Papio ursinus (Kerr, 1792)

Scientific Naming and Size Status

The chacma baboon, scientifically named Papio ursinus (Kerr, 1792), is possibly the longest extant monkey species.

Body and Tail Length

Adult body length ranges from 50 to 115 cm (20 to 45 in), while tail length measures 45 to 84 cm (18 to 33 in).

Sexual Dimorphism Overview

It is also one of the heaviest monkey species, displaying strong sexual dimorphism: females are considerably smaller than males.

Adult Weight Ranges

Adult males weigh between 21 and 45 kg (46 to 99 lb), with an average weight of 31.8 kg (70 lb); adult females weigh between 12 and 25 kg (26 to 55 lb), with an average weight of 15.4 kg (34 lb).

Size Dimorphism Extent

In some cases, adult males can be roughly twice as long and three times as heavy as adult females.

Size Comparison to Olive Baboon

The chacma baboon is similar in size to the olive baboon, with a slightly higher average mean body mass.

Size Comparison to Mandrill

It has a similar weight to the more compact mandrill: male mandrills average about 1 kg (2.2 lb) heavier than male chacma baboons, while female mandrills are 3 kg (6.6 lb) lighter than female chacma baboons.

Largest Monkey Distinction

Though mandrills are typically recognized as the largest living monkeys, when measured by total length and average (not maximum) body mass across both sexes, the chacma baboon is considered the largest extant monkey.

General Fur Coloration

The chacma baboon’s fur is generally dark brown to gray, with a patch of coarse hair on the nape of its neck.

Male Mane Absence

Unlike males of northern baboon species (Guinea, hamadryas, and olive baboons), male chacma baboons do not have a mane.

Distinctive Facial Feature

The species’ most distinctive feature is its long, downward-sloping face.

Male Canine Tooth Length

When male chacma baboons leave their natal troop, their canine teeth have an average length of 3.86 ± 0.30 cm (1.52 ± 0.12 in).

Canine Tooth Wear

This is the maximum tooth length they reach, as teeth become worn or broken over time.

Subspecies Basis

The species has three subspecies, distinguished by differences in size and color.

Cape Chacma Traits

The Cape chacma is large and heavy, with dark brown fur and black feet.

Gray-footed Chacma Traits

The gray-footed chacma is slightly smaller than the Cape chacma, with lighter fur, a slighter build, and gray feet.

Ruacana Chacma Traits

The Ruacana chacma is generally a smaller, less darkly colored version of the Cape chacma.

Habitat Types

Chacma baboons live across a wide variety of habitats, including woodland, savanna, steppes, and subdesert, ranging from the grassy alpine slopes of the Drakensberg to the Kalahari Desert.

Sleeping Site Characteristics

At night, they sleep on top of steep hills, high cliffs, rocks, or in large trees, to stay away from nocturnal predators.

Arid Range Limitation

During the day, access to water can limit the species’ range in arid regions.

Overall Geographic Range

The chacma baboon is found across southern Africa, ranging from South Africa northward to Angola, Zambia, and Mozambique.

Subspecies Distribution

Its subspecies are distributed across separate parts of this range: the Cape chacma lives in southern South Africa; the gray-footed chacma occurs from northern South Africa, through Botswana’s Okavango Delta, Zimbabwe, Mozambique (south of the Zambezi), to southwest Zambia; and the Ruacana chacma inhabits northern Namibia and southern Angola.