Black-and-white colobus

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Black-and-white colobus [1]
Colubusmonkey.JPG
Mantled guereza (Colobus guereza)
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Haplorhini
Infraorder: Simiiformes
Family: Cercopithecidae
Subfamily: Colobinae
Tribe: Colobini
Genus: Colobus
Illiger, 1811
Type species
Simia polycomos
Schreber, 1800
(Cebus polykomos Zimmermann, 1780)
Species
See text

Black-and-white colobuses (or colobi) are Old World monkeys of the genus Colobus, native to Africa. They are closely related to the red colobus monkeys of genus Piliocolobus . [1] There are five species of this monkey, and at least eight subspecies. [1] They are generally found in high-density forests where they forage on leaves, flowers and fruit. Social groups of colobus are diverse, varying from group to group. [2] Resident-egalitarian and allomothering relationships have been observed among the female population. [3] Complex behaviours have also been observed in this species, including greeting rituals [2] and varying group sleeping patterns. [4] Colobi play a significant role in seed dispersal.

Contents

Etymology

The word "colobus" comes from Greek κολοβός (kolobós, "docked", "maimed"), so named because the thumb is stump-like.

Taxonomy

Genus Colobus Illiger, 1811 – five species
Common nameScientific name and subspeciesRangeSize and ecologyIUCN status and estimated population
Angola colobus

Colobus angolensis.jpg

C. angolensis
P. L. Sclater, 1860

Six subspecies
  • C. a. angolensis (Sclater's Angola colobus)
  • C. a. cordieri (Cordier's Angola colobus)
  • C. a. cottoni (Powell-Cotton's Angola colobus)
  • C. a. palliates (Tanzanian black-and-white colobus)
  • C. a. prigoginei (Prigogine's Angola colobus)
  • C. a. ruwenzorii (Ruwenzori colobus)
  • C. a. sharpei (Sharpe's Angola Colobus)
Central Africa
Angola Colobus area.png
Size: 49–68 cm (19–27 in) long, plus 70–83 cm (28–33 in) tail [5]

Habitat: Forest [6]

Diet: Leaves, as well as stems, bark, flowers, buds, shoots, fruits, and insects [5]
 VU 


Unknown Decrease2.svg [6]

Black colobus

1 - Colobus polykomos 2 - Colobus satanas.jpg

C. satanas
Waterhouse, 1838

Two subspecies
  • C. s. anthracinus (Gabon black colobus)
  • C. s. satanas (Bioko black colobus)
Western Africa
Black Colobus area.png
Size: 50–70 cm (20–28 in) long, plus 62–88 cm (24–35 in) tail [7]

Habitat: Forest [8]

Diet: Nuts and seeds, as well as unripe fruit and leaves [7]
 VU 


Unknown Decrease2.svg [8]

King colobus

King colobus monkeys.jpg

C. polykomos
(Zimmermann, 1780)
Western Africa
King Colobus area.png
Size: 45–72 cm (18–28 in) long, plus 52–100 cm (20–39 in) tail [9]

Habitat: Forest and savanna [10]

Diet: Leaves, as well as fruit and flowers [9]
 EN 


Unknown Decrease2.svg [10]

Mantled guereza

Mantled Guereza.jpg

C. guereza
Rüppell, 1835

Seven subspecies
  • C. g. caudatus (Kilimanjaro guereza)
  • C. g. dodingae (Dodinga Hills guereza)
  • C. g. guereza (Omo River guereza)
  • C. g. kikuyuensis (Eastern black-and-white colobus)
  • C. g. matschiei (Mau Forest guereza)
  • C. g. occidentalis (Western guereza)
  • C. g. percivali (Mt Uaraguess guereza)
Central Africa
Mapa distribucion Colobus guereza.png
Size: 45–72 cm (18–28 in) long, plus 52–100 cm (20–39 in) tail [11]

Habitat: Forest [12]

Diet: Leaves, as well as fruit, buds, and blossoms [11]
 LC 


Unknown Decrease2.svg [12]

Ursine colobus

Colobus vellerosus 12785335.jpg

C. vellerosus
(I. Geoffroy, 1834)
Western Africa
Colobus vellerosus distribution.svg
Size: 60–67 cm (24–26 in) long, plus 73–93 cm (29–37 in) tail [13]

Habitat: Forest [14]

Diet: Leaves and seeds, as well as fruit, insects, and clay [15]
 CR 


975 Decrease2.svg [14]

Fossil species

Behaviour and ecology

A multi-male unit of Angolan colobus in a multilevel society Multi-male unit of Rwenzori colobus in Nyungwe .jpg
A multi-male unit of Angolan colobus in a multilevel society

Colobus habitats include primary and secondary forests, riverine forests, and wooded grasslands; they are found more in higher-density logged forests than in other primary forests. Their ruminant-like digestive systems have enabled them to occupy niches that are inaccessible to other primates: they are herbivorous, eating leaves, fruit, flowers, lichen, herbaceous vegetation and bark. Colobuses are important for seed dispersal through their sloppy eating habits, as well as through their digestive systems.

Leaf toughness influences colobus foraging efficiency. Tougher leaves correlate negatively with ingestion rate (g/min) as they are costly in terms of mastication, but positively with investment (chews/g). [16] Individuals spend approximately 150 minutes actively feeding each day. [16] In a montane habitat colobus are known to utilise lichen as a fallback food during periods of low food availability. [17]

Social patterns and morphology

Colobuses live in territorial groups that vary in both size (3-15 individuals) and structure. [2] [18] [19] It was originally believed that the structure of these groups consisted of one male and about 8 female members. [20] However, more recent observations have shown variation in structure and the number of males within groups, with one species forming multi-male, multifemale groups in a multilevel society, and in some populations supergroups form exceeding 500 individuals. [18] [19] There appears to be a dominant male, whilst there is no clear dominance among female members. [2] Relationships among females are considered to be resident-egalitarian, as there is low competition and aggression between them within their own groups. Juveniles are treated as a lower-rank (in regards to authority) than subadults and likewise when comparing subadults to adults. [3] Colobuses do not display any type of seasonal breeding patterns. [21]

As suggested by their name, adult colobi have black fur with white features. White fur surrounds their facial region and a "U" shape of long white fur runs along the sides of their body. Newborn colobi are completely white with a pink face. Cases of allomothering are documented, which means members of the troop other than the infant's biological mother care for it. Possible explanations to this are, increasing inclusive fitness or maternal practice which will benefit future offspring. [22]

Social behaviours

Angolan black-and-white colobus with infant. Angolan colobus with infant.jpg
Angolan black-and-white colobus with infant.

Many members participate in a greeting ritual when they are reunited with familiar individuals, an act of reaffirming. [2] The greeting behaviour is generally carried out by the approaching monkey and often is followed with grooming. They participate in three greeting behaviours of physical contact. This includes mounting, head mounting (grasps the shoulders) and embracing. [2] It seems as though these behaviours do not have any relationship with mating or courting. [2]

Adult Eastern black-and-white colobus with a juvenile Eastern black-and-white colobus (Colobus guereza occidentalis) with juvenile.jpg
Adult Eastern black-and-white colobus with a juvenile

Black-and-white colobus have complex sleeping patterns. They sleep in trees near a food source, which may serve to save energy. [4] Groups seem to regularly switch up sleeping locations (suggested due to reducing risk of parasites and placement prediction) and generally do not sleep near other groups. They also tend to sleep more tightly together on nights with great visibility. [4] They sleep in mid- to upper sections of tall trees which allows for predator watch as well as protection from ground and aerial predators while they are asleep. [4] Although there is no obvious preference for tree type, they have often been observed in Antiaris toxicaria. [4]

Conservation

They are prey for many forest predators such as leopards and chimpanzees,[ citation needed ] and are threatened by hunting for the bushmeat trade, logging, and habitat destruction.

Individuals are more vigilant (conspecific threat) in low canopy, they also spend less time scanning when they are around familiar group members as opposed to unfamiliar. [23] There are no clear difference in vigilance between male and females. However, there is a positive correlation between mean monthly vigilance and encounter rates. [23] Male vigilance generally increases during mating. [24]

Related Research Articles

<span class="mw-page-title-main">Chimpanzee</span> Great ape native to the forest and savannah of tropical Africa

The chimpanzee, also simply known as the chimp, is a species of great ape native to the forests and savannahs of tropical Africa. It has four confirmed subspecies and a fifth proposed one. When its close relative the bonobo was more commonly known as the pygmy chimpanzee, this species was often called the common chimpanzee or the robust chimpanzee. The chimpanzee and the bonobo are the only species in the genus Pan. Evidence from fossils and DNA sequencing shows that Pan is a sister taxon to the human lineage and is thus humans' closest living relative. The chimpanzee is covered in coarse black hair, but has a bare face, fingers, toes, palms of the hands, and soles of the feet. It is larger and more robust than the bonobo, weighing 40–70 kg (88–154 lb) for males and 27–50 kg (60–110 lb) for females and standing 150 cm.

<span class="mw-page-title-main">Primate</span> Order of mammals

Primates is an order of mammals, which is further divided into the strepsirrhines, which include lemurs, galagos, and lorisids; and the haplorhines, which include tarsiers; and the simians, which include monkeys and apes. Primates arose 85–55 million years ago first from small terrestrial mammals, which adapted for life in tropical forests: many primate characteristics represent adaptations to the challenging environment among tree tops, including large brain sizes, binocular vision, color vision, vocalizations, shoulder girdles allowing a large degree of movement in the upper limbs, and opposable thumbs that enable better grasping and dexterity. Primates range in size from Madame Berthe's mouse lemur, which weighs 30 g (1 oz), to the eastern gorilla, weighing over 200 kg (440 lb). There are 376–524 species of living primates, depending on which classification is used. New primate species continue to be discovered: over 25 species were described in the 2000s, 36 in the 2010s, and six in the 2020s.

<span class="mw-page-title-main">Old World monkey</span> Family of mammals

Old World monkeys are primates in the family Cercopithecidae. Twenty-four genera and 138 species are recognized, making it the largest primate family. Old World monkey genera include baboons, red colobus and macaques. Common names for other Old World monkeys include the talapoin, guenon, colobus, douc, vervet, gelada, mangabey, langur, mandrill, surili (Presbytis), patas, and proboscis monkey.

<span class="mw-page-title-main">Zanzibar red colobus</span> Species of Old World monkey

The Zanzibar red colobus is a species of red colobus monkey endemic to Unguja, the main island of the Zanzibar Archipelago, off the coast of Tanzania. It is also known as Kirk's red colobus after Sir John Kirk, the British Resident of Zanzibar who first brought it to the attention of zoological science. It is now classified as an endangered species and in the mid-1990s was adopted as the flagship species for conservation in Zanzibar. The population is still decreasing, and conservationists are attempting to work with the local government to devise a proper, effective strategy to protect the population and habitat. Challenges include the species' habitat, which is limited to the archipelago. The species has been reclassified three times; it was previously in the genus Colobus, then in the genus Procolobus, and later in the genus Piliocolobus.

<span class="mw-page-title-main">King colobus</span> Species of Old World monkey

The king colobus, also known as the western black-and-white colobus, is a species of Old World monkey, found in lowland and mountain rainforests in a region stretching from Senegal, through Guinea-Bissau, Guinea, Sierra Leone and Liberia to the Ivory Coast. One of five members of the genus Colobus, the black-and-white colobuses, the king colobus is the westernmost species of the group on the continent of Africa. It eats mainly leaves, but also fruits and flowers. Though it is arboreal, it eats primarily on the ground. It lives in small groups consisting of 3 to 4 females and 1 to 3 males, plus their young. These groups maintain distance from one another through territorial calling.

<span class="mw-page-title-main">Sooty mangabey</span> Species of mammal

The sooty mangabey is an Old World monkey found in forests from Senegal in a margin along the coast down to the Ivory Coast.

<span class="mw-page-title-main">Mantled guereza</span> Species of mammal

The mantled guereza, also known simply as the guereza, the eastern black-and-white colobus, or the Abyssinian black-and-white colobus, is a black-and-white colobus, a type of Old World monkey. It is native to much of west central and east Africa, including Cameroon, Equatorial Guinea, Nigeria, Ethiopia, Kenya, Tanzania, Uganda and Chad. The species consists of several subspecies that differ in appearance. It has a distinctive appearance, which is alluded to in its name; the long white fringes of hair that run along each side of its black trunk are known as a mantle. Its face is framed with white hair and it has a large white tail tuft.

<span class="mw-page-title-main">Red colobus</span> Genus of Old World monkeys

Red colobuses are Old World monkeys of the genus Piliocolobus. It was formerly considered a subgenus within the genus Procolobus, which is now restricted to the olive colobus. They are closely related to the black-and-white colobus monkeys, and some species are often found in groups with the blue monkey. The western red colobus is frequently hunted by the common chimpanzee.

<span class="mw-page-title-main">Tufted capuchin</span> Species of New World monkey

The tufted capuchin, also known as brown capuchin, black-capped capuchin, or pin monkey, is a New World primate from South America and the Caribbean islands of Trinidad and Margarita. As traditionally defined, it is one of the most widespread primates in the Neotropics, but it has recently been recommended considering the black-striped, black and golden-bellied capuchins as separate species in a new genus, thereby effectively limiting the tufted capuchin to the Amazon basin and nearby regions. However, the large-headed capuchin (S. a. macrocephalus), previously defined as a distinct species, has been reclassified as a subspecies of the tufted capuchin, expanding its range east to Peru and Ecuador and south to Bolivia.

<span class="mw-page-title-main">Black howler</span> Species of New World monkey

The black howler or black-and-gold howler, is among the largest New World monkeys and a member of the Alouatta genus. The black howler is distributed in areas of South America such as Paraguay, southern Brazil, eastern Bolivia, northern Argentina, and Uruguay. This species is sexually dimorphic, with adult males having entirely black fur and adult females and babies of both sexes having an overall golden colouring; which emphasizes black-and-gold in the name. The IUCN Red List has classed the black howler as Near Threatened as a result of a recent population reduction due to a variety of human-caused factors.

<span class="mw-page-title-main">White-eared titi monkey</span> Species of New World monkey

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<span class="mw-page-title-main">Angola colobus</span> Species of Old World monkey

The Angola colobus, Angolan black-and-white colobus, or Angolan colobus is a primate species of Old World monkey belonging to the genus Colobus.

<span class="mw-page-title-main">Wolf's mona monkey</span> Species of Old World monkey

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<span class="mw-page-title-main">Black colobus</span> Species of Old World monkey

The black colobus, or satanic black colobus, is a species of Old World monkey belonging to the genus Colobus. The species is found in a small area of western central Africa. Black colobuses are large, completely covered with black fur, and like all other Colobus monkeys, do not have a thumb. The species has faced large declines in population due to habitat destruction and hunting by humans, and was consequently listed as Vulnerable on the IUCN Red List in 1994.

<span class="mw-page-title-main">Ursine colobus</span> Species of Old World monkey

The ursine colobus, also known as the white-thighed colobus, Geoffroy's black-and-white colobus, or the white-thighed black-and-white colobus, is a West African species of primate in the family Cercopithecidae.

<span class="mw-page-title-main">Pennant's colobus</span> Species of Old World monkey

Pennant's colobus or Pennant's red colobus is a species of tree-dwelling primate in the family Cercopithecidae. It is endemic to tropical Central Africa. Three subspecies have traditionally been recognised but its distribution is peculiarly disjunct and has been considered a biogeographical puzzle, with one population on the island of Bioko, a second in the Niger River Delta in southern Nigeria, and a third in east-central Republic of Congo. It is found in rainforests and marshy forests. It is threatened by habitat loss and hunting for bushmeat.

<span class="mw-page-title-main">Tana River red colobus</span> Species of Old World monkey

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<span class="mw-page-title-main">Olive colobus</span> Species of Old World monkey

The olive colobus monkey, also known as the green colobus or Van Beneden's colobus, is a species of primate in the family Cercopithecidae. Its English name refers to its dull olive upperparts. It is the smallest example of all colobine monkeys and is rarely observed in its natural habitat because of its cryptic coloration and secretive nature. It is found in the rain forests of West Africa, ranging from southern Sierra Leone to Nigeria. The IUCN Red List classifies the olive colobus as vulnerable, with the cause of its decline attributed to habitat loss and hunting. Though much of the land within the range of the olive colobus has been affected by human activities, it retains its ability to thrive in small degraded forest fragments.

<span class="mw-page-title-main">Ugandan red colobus</span> Species of Old World monkey

The Ugandan red colobus or ashy red colobus is an endangered species of red colobus monkey, recognised as a distinct species since 2001. There is disagreement however over taxonomy with many considering the Ugandan red colobus to be a subspecies. The Ugandan red colobus is an Old World monkey which is found in five different locations across Uganda and Tanzania.

<span class="mw-page-title-main">Ruwenzori colobus</span>

The Ruwenzori colobus, also known as Ruwenzori black-and-white colobus, is a subspecies of the Angola colobus. This primate is distributed from the Afromontane forests of the Ruwenzori Mountains across the mountains in Burundi and Rwanda to the northern shore of Lake Tanganyika.

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Sources