Diana Monkey
Encyclopedia
The Diana monkey is an Old World monkey
found in West Africa
, from Sierra Leone
to Côte d'Ivoire
.
The Diana monkey ranges from 40 to 55 cm in length, excluding its tail, which is of a uniform 3–4 cm diameter and 50–75 cm long. Adults weigh between 4–7 kg
. Individual Diana monkeys may live for up to 20 years.
They are generally black or dark grey, but have a white throat, crescent-shaped browband, ruff and beard; the browband gave the species its common name, since it was held to resemble the bow of the goddess Diana. The monkeys' underarms are also white, and they have a white stripe down their thighs, while the backs of their thighs, and their lower backs, are a chestnut colour. Apart from the browband, ruff and beard, and some fringes on their limbs, their fur is short and sleek in appearance.
Like most primates, Diana monkeys can always carry diseases that can be communicated to humans, like yellow fever
and tuberculosis
, but they are not important carriers of these. The species is regarded as vulnerable
by the IUCN as well as by the United States Fish and Wildlife Service
, the chief dangers to them being habitat destruction (they are now virtually confined to coastal areas) and hunting for bushmeat.
Two taxa formerly considered subspecies
of the Diana monkey have recently been elevated to full species status: the Roloway monkey
(C. roloway) is found in Côte d'Ivoire and Ghana
, and the Dryas monkey
(C. dryas) found in the DR Congo.
, and the Common Chimpanzee
and humans.
The Diana monkey is a noisy presence in the forest. Its marked coloration allows a wide range of visual social signals, and it also has a wide range of alarm call
s, with different sounds for different predators. The monkey has distinctive alarm calls for different kinds of predators, and recent research has shown that other forest residents such as the Yellow-casqued Hornbill
are able to discriminate these and take appropriate action.
Groups consist of a single male with a number of reproducing females and their infants. In good conditions, adult females reproduce annually. Gestation
lasts about 5 months, and the young nurse for a further 6 months. Normally only a single infant is born. Although the young are born in a fairly well developed condition, with open eyes and able to grasp their mother, at least in zoo conditions Diana monkey mothers appear anxious and possessive, rarely letting young infants leave them. As infants grow, however, they become very playful. Juveniles reach sexual maturity at an age of about 3 years. Daughters remain in their mothers' social groups, while males leave their natal groups shortly before attaining sexual maturity.
Old World monkey
The Old World monkeys or Cercopithecidae are a group of primates, falling in the superfamily Cercopithecoidea in the clade Catarrhini. The Old World monkeys are native to Africa and Asia today, inhabiting a range of environments from tropical rain forest to savanna, shrubland and mountainous...
found in West Africa
West Africa
West Africa or Western Africa is the westernmost region of the African continent. Geopolitically, the UN definition of Western Africa includes the following 16 countries and an area of approximately 5 million square km:-Flags of West Africa:...
, from Sierra Leone
Sierra Leone
Sierra Leone , officially the Republic of Sierra Leone, is a country in West Africa. It is bordered by Guinea to the north and east, Liberia to the southeast, and the Atlantic Ocean to the west and southwest. Sierra Leone covers a total area of and has an estimated population between 5.4 and 6.4...
to Côte d'Ivoire
Côte d'Ivoire
The Republic of Côte d'Ivoire or Ivory Coast is a country in West Africa. It has an area of , and borders the countries Liberia, Guinea, Mali, Burkina Faso and Ghana; its southern boundary is along the Gulf of Guinea. The country's population was 15,366,672 in 1998 and was estimated to be...
.
The Diana monkey ranges from 40 to 55 cm in length, excluding its tail, which is of a uniform 3–4 cm diameter and 50–75 cm long. Adults weigh between 4–7 kg
Kilogram
The kilogram or kilogramme , also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram , which is almost exactly equal to the mass of one liter of water...
. Individual Diana monkeys may live for up to 20 years.
They are generally black or dark grey, but have a white throat, crescent-shaped browband, ruff and beard; the browband gave the species its common name, since it was held to resemble the bow of the goddess Diana. The monkeys' underarms are also white, and they have a white stripe down their thighs, while the backs of their thighs, and their lower backs, are a chestnut colour. Apart from the browband, ruff and beard, and some fringes on their limbs, their fur is short and sleek in appearance.
Like most primates, Diana monkeys can always carry diseases that can be communicated to humans, like yellow fever
Yellow fever
Yellow fever is an acute viral hemorrhagic disease. The virus is a 40 to 50 nm enveloped RNA virus with positive sense of the Flaviviridae family....
and tuberculosis
Tuberculosis
Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...
, but they are not important carriers of these. The species is regarded as vulnerable
Vulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
by the IUCN as well as by the United States Fish and Wildlife Service
United States Fish and Wildlife Service
The United States Fish and Wildlife Service is a federal government agency within the United States Department of the Interior dedicated to the management of fish, wildlife, and natural habitats...
, the chief dangers to them being habitat destruction (they are now virtually confined to coastal areas) and hunting for bushmeat.
Two taxa formerly considered subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of the Diana monkey have recently been elevated to full species status: the Roloway monkey
Roloway Monkey
The Roloway monkey is a species of Old World monkey found in a small area of eastern Côte d'Ivoire and the forests of Ghana, between the Sassandra and Pra Rivers....
(C. roloway) is found in Côte d'Ivoire and Ghana
Ghana
Ghana , officially the Republic of Ghana, is a country located in West Africa. It is bordered by Côte d'Ivoire to the west, Burkina Faso to the north, Togo to the east, and the Gulf of Guinea to the south...
, and the Dryas monkey
Dryas Monkey
The Dryas monkey , also known as Salonga monkey or ntolu, is a little-known species of guenon found only in the Congo Basin, restricted to the left bank of the Congo River. It is now established that the animals previously classified as Cercopithecus salongo were in fact Dryas monkeys...
(C. dryas) found in the DR Congo.
Habitat, behavior, and reproduction
The Diana monkey is found in the primeval forests, and does not thrive in secondary forests. It is active during the day. It feeds at all levels of the canopy, rarely comes down to the ground. Diana monkeys retreat to the upper levels of the trees at night, though they do not make nests. They feed mainly on fruit and insects, but will also take flowers, young leaves and invertebrates, and are in turn preyed on by the Crowned Hawk-eagle, the LeopardLeopard
The leopard , Panthera pardus, is a member of the Felidae family and the smallest of the four "big cats" in the genus Panthera, the other three being the tiger, lion, and jaguar. The leopard was once distributed across eastern and southern Asia and Africa, from Siberia to South Africa, but its...
, and the Common Chimpanzee
Common Chimpanzee
The common chimpanzee , also known as the robust chimpanzee, is a great ape. Colloquially, the common chimpanzee is often called the chimpanzee , though technically this term refers to both species in the genus Pan: the common chimpanzee and the closely related bonobo, formerly called the pygmy...
and humans.
The Diana monkey is a noisy presence in the forest. Its marked coloration allows a wide range of visual social signals, and it also has a wide range of alarm call
Alarm call
In the field of animal communication, an alarm signal is an antipredator adaptation referring to various signals emitted by social animals in response to danger. Many primates and birds have elaborate alarm calls for warning conspecifics of approaching predators. For example, the characteristic...
s, with different sounds for different predators. The monkey has distinctive alarm calls for different kinds of predators, and recent research has shown that other forest residents such as the Yellow-casqued Hornbill
Yellow-casqued Hornbill
The Yellow-casqued Wattled Hornbill , also known as the Yellow-casqued Hornbill, is found in the rainforest of coastal regions of West Africa, for example in Côte d'Ivoire....
are able to discriminate these and take appropriate action.
Groups consist of a single male with a number of reproducing females and their infants. In good conditions, adult females reproduce annually. Gestation
Gestation
Gestation is the carrying of an embryo or fetus inside a female viviparous animal. Mammals during pregnancy can have one or more gestations at the same time ....
lasts about 5 months, and the young nurse for a further 6 months. Normally only a single infant is born. Although the young are born in a fairly well developed condition, with open eyes and able to grasp their mother, at least in zoo conditions Diana monkey mothers appear anxious and possessive, rarely letting young infants leave them. As infants grow, however, they become very playful. Juveniles reach sexual maturity at an age of about 3 years. Daughters remain in their mothers' social groups, while males leave their natal groups shortly before attaining sexual maturity.