Olive Baboon[1]

Scientific classification

Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Primates Family: Cercopithecidae Genus: Papio Species: P. anubis

Binomial name

Papio anubis (Lesson, 1827)

The Olive Baboon (Papio anubis), also called the Anubis Baboon, is a member of the family Cercopithecidae (Old World monkeys). The species is the most widely spread of all baboons: it is found in 25 countries throughout Africa, extending south from Mali to Ethiopia and to Tanzania. Isolated populations are also in some mountainous regions of the Sahara. It inhabits savannahs, steppes and forest areas.

Physical characteristics

The Olive Baboon is named for its coat, which is, at a distance, a shade of green-grey.^[3] (Its alternate name comes from the Egyptian god Anubis, which was often represented with dog head and resembled the dog-like muzzle of the baboon.) At closer range, its coat is multi-colored, due to rings of yellow-brown and black on the hairs.^[4] The hair on the baboon's face, however, is finer and ranges from dark grey to black.^[3] This coloration is shared by both sexes, although males have a mane of longer hairs that tapers down to ordinary length along the back.^[4] Besides the mane, the male Olive Baboon differs from the female in terms of size and weight.^[4] Males are, on average, 70 cm tall and weigh 24 kg; females measure 60 cm and 14.7 kg.^[4]

Like other baboons, the Olive Baboon, does not have a flat face, but a long, pointed dog-like muzzle.^[4] In fact, along with their muzzle, the baboons’ tail (38 – 58 cm) and four legged gait can make them seem very canine.^[3] The tail almost looks as if someone broke it, because the tail is held upright over the rump for the first quarter, after which it drops sharply.^[3] The bare patch of a baboon's rump, famously seen in cartoons and movies, is a good deal smaller in the Olive Baboon.^[4] The Olive Baboon, like most cercopithecines, has a cheek pouch with which to store food.^[3]

Range & Habitat

The Olive Baboon inhabits a strip of 25 equatorial African countries, very nearly ranging from the east to west coast of the continent.^[3] The exact boundaries of this strip are a little blurry, as the species' territory overlaps with that of other baboon species.^[3] In many places, this has resulted in cross-breeding between species.^[3] For example, there has been considerable hybridization between the Olive Baboon and the Hamadryas Baboon in Ethiopia.^[3] Cross-breeding with the Yellow Baboon and the Guinea Baboon has also been observed.^[4] Although this has been noted, the hybrids have not been heavily studied yet.^[3]

Throughout this wide range, the Olive Baboon can be found in a number of different habitats.^[4] It is usually classified as savanna-dwelling, living in the wide plains of the grasslands.^[4] The grasslands, especially those near open woodland, do make up a large part of its habitat, but the baboon also inhabits jungles and deserts.^[4] Uganda and the Democratic Republic of the Congo, for instance, both support Olive Baboon populations in dense tropical forests.^[3]

Food habits

One major reason for its widespread success is that the Olive Baboon is not bound to a specific food source.^[3] It is omnivores, and can find nutrition in almost any environment because of its ability to adapt to different foraging tactics.^[3] The Olive Baboon in grassland then will go about finding food differently than those in a forest.^[3] It is also worth noting that the baboon will forage on all levels of an environment: above and beneath the ground and in the canopy of forests.^[5] Most animals will only look for food at one level; an arboreal species for instance, such as a lemur, will not look for food on the ground. The Olive Baboon will search as wide an area as it can, and eat virtually everything it finds.^[5]

Virtually everything includes a large variety of plants, and invertebrates through small vertebrates.^[6] The Olive Baboon will eat leaves, grass, roots, bark, flowers, fruit, lichens, tubers, seeds, mushrooms, corms and rhizomes.^[6] Corms and rhizomes are especially important in times of drought, because grass loses a great deal of its nutritional value.^[6] In dry, arid regions, such as the northeastern deserts, small invertebrates like insects, spiders, and scorpions fill out its diet.^[6]

The Olive Baboon will also hunt prey, from small rodents and rabbits to other mammals and other primates.^[3] Its limit is usually small deer, such as Thompson's Gazelle, which accounts for 33% of its food from hunting.^[3] Hunting is usually a group activity, with both males and females participating.^[3] Interestingly, there is evidence that this systematic predation was developed recently. ^[7] In a field study, such behavior was observed as starting with the males of one troop and spreading through all ages and sexes.^[7]

Behavior and mating

The Olive Baboon lives in groups of size 15-150 made up of a few males, many females, and their young.^[3] There is a complex social hierarchy similar to that found in other primates, such as gorillas and chimpanzees.^[4] Each baboon has a social ranking somewhere in the group, depending on its dominance.^[3] Female dominance is hereditary, with daughters having nearly the same rank as their mothers.^[3] Males, however, establish their dominance more forcefully.^[3] They will try to bully other males and cow them into obedience.^[3] Fights are not uncommon between males, and the loser will submit afterwards.^[3]

Higher dominance means an easier time mating and earlier access to food, so there is naturally a great deal of fighting over rank, with younger males constantly trying to rise in position.^[3] Because females stay with their group their entire life, and males emigrate to others, there is often a new male challenging an older one for dominance.^[3] Frequently, when older baboons drop in the social hierarchy, they will move to another tribe.^[4] It has been observed that the younger males who pushed them down will often bully and harass the older.^[4]

Females are sexually mature at 7-8 years, and males at 7-10 years.^[4] The beginning of their ovulation is a signal to the males that she is ready. During ovulation, the skin of the female's anogenital area swells and turns a bright red/pink.^[8] The swelling makes it difficult to move and increases the female's chance of infection or parasite.^[8] It also attracts males, who will compete with each other to see who can mate with the female,^[8] with more dominant males having a better chance of mating, simply because they can keep other males away from the ovulating female.^[3]

References

 

1. ^ Groves, Colin (16 November 2005). Wilson, D. E., and Reeder, D. M. (eds): Mammal Species of the World, 3rd edition, Johns Hopkins University Press, 166. ISBN 0-801-88221-4. 
2. ^ Butynski, T. & Members of the Primate Specialist Group (2000). Papio anubis. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006.
3. ^ ^{a b c d e f g h i j k l m n o p q r s t u v w x y z} Cawthon Lang, KA (2006-04-18). Primate Factsheets: Olive baboon (Papio anubis) Taxonomy, Morphology, & Ecology. Retrieved on 2007-01-27.
4. ^ ^{a b c d e f g h i j k l m n} Shefferly, N. (2004). Papio anubis. [http://animaldiversity.ummz.umich.edu Animal Diversity Web. Retrieved on 2007-01-27.
5. ^ ^{a b} Olejar, Marian Jr.. Olive Baboon. Olejar's Encyclopedia of Animals. Retrieved on 2007-01-27.
6. ^ ^{a b c d} Skelton, S.. Savanna Baboon (Papio cynocephalusd). Retrieved on 2007-01-29.
7. ^ ^{a b} Strum, S C. (1975). "Primate Predation: Interim Report on the Development of a Tradition in a Troop of Olive Baboons". Science 187: 4178.
8. ^ ^{a b c} Motluk, Alison (2001). "Big Bottom". New Scientist 19 (07).