored belly. In all species the ventral fur is lighter in color than the dorsal fur (Groves, 2001; Davies, 1994).

The dimensions and weights of the individual types are given below. The data are not complete and will be supplemented.

Common nameScientific namebody length
in cm
Tail length
in cm
Weight
in kg
source
Cashmere Hanuman LangurSemnopithecus ajax 67,1 n / A 17.7 (m / f) Roonwal, 1981
Dussumier Hanuman LangurSemnopithecus dussumieri n / A n / A n / A n / A
Bengali Hanuman LangurSemnopithecus entellus 63,9 n / A 12.5 (m / f) Roonwal, 1981
Tarai Hanuman LangurSemnopithecus hector n / A n / A n / A n / A
Black-footed Hanuman langurSemnopithecus hypoleucos n / A n / A n / A n / A
Southern Hanuman langurSemnopithecus priam 61,1 n / A 12,8 Roonwal, 1981
Nepalese hanuman langurSemnopithecus schistaceus 68,9 n / A 17.7 (male)
15.8 (female)
Roonwal, 1979

Hanuman langurs move quadrupedal (from Quadrupedie, lat. quadrus = four and pes = Foot) on all four extremities. Rather seldom do the animals move around on the ground, hopping on two legs. High up in the trees, Hanuman langurs are characterized by active jumpers who can easily manage horizontal jumps of up to 460 centimeters. (Badam, 1998; Ripley 1967). Water is avoided, but Hanuman langurs can swim well.

Way of life

Social organization and behavior

Hanuman langurs live in social groups that differ in composition and size depending on their species and habitat. All groups have a polygamous composition. There are groups with one male, but also with several males. The group size can be only a few individuals, but also 50 or even 90 animals. Groups of well over 100 animals are also known. According to Chhangani (2002), three different social systems are known. These are:

  • Groups with one Males and several females and their offspring
  • Groups with several and several females and their offspring
  • and groups with only males

Groups with only males do not meet sexually mature females until the mating season. All three group compositions can occur in all 7 species or populations. Groups with only males are significantly smaller than mixed-sex groups. In addition to adult males, subadult males are also integrated in these groups. In the mixed-sex groups there is a strict hierarchy between the females and males. The composition of a group is usually long-term and stable. The hierarchies are linear and are essentially based on age and physical condition. In the groups with only males, the ranking is mostly determined by fighting or reproductive success. It is not uncommon for these groups to split up into subgroups during the day or for a longer period of time. Smaller groups tend to be more successful in their search for food or females (Rajpurohit, 1992, 1995; Vasudevet al. 2008). The social relationships within a group are based on gender. Males stay to themselves and seek close contact with the females only during the mating season. The contacts between the males can be both peaceful and combative in nature. The contacts between males and females are mostly peaceful. Females groom each other, which is largely based on rank within the hierarchy. Lower-ranking females behave submissively to high-ranking females. The higher the rank, the sooner the females will benefit from personal hygiene. Aggressive interactions can certainly occur between 2 high-ranking females. However, real conflicts are usually avoided (Rajpurohit, 1995; Sommeret al. 2002). The relationships between two groups are usually agonistic. The fights are usually carried out by the high-ranking males of both groups among themselves. Before there is any real brawl, the males of both groups meet each other visually and tactilely. Only when the first intimidation does not bear fruit does persecution and fighting occur (Rajpurohit, 2003).

Males who are about to reach sexual maturity leave the birth group. They either leave the group immediately and join a bachelor group, or they are gradually pushed to the edge of the group by the females and therefore leave the group later. Most males leave the group very quickly due to the increasing aggressiveness of the group members. The emigration usually takes place at the age of 30 months. In the bachelor group, new members initially rank low in the hierarchy. Field studies have shown that males stay in a bachelor party for up to 4 years. Females usually stay in their natal group for life (Rajpurohit, 1993, 2003; Newtonet al. 1987).

communication

According to Bhaker (2004), 19 different sounds have been detected in the field so far. These are coughing, barking, grunting and similar sounds. Hanuman langurs make themselves particularly vocal in the early morning hours. At this time, the animals swarm from their roosts in search of food. Adult and sub-adult males make particularly harsh, barking sounds when natural enemies approach. Bell cough can mainly be heard when hiking and looking for food. Grunting noises are also the rule on hikes, but also during agonistic behavior. Rumbling exclamations can also be heard in agonistic situations. Males make loud mustache noises during social interactions. These noises express a sense of well-being. Young animals draw attention to themselves by screaming alarm calls, but also by plaintive, squeaking and trilling exclamations (Bhaker, et al. 2004).

Activity pattern

The diurnal Hanuman langurs stay in so-called sleeping trees during the night and when they are resting. Usually the sleeping places are at heights of more than 10 meters above the forest floor. Here, Hanuman langurs are safe from most natural predators. In human settlements, Hanuman langurs sleep on telephone poles, towers, electricity poles or similarly protected places (compare Ramakrishnan & Coss, 2001). In natural habitats Around 26% of the active time is used for eating, 42% for resting phases, and 13% for hiking. The rest of the time, there are social activities such as grooming. Activity patterns may vary depending on the time of year.

Territory and territory behavior

Hanuman langurs are not particularly territorial, but they claim a grazing area of ​​0.1 to 22 km². The size of the grazing area essentially depends on the size of the group, the type of habitat and the quality of the habitat. In the vicinity or in human settlements, the grazing areas are extremely small, as food is always available in abundance. Depending on the species and the amount of food in the area, Hanuman langurs move between 500 and 1,500 meters per day. The following applies: the lower the amount of food, the longer the distances covered per day.

Occurrence and habitat

distribution

The distribution area of ​​the Hanuman langurs extends over India, Bangladesh, Bhutan, China, Nepal, Afghanistan and Pakistan. In northern India the distribution area extends to the foothills of the Himalayas. Here Hanuman langurs could also be detected in Bhutan, Tibet and Nepal. In the south, individual species are distributed as far as southern India and Sri Lanka (Groves, 2001).

habitat

Hanuman langurs are not picky about their choice of habitat. They are therefore found in numerous habitat types. Hanuman langurs, however, avoid dense tropical rainforests. They occur both on the plain and at altitudes of up to 4,000 meters above sea level. The preferred habitats include light deciduous forests, subtropical and temperate coniferous forests, wooded river banks, Mediterranean hard-leaf vegetation zones, parks, but also bushland, temple-related areas, agricultural areas, plantations, villages and cities. Proximity to people is by no means avoided. Even in some megacities such as Jodhpur in the Indian state of Rajasthan, they feel comfortable and have adapted to people (Davies, 1994; Bennett & Davies, 1994). Due to the large distribution area, the annual amount of precipitation varies between 100 and 2,000 millimeters, depending on the habitat. Only a few species live in extremely moist deciduous forests. The Dussumier Hanuman Langur is one of the few species that can also be found in damp habitats (Semnopithecus dussumieri). In the subalpine regions in the area of ​​2,000 meters above sea level, temperatures can drop to -7 ° C. In summer the temperatures rise to 35 ° C, locally up to 46 ° C.

Biocenosis

Sympathy

Hanuman langurs live sympatricly in association with other primates such as Nilgirilanguren (Trachypithecus johnii) or various macaques (Macaca) Choudhury, 2008). Among the macaques, these are mainly rhesus monkeys (Macaca mulatta) or gray arm macaque (Macaca ochreata). Under trees where Hanuman langurs eat, other animals such as cattle and deer benefit from fallen fruits or leftovers from the langurs.

Predators

The Hanuman langurs are natural enemies Cats (Felidae) and Dogs (Canidae) such as tiger (Panthera tigris), Leopards (Panthera pardus), Wolves (Canis lupus), Golden jackal (Canis aureus) or red dog (Cuon alpinus). Hanuman langurs have nothing to oppose these predators and take refuge in trees. Now and then grab it too Snakes (Serpentes) against which Hanuman langurs can defend themselves collectively (Srivastava, 1991; Ross, 1993).

nutrition

Hanuman langurs feed mainly on plant-based food. They mostly eat leaves, mostly young, and more rarely also ripe leaves. However, the food consumed varies depending on occurrence, habitat and season. In human settlements or cities, the Hanuman langurs have adapted their diet to humans. In natural habitats, around 50 to 60% of the food is made up of leaves, fruits 15 to 25%, flowers and buds 4 to 13% and animal food in the form of insects (Insecta), Insect larvae and other small arthropods (Arthropoda) 1 to 3% (Koenig & Borries, 2001). In field studies by various researchers such as Sayers & Norconk (2008), Chalise (1994) and others, more than 200 plant species could be identified that could be used as fodder crops. In addition to leaves, herbs and grasses, mosses and lichens, seeds and young shoots are also eaten to a small extent. Nightshade (Solanum), Cabbage (Brassica), Spinach (Spinacia), Eggplant (Solanum melongena) and eaten grain. The water requirement is met mainly through food, but Hanuman langurs also drink water when it is available.

Reproduction

Under favorable conditions, sexual maturity is reached at the age of a good 3 years. The mating season extends throughout the year in most regions, especially in the tropical and subtropical regions. In temperate and subalpine regions, the mating season extends over the warm season (Newton, 1987). Both groups with one male and groups with several males occur in the Hanuman langurs. The mating behavior can be described as polygamous, since there are no monogamous structures. There is a strict hierarchy among the females in a group. The higher a female is in the hierarchy, the greater the reproductive success. During receptivity, females show no external signs of willingness to mate. It is assumed that such a possible infanticide by males is to be prevented. Infanticide is relatively common among the Hanuman langurs. How the males determine the receptivity is largely unclear. (Ostneret al., 2006; Borrieset al., 1991). Depending on the species, according to Agoramoorthy (1993), up to around a quarter of newborns are killed by males. Dominant males thus ensure greater reproductive success. The mating behavior comes from the females. They literally offer themselves to the males. This is accompanied by a trembling head, lowered tail and holding out the analog title region. The copulation takes place in the middle of a group. The mating is therefore often disturbed and interrupted. (Summeret al. 2006).

The females cycle lasts about 24 days. There is usually about 16 to 17 months between births. After a gestation period of 195 to 205 (200) days, a female gives birth to a young. The births usually take place under cover of darkness. The offspring already has a light brown, tail-brown or black fur at birth. The visible skin is pale, mostly flesh-colored. In the first time, but at least in the first few weeks of life, a young animal clings to the mother's belly. At first there is no further locomotion apart from this clamp and the sucking reflex. If they are hungry, the infants make themselves noticeable by squeaking or screaming noises. The young animals learn quadrupedal locomotion starting at the age of two months. The boys gain their first jumping experience at the age of 3 or 4 months. In the first year of life, the young always stay near the mother. The young are also looked after by other females in the group. Males, on the other hand, have nothing to do with rearing. Occasionally, young animals are abducted by females from other groups. However, the offspring can only survive until the fourth month of life if the thief has breast milk. Complete weaning from breast milk occurs between 8.5 and 12 months of age. Young males leave the birth group when they reach sexual maturity, females remain in their genealogical group for life. The mortality among the boys is very high. Hardly a third of all young animals reach sexual maturity. Life expectancy in captivity is a good 30 years (Weigl, 2005).

Ecology, hazard and protection

All species of Hanuman langurs are listed in Appendix I of the Washington Convention on Endangered Species. However, the degree of endangerment of the individual species is very different. The Kashmir Hanuman Langur is considered endangered (EN, Endangered) (Semnopithecus ajax), as endangered (VU, Vulnerable) the black-footed Hanuman langur (Semnopithecus hypoleucos). The Tarai Hanuman Langur (Semnopithecus hector) and the Southern Hanuman Langur (Semnopithecus priam) are on the pre-warning list (NT, Near Threatened). The remaining 3 species, i.e. the Dussumier Hanuman Langur (Semnopithecus dussumieri), the Bengali Hanuman langur (Semnopithecus entellus) and the Nepalese Hanuman langur (Semnopithecus schistaceus) are not considered to be at risk (LC, Least Concern). In India the animals are under protection, the killing and catching of Hanuman langurs is prohibited. However, paper is patient. In some regions humans chase after animals and young animals in particular often end up in the illegal pet trade.

The greatest threat today comes from the destruction of natural habitats. But also the high mortality as well as hunting and persecution represent a very great danger. Today, through logging and slash and burn, gigantic areas on the Indian subcontinent are being converted into agricultural areas. Large monocultures arise in the form of plantations and other agricultural areas. In some regions, forests are also being sacrificed to open-cast mining or turned into rubbish dumps. It is not uncommon for herds of cattle to be herded in sparse forests. Hanuman langurs are often kept as pets and can therefore be bought at every weekly market. Both catching and buying are prohibited, but there is a lack of enforcement of the law. Hanuman langurs are also not infrequently kept in temples. The animals are occasionally used as experimental animals in medical research (Choudhury, 2001; Bhatnagar, 2001; Ahmed, 2001, 2004). Hanuman langurs are tolerated and even fed in human settlements and cities. However, wrong food often leads to death. Further deaths occur in road traffic or on power lines. In agriculture, Hanuman langurs can cause great damage when they appear in large numbers. Since many Indians consider the animals to be sacred, they are not persecuted as crop pests.

Systematics of the Hanuman langurs

Image: Schwarzfüßiger-Hanuman-Langur-1223.jpg Genus: Hanuman langurs (Semnopithecus)

Type: Cashmere Hanuman Langur (Semnopithecus ajax)
Species: Dussumier Hanuman Langur (Semnopithecus dussumieri)
Species: Bengali Hanuman Langur (Semnopithecus entellus)
Species: Tarai Hanuman Langur (Semnopithecus hector)
Type: Black-footed Hanuman Langur (Semnopithecus hypoleucos)
Species: Southern Hanuman Langur (Semnopithecus priam)
Species: Nepalese Hanuman Langur (Semnopithecus schistaceus)

The assignment of the two types below is considered controversial and is currently being discussed. Groves (2005) lists both species in the crested langur genus (Trachypithecus). Wilson & Reeder (2005) also share his opinion.

Type: Nilgirilangur (Semnopithecus johniiorTrachypithecus johnii)
Type: Whitebeard Langur (Semnopithecus vetulusorTrachypithecus vetulus)

attachment

See also

Literature and sources

Genre-specific sources
  • Ronald M. Nowak: Walker's Mammals of the World: v. 1 & 2. B&T, edition 6, 1999, (engl.) ISBN 0801857899
  • Don E. Wilson & DeeAnn M. Reeder: Mammal Species of the World, a Taxonomic & Geographic Reference. J. Hopkins Uni. Press, 3rd ed., 2005 ISBN 0801882214
  • Thomas Geissmann: Comparative primatology. Springer Verlag, 2003, ISBN 3540436456
  • David Macdonald: The great encyclopedia of mammals. Ullmann / tandem ISBN 3833110066
  • Hans Petzsch: Urania Animal Kingdom, 7 Vols., Mammals. Urania, Stuttgart (1992) ISBN 3332004999
  • Mammals. 700 species in their habitats. Dorling Kindersley, 2004. ISBN 383100580X
  • Martin Osterholz, Lutz Walter & Christian Roos: Phylogenetic position of the langur genera Semnopithecus and Trachypithecus among Asian colobines, and genus affiliations of their species groups. BMC Evolutionary Biology, 2008
Species-specific sources

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