Platyrrhines vs. Catarrhines Overview

Questions and Answers

What are the traits that distinguish platyrrhines from catarrhines?

Platyrrhines feature a 2:1:3:3 dental formula, flat nose nostrils outward, prehensile tail (not all platyrrhines have a prehensile tail but if you see a prehensile tail, you know that it is a platyrrhine), exclusively arboreal.

When do platyrrhines first appear in the fossil record? From where do they likely originate? How did they most likely get to the New World?

Oligocene (26 mya) deposits in Bolivia; likely originated in Africa; most likely by rafting across the south Atlantic from Africa to South America.

To what family does the white-faced saki belong? What type of diet does it have, and what adaptation does it have for this food resource?

Pithecia; It is granivorous and has large incisors and flat molars. The adaptation is that their incisors jut forward in order to crack seeds.

To what family do capuchins belong? What behaviors are these monkeys known for?

Cebinae; Capuchins are known for being highly intelligent and commonly living in human environments. They are also known to use tools (hammerstones for cracking nuts, clam opening). Signup and view all the answers

To what family do owl monkeys belong? What is unique about owl monkeys?

Aotidae; They are the only nocturnal New World monkey; they have secondarily derived large eyes and no tapetum lucidum. Signup and view all the answers

To what family do marmosets and tamarins belong? What anatomical adaptations and aspects of social behavior make these monkeys unique?

Callitrichidae; They have re-evolved some primitive traits, such as claws on some digits and a small body size. They also give birth to litters (twins), allowing the father to provide an unusual amount of parental care. Signup and view all the answers

To what family do spider monkeys belong? How have they converged behaviorally on apes, and how is this reflected in their skeletons?

Atelidae; Spider monkeys are suspensory in a way that is similar to apes and have converged in their thorax shape/rib cage, looking more ape-like than monkey-like. Signup and view all the answers

To what family do howler monkeys belong? What is unique about these monkeys compared to other primates?

Atelidae; They are the loudest living land mammal (due to a specialized hyoid bone) and the only folivorous New World monkey. Signup and view all the answers

What shared derived traits distinguish catarrhines from other primates?

Catarrhines are known as raised rounded-nosed primates, have a 2:1:2:3 dental formula (bilophodont), downward facing nostrils, and a temporal tube. Signup and view all the answers

What family represents Old World monkeys? What shared derived traits distinguish this family from other primates?

Cercopithecidae; shared derived traits include ischial callosities (butt pads) and bilophodont teeth. Signup and view all the answers

Where are Old World monkeys found, and what is outstanding about their distribution compared to other living non-human primates?

Old World monkeys are found in Asia and Africa; they have the widest distribution and occupy very different environments. Signup and view all the answers

When do Old World monkeys first appear in the fossil record, and what is an example of an early family/member of this group?

They first appear in the fossil record around the early Miocene, with an example being Victoriapithecus, which lived in Africa and Eurasia in the mid-Miocene. Signup and view all the answers

What are the two major groups of living Old World monkeys? What distinguishes them from one another?

Colobines (leaf-eating monkeys) and Cercopithecines (cheek pouch monkeys). Signup and view all the answers

To which Old World monkey group does the macaque belong? What is extraordinary about macaques regarding their geographic distribution?

Cercopithecines; they are mostly found in Asia, but can also be found in Africa, having the widest distribution of any genus. Signup and view all the answers

To which Old World monkey group does the mandrill belong? What is a distinguishing feature of the mandrill when compared to other primates?

Cercopithecine; they are the brightest colored primates, with males being two times the size of females, indicating high levels of male-to-male competition shaped by intersexual selection. Signup and view all the answers

To which Old World monkey group does the gelada baboon belong? Where are modern gelada baboons found?

Cercopithecine; found in the highlands of Ethiopia. Signup and view all the answers

What is unique about the leaf-eating monkey infant/neonatal coat pattern?

The leaf-eating monkey infants are always colored differently than older monkeys and develop the adult coloration once they reach a certain age. Signup and view all the answers

To which Old World monkey group does the proboscis monkey belong? What distinguishing feature does the proboscis monkey have?

Colobine; they have a very large nose that is an intersexually selected trait that helps them radiate sound. Signup and view all the answers

To which Old World monkey group do the colobus monkeys belong? Where are colobus monkeys found?

Colobine; found in Africa. Signup and view all the answers

Given the lack of fossils for the living colobus monkeys, how do we know when they diverged back in time?

Using a molecular clock to look at the rate mutations occurred and predict how long ago those mutations happened. Signup and view all the answers

Study Notes

Platyrrhines vs. Catarrhines

Platyrrhines have a 2:1:3:3 dental formula, outward-facing nostrils, and often possess prehensile tails, primarily living arboreally.
Catarrhines possess a 2:1:2:3 dental formula, with downward-facing nostrils and a temporal tube.

Origin and Early Fossil Record

Platyrrhines first appeared in the Oligocene epoch, approximately 26 million years ago, in Bolivia, with fossils resembling modern forms found in mid-late Miocene deposits in Patagonia.
They likely originated in Africa and migrated to South America via rafting across the South Atlantic Ocean.

White-faced Saki

Belongs to the family Pithecia.
Granivorous diet supported by large incisors and flat molars, with incisors adapting to crack seeds.

Capuchins

Part of the Cebinae family.
Known for high intelligence, tool use (e.g., hammerstones for cracking nuts), and living in close proximity to humans, aided by dexterous hands and large brains.

Owl Monkeys

Members of the Aotidae family.
Unique as the only nocturnal New World monkeys, featuring large eyes and lacking a tapetum lucidum.

Marmosets and Tamarins

Belong to the Callitrichidae family.
They exhibit primitive traits such as claws on digits and small body sizes, and often give birth to twins, leading to significant paternal care.

Spider Monkeys

Part of the Atelidae family.
Behaviorally similar to apes, with a suspensory locomotion reflected in their ape-like thorax shape and rib cage.

Howler Monkeys

Also belong to Atelidae.
Known as the loudest land mammal due to specialized hyoid bones; they are the only folivorous New World monkeys.

Catarrhine Characteristics

Catarrhines have raised, rounded noses and a bilophodont dental pattern, with shared derived traits including the temporal tube.

Old World Monkeys

Represented by the family Cercopithecidae, characterized by ischial callosities (butt pads) and bilophodont molars.

Distribution of Old World Monkeys

Found in diverse environments across Asia and Africa, exhibiting the widest distribution among non-human primates, including habitats like snow (Japanese macaques) and high altitudes (baboons).

Fossil Record of Old World Monkeys

First appearing around the early Miocene, with modern families like Victoriapithecus found by the mid Miocene, inhabiting Africa and Eurasia.

Divisions of Old World Monkeys

Divided into Colobines (leaf-eating monkeys) and Cercopithecines (cheek pouch monkeys), distinguished by dietary preferences.

Macaques

Classified under Cercopithecines with an extraordinary geographic distribution, primarily in Asia but also found in Africa, holding the widest range of any genus.

Mandrills

Part of the Cercopithecine family; they are renowned for being the most brightly colored primates, with males typically twice the size of females, showcasing intersexual selection.

Gelada Baboons

Belong to the Cercopithecine group, found in Ethiopia's highlands. They have a unique grass-based diet and large social groups, engaging in vocal grooming.

Leaf-eating Monkey Infants

Have distinct coat patterns that differ from adults and transition to adult coloration as they mature.

Proboscis Monkey

A Colobine species recognized for its large nose, an intersexually selected trait aiding in sound amplification.

Colobus Monkeys

Found in Africa; divergence from ancestors is estimated using molecular clocks, assessing mutation rates to determine evolutionary timelines.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers the distinguishing traits of platyrrhines and catarrhines, including their dental formula and evolutionary history. Test your knowledge on the origins and characteristics of these primate subfamilies.