New World monkeys, also known as Platyrrhini, are found in the rainforests of Central and South America. There are four main differences between New World and Old World monkeys: New World monkeys have flared nostrils, a different dental pattern with three premolars instead of two, prehensile tails used as a fifth limb, and they lack the butt pad that Old World monkeys have. New World monkeys also tend to be smaller in size than Old World monkeys.

1. Platyrrhini
New World Monkeys

2. Geography
• Located in rain forests of Central and South America

3. Why Different?
• There are several major
differences between Old
World and New World
monkeys but 4 in
particular.
• Nostrils – New World
Monkeys have nostrils
that flare out. Platyrrhini
means “flat nose”.
Where Old World
monkeys flare down.

4. Why Different
• New World monkeys
have a different
dental pattern than
Old World monkeys.
• They pattern 2-1-3-3.
Meaning they have 3
premolars (bicuspids)
instead of 2.

5. Why Different?
• New World monkeys
have Prehensile Tails.
They act as a 5th arm.
• They use it as an
adaptation of strictly
arboreal living.

6. Why Different?
• New World monkeys Baboon (Old World Monkey) Butt Pad
lack the butt pad that
Old World Monkeys
have.
• Due to lack of
terrestrial living and
New World monkey
are primarily
monogamous, no need
of butt pad for
attracting mates.

7. Size
• New World monkeys tend to be smaller than Old World
monkeys. They range from a few ounces (Pygmy Marmoset)
to around 30 pounds (Howler monkeys).

8. Ecology
• While the numbers of New World monkeys are stable. They
are losing habitat and some species are endangered and
threatened.
• It is our responsibility to protect and save the habitats and
species that need them to survive, not only for the monkeys
but also for all species that call the rain forest their home.