Anthropology 1
Introduction to Physical Anthropology


NEW WORLD (AMERICAN) AND OLD WORLD (AFRICA and ASIA) MONKEYS:
A COMPARISON

 

This is a picture of a capuchin, a New World monkey

 

This is a picture of a Douc langur, an Old World monkey

Monkeys flourish in the tropical and subtropical regions of South and Central America, Asia and Africa. Monkeys also are found in regions outside of the tropics in both Africa and Asia (but never in the Americas). Although monkeys everywhere have similar external appearances, a closer look reveals unique and distinctive differences between the American and Old world monkeys.


NOSTRILS

New World monkeys

Flat nosed (or platyrrhine)

Nostrils are far apart and open to the side

Old World monkeys

Downfacing nose (or catarrhine)

Nostrils are closer together and open downward or forward

(Apes and humans share this nasal feature as well.)

 

PREMOLARS and MOLARS

New world monkeys

Three rather than two premolars

Molars are relatively large

The last molar is comparatively small or sometimes absent

Old World monkeys

Two premolars

Premolar in the mandible is SECTORIAL. That is, it's specialized for sharpening the upper canine

Molars have sharply connected cusps

 

EAR REGION

New world monkeys

Tympanic membrane connected to external ear by a bony ring

Old World monkeys

Tympanic membrane connected to external ear by a bony tube (is visible on the outside of the skull)

 

TAILS

New world monkeys

Some species (howlers, spiders) have prehensile tails

Old world monkeys

All have tails ­ but lack prehensility feature

Sitting pads (ischial callosities) around the tail region. These thickly calloused skin areas supports the animals while they sit in trees (or on ground) to feed, rest, or sleep

 

HANDS

New world monkeys

Thumb orientation lies in line with other digits. Opposes the next digit in a scissorslike grip

(Spider monkeys have lost their thumbs)

Fingernails = some species have fingernails on big toe

Old world monkeys

Thumbs are rotated and more opposable, more like ours (Hanuman langurs, baboons)

(Thumbs reduced or absent among colobine monkeys of Africa)

Fingernails and toenails are present on all digits

 

INFANT CARE

New world monkeys

Male involvement common

Old world monkeys

Male involvement rare or absent in most species (gibbons and siamangs are the exception to this non-male involvement)

 

OTHER DIFFERENCES

New world monkeys

Few species have one male ­ multifemale groups like many of the Old World monkey species

Have scent glands ­ rely more on scent to mark territories than Old World species

Old world monkeys

Prominent sexual skin around the anus and vagina in females which swells during estrous cycle

 

HABITATS

New world monkeys

Confined to arboreal habitats

Rely heavily on fruit and less on foliage in comparison to Old World monkeys

Old world monkeys

Tolerate a wider range of habitats, from rainforest through savanna fringe or open savanna to high mtn ranges and semiarid regions ­ even urban environments (remember the hanuman langurs).

Many spend some or most of day on the ground

Some species (leaf-eaters) have specialized digestive tracks for processing low-value food



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