More human than we care to admit….
The most widespread of all Indian Primates, the Rhesus Macaque or Rhesus Monkey is the common monkey of India, living in close association with humans. This species is listed as ‘Least Concern’ in view of its wide distribution, presumed large population, is tolerant of a broad range of habitats
About the Species
The Rhesus Macaque is covered in thick brownish-grey fur, tints varying from very thick and dark in Kashmir to sparse and sandy brown in Rajasthan. A consistent feature across geographies is the organgish tint to the fur along the loins and hind quarters, distinguishing it from the similar looking Assamese Macaque. It carries its medium sized tail erect with a slight bend at the tip. Males are larger than females. Males grow up to 21 inches (53 cm) long and tip the scales at 17 pounds (7.7 kg.) Females only grow to 19 inches (47 cm) and weigh an average of 12 pounds (5.3 kg.) Both males and females can store food in pouches which are similar to a hamster’s cheek pouches but not quite so dramatic. The females can be easily recognized by a pair of mamma, a distinct feature in all primates.Infants are born with pink faces which change to the usual flesh coloured in two months’ time.
Origins and habitat
The species as a whole is found throughout most of southern Asia, in eastern Afghanistan, Bangladesh, Bhutan, central and southern China, Lao PDR, Myanmar, Nepal, northern Pakistan, northern Thailand, and Vietnam, northern and central India. The upper altitude for existence is 400 metres. Sizable populations are found in south, southeast and east Asia. Populations are becomingincreasingly commensal with humans. There are introduced populations (mostly not mapped) in areas within this region as well as outside it, for instance south of the Krishna River in India, Hong Kong and United States.
A habitat generalist, its favoured habitat varies greatly, from temperate coniferous, moist and dry deciduous, bamboo, and mixed forests, mangroves, scrub, rainforest, and around human habitations and developments, including cultivated areas, temples, and roadsides.
This species is diurnal and omnivorous, and alternatively arboreal and terrestrial.They are quadrupedal and, when on the ground, they walk digitigrade. Their main source of food is from seeds, roots, bark, cereals and fruits. Though they do not show a preference for meat, at times, they have been known to eat beetles, ants, terminate and even grasshoppers but this is when the food sources have dried up completely. They have larger cheek pouches which they use in order to store up food when they are out foraging.Some rhesus macaques are also known to eat dirt since the soil there is rich in minerals that are good for treating upset stomach. They can swim and are quite good and even younger monkeys that are days old, they can swim.
Highly social creatures, the Rhesus monkeys live in group sized ranging from 20 to 200! Every monkey in the troop will have their place within the group, have their own ranking. Though it is the males that outrank the female monkeys, the ranking is separate. Females tend not to leave the social group, and have highly stable matrilineal hierarchies in which a female’s rank is dependent on the rank of her mother.In the group, macaques position themselves based on rank. The “central male subgroup” contains the two or three oldest and most dominant males which are codominant, along with females, their infants, and juveniles. This subgroup occupies the center of the group and determines the movements, foraging, and other routines.The females of this subgroup are also the most dominant of the entire group. The farther to the periphery a subgroup is, the less dominant it is.Rhesus macaques interact using a variety of facial expressions, vocalizations, body postures, and gestures. Perhaps the most common facial expression the macaque makes is the “silent bared teeth” face, macaques also make “coos” and “grunts”. These are also made during affiliative interactions, and approaches before grooming. breeding period can last up to 11 days, and a female usually mates with four males during that time. Male rhesus macaques have not been observed to fight for access to sexually receptive females
- Self-Awareness: In several experiments giving mirrors to rhesus monkeys, they looked into the mirrors and groomed themselves as well as flexed various muscle groups. This behaviour indicates that they recognised and were aware of themselves.
- Cognitive intelligence: In psychologicalresearch, rhesus macaques have demonstrated a variety of complex cognitive abilities, including the ability to make same-different judgments, understand simple rules, and monitor their own mental states and display self-awareness. In 2014, onlookers at a train station in Kanpur, India, documented a rhesus monkey, knocked unconscious by overhead power lines that was revived by another rhesus that systematically administered a series of resuscitative actions!
- The Rhesus Monkey is a charismatic and fun-loving creature; they can be very cheeky, often seen trying to pull off pranks on each other!
- A young / baby of a rhesus monkey is called an ‘infant’, pretty similar to a human baby! A rhesus monkey group is called a ‘troop, barrel, tribe or cartload’.
More human than we care to admit….
The most widely spread langur in India, S. entellus or the grey langur are a group of Old World monkeys constituting the entirety of the genus Semnopithecus. It is listed by IUCN as Least Concern in view of its wide distribution, tolerance of a broad range of habitats.
About the Species
The grey langur is covered in yellowish-brown or pale orange fur with buff on the chest. It is black pawed upto the wrist and has a forward looped tail. This forward-looped tail is the distinguishing feature compared to the langurs of the south, which have a backward looped tail. Also, it differs from the Himalayan langur – being smaller and more orangish in colour than the more greyish-black backed Himalayan Langur.
The head-and-body length is from 20 to 31 inches and their tails, at 27 to 40 inches are always longer than their bodies. The average weight of grey langurs is 18 kg (40 lb) in the males and 11 kg (24 lb) in the females. They mostly walk quadrupedal, make bipedal hops and leaps to reach far flung places. Males are larger than females and the new born are pink in colour.
The authors of Mammal Species of the World* recognize the following seven species of Semnopithecus. One member from Sri Lanka moved to the genus from Trachypithecus. The total becomes eight now as follows:
|Semnopithecus schistaceus||Nepal Grey Langur||endemic to the Himalayas in Nepal, far southwestern China (Tibet), northern India, northern Pakistan, Bhutan and possibly Afghanistan||Least Concern|
|Semnopithecus ajax||Kashmir Grey Langur||northern India west into Pakistani Kashmir and in Nepal||Endangered|
|Semnopithecus hector||Terai Grey Langur||native to Bhutan, northern India and Nepal||Near Threatened|
|Semnopithecus entellus||Northern Plains Grey Langur||lowlands north of the Godavari and Krishna rivers and south of the Ganges||Least Concern|
|Semnopithecus hypoleucos||Black footed Grey Langur||South West India- Goa, Karnataka and Kerala||Vulnerable|
|Semnopithecus dussumieri||Southern Plains Grey Langur||south west and west central India||Least Concern|
|Semnopithecus priam||Tufted Grey Langur||southeast India and Sri Lanka||Near Threatened|
|Semnopithecus vetulus||Purple faced Langur||Sri Lanka||Endangered|
Origins and habitat
The species occurs in western Bangladesh and eastern India (in Andhra Pradesh, Bengal, Bihar, Chhattisgarh, Jharkhand, Madhya Pradesh, Maharashtra, Orissa, and West Bengal. It is absent in major parts of Saurashtra and Kutch in Gujarat.
By habit, it is mainly terrestrial and folivorous. Habitat is highly variable, the grey langur is found in almost all habitats except desert, though it shows a preference for dry, deciduous scrub. It is commonly found near human settlements.
The grey langur is diurnal in nature and highly arboreal by habit. It is often found feeding on leaves, flowers, fruits and berries on the tree tops. They are programmed to eat rapidly, often indiscriminately, depending upon bacteria in their fore-stomachs to break down any toxins they may have ingested. This is perhaps the reason for the wide success and distribution of this species. They also obtain salt, mineral and trace elements by licking rocks, termite mounds and salt lick. Most feeding activity takes place in the morning and late afternoon.
Langur live in troops that vary from 8 – 20 animals, has a mixed composition of all ages and sexes and is led by a dominant male. Being highly social creatures with well-defined social structures, the hotter part of the day is spent by troop members grooming each other; this activity serves the purpose of cleaning one other, reinforcing bonds and establishing the social hierarchy. Gestation lasts for 6 months, generally one young is born and new babies become the centre of attention of the female groups, many of them vying with each other to touch and handle the new born. They grow rapidly on a variety of diet, are weaned between 10-15 months and by two years of age cut bonds with their mother to establish a new life.
- They share a unique friendship with Chital or spotted deer. As they gorge on the leaves on the tree-tops, they watch out for any approaching predators and warn the deer with alarm calls. Also, they intentionally drop fresh leaves as for deer to feed on. So much so for a shared meal!
- The coughing alarm call of the Langur is often the first indicator of the presence of a predator
- They generally have a favorite roosting tree, to which the animals retire at the end of the day, calling it their home!