Ask Difference

Old World Monkeys vs. New World Monkeys — What's the Difference?

By Maham Liaqat & Fiza Rafique — Published on March 3, 2024
Old World Monkeys, found in Africa and Asia, have narrow, downward noses, unlike New World Monkeys from the Americas with wider, side-facing nostrils. Old World types also lack prehensile tails.
Old World Monkeys vs. New World Monkeys — What's the Difference?

Difference Between Old World Monkeys and New World Monkeys


Key Differences

Old World Monkeys inhabit parts of Africa and Asia, adapting to diverse environments from rainforests to mountains. They're known for their more terrestrial lifestyles compared to the New World Monkeys, which are found in Central and South America, often living in trees.
The facial structure of Old World Monkeys includes narrow nostrils that face downward, a feature that differs markedly from New World Monkeys, whose nostrils are wide and face sideways. This distinction is one of the easiest ways to tell them apart.
Old World Monkeys generally have non-prehensile tails, meaning they cannot use their tails to grasp or hold objects. In contrast, many New World Monkeys boast prehensile tails, an adaptation for arboreal living, allowing them to navigate the forest canopy more effectively.
Regarding dentition, Old World Monkeys have bilophodont molars (two ridges), which is different from the New World Monkeys' dental formula, which often includes molars with three ridges. This reflects their different diets and foraging behaviors.
Old World Monkeys tend to be larger and more varied in size compared to New World Monkeys. The size and physical adaptations of Old World Monkeys equip them for a range of habitats, including ground-dwelling, while New World Monkeys are generally smaller and more specialized for life in the trees.

Comparison Chart


Africa and Asia

Nose Structure

Narrow, downward-facing nostrils
Wide, side-facing nostrils


Many species have prehensile tails


Bilophodont (two ridges)
Often trilophodont (three ridges)

Size and Physical Adaptations

Generally larger, more varied
Generally smaller, more arboreal

Compare with Definitions

Old World Monkeys

Have non-prehensile tails, unlike their New World counterparts.
Old World Monkeys use their tails for balance, not for grasping.

New World Monkeys

Smaller and more specialized for tree-dwelling than Old World Monkeys.
Marmosets, tiny New World Monkeys, are experts at life in the treetops.

Old World Monkeys

Lack the color vision diversity found in many New World Monkeys.
Despite their size, Old World Monkeys typically have less color vision variation.

New World Monkeys

Possess a wider range of color vision, aiding in food selection.
The howler monkey's color vision is crucial for identifying ripe fruits.

Old World Monkeys

Terrestrial and arboreal primates from Africa and Asia with downward-facing nostrils.
The baboon, an Old World Monkey, is known for its terrestrial lifestyle.

New World Monkeys

Arboreal primates from the Americas with side-facing nostrils.
The spider monkey, a New World Monkey, uses its prehensile tail to swing between trees.

Old World Monkeys

Show greater size and habitat diversity than New World Monkeys.
The mandrill, one of the largest Old World Monkeys, inhabits various African forests.

New World Monkeys

Many species have prehensile tails for arboreal navigation.
Capuchins use their tails as a fifth limb when moving through the canopy.

Old World Monkeys

Exhibit bilophodont molar patterns, suited to their diet.
The macaque's bilophodont molars are ideal for grinding foliage.

New World Monkeys

Often feature trilophodont molars, reflecting their diet.
New World Monkeys, like the tamarin, have molars adapted for a varied diet.

Common Curiosities

What is the main habitat difference between Old World and New World Monkeys?

Old World Monkeys are native to Africa and Asia, while New World Monkeys live in the Americas.

Can Old World Monkeys use their tails to grasp objects?

No, Old World Monkeys have non-prehensile tails and cannot grasp objects with them.

Do both Old and New World Monkeys have the same type of molars?

No, Old World Monkeys have bilophodont molars, while New World Monkeys often have trilophodont molars.

Are New World Monkeys larger than Old World Monkeys?

Generally, no; Old World Monkeys tend to be larger and more varied in size.

Do all New World Monkeys have prehensile tails?

Not all, but many species do, which aids in their arboreal lifestyle.

How do the diets of these two monkey groups compare?

Their diets can vary widely, but dental differences like bilophodont versus trilophodont molars reflect adaptations to different dietary needs.

What is a distinctive feature of New World Monkeys' noses?

New World Monkeys have wide, side-facing nostrils.

Which group shows more diversity in habitat and size?

Old World Monkeys exhibit greater diversity in habitat and size.

Are there any Old World Monkeys in the Americas?

No, Old World Monkeys are native to Africa and Asia only.

Do Old World Monkeys have any arboreal species?

Yes, while many are terrestrial, there are also arboreal species among Old World Monkeys.

Is there a difference in the arboreal adaptations between these two groups?

Yes, many New World Monkeys have prehensile tails for better arboreal movement, unlike Old World Monkeys.

Are the social structures of Old World and New World Monkeys similar?

Social structures can vary widely within both groups, but both include species with complex social systems.

Can New World Monkeys see more colors than Old World Monkeys?

Many New World Monkeys have a wider range of color vision, which is beneficial for their diet.

Why do New World Monkeys have prehensile tails?

Prehensile tails allow New World Monkeys to navigate and stabilize themselves in the forest canopy more effectively.

What is the significance of the nostril direction in these monkeys?

The nostril direction is a key physical trait that helps distinguish between Old and New World Monkeys.

Share Your Discovery

Share via Social Media
Embed This Content
Embed Code
Share Directly via Messenger

Author Spotlight

Written by
Maham Liaqat
Co-written by
Fiza Rafique
Fiza Rafique is a skilled content writer at, where she meticulously refines and enhances written pieces. Drawing from her vast editorial expertise, Fiza ensures clarity, accuracy, and precision in every article. Passionate about language, she continually seeks to elevate the quality of content for readers worldwide.

Popular Comparisons

Trending Comparisons

New Comparisons

Trending Terms