Week 4

Lemurs are found on the island of Madagascar and the Comoro Islands which are located about 250 miles off the Southeast coast of Africa in the Indian Ocean.  The climate of this area ranges from tropical to arid. Lemurs live in all areas of these islands and adapt to their environment but you can find more lemurs in the forests as more food is available.  They live in trees and eat a variety of food for survival.  They mostly eat nuts and fruit but they also eat flowers, sap, tree bark and flowers. Lemurs spend much of their time in the trees but do spend time on the ground as well. 

The dentition pattern of Lemurs is 2-1-3-3 (incisors, canine, premolars, molars). Their incisors and canines are procumbent (face forward) which provides a tool for grooming or feeding such as removing large seeds from fruits.  Their teeth can also cut through bark which enables them to eat the sap.  Their teeth have adapted to the current state so that they can crush seeds and cut through bark.

 

 Spider Monkey

Spider monkeys live in the rain forests of Central and South America and some also live in Mexico.  The spider monkeys look for areas that offer a protective canopy of trees.  Spider Monkeys play a very important role in their habitat as they spread seeds from fruits, plants and flowers which help new vegetation grow.  They forage for their food high in the trees (80 feet – 100 feet high) and they mainly eat fruits but will also eat nuts, bird eggs, spiders, and leaves which they find in the treetops.   

 

The dentition pattern of a spider monkey is 2-1-3-3.  Their sharp teeth help them bite through the hard seeds.

Baboon

Baboons live in Africa and Arabia.  Most of them live in semi-arid environments and tropical forests. They need to live near a water source and seek the protection of tall trees or the cliff faces.  They spend most of their time on the ground but do climb trees to eat and sheep.  They eat fruit, seeds, bark, grass, roots, birds, sheep and even antelopes.

They have very long canine teeth and strong jaws which allow them to be a predator and eat other animals such as sheep.  The dentition pattern of a baboon is 2-1-2-3.

 

 
Gibbon

Gibbons are found in the rain forests of southern Asia. They spend almost all of their lives in the treetops and rarely descend to the ground.  They mostly eat fruit but will eat leaves, insects, tree bark and flowers.  They will sometimes eat birds, bird eggs, tree frogs and insects.

The dentition pattern of a gibbon is 2-1-2-3. They large canine teeth help them rip bark from the trees.

 

Chimpanzee

Chimpanzees live mostly in rain forests but some live in wet savannas of Uganda and Tanzania. Chimpanzees spend their time in trees and on land. They sleep in trees and also scavenge for food in the trees.  The diet of chimpanzees consists of fruit, seeds, insects, and eggs and they will kill and eat birds and even antelope.    

The dentition pattern of a chimpanzee is 2-1-2-3.  Chimpanzees have 32 adult teeth which are the same number as humans.  The upper jaw of chimps is u-shaped.  Their canine teeth are large and pointed.  Chimpanzees don’t need the large canine teeth to eat fruit and leaves but these large teeth could also be used as a threat against enemies.

 

Summary:

Lemurs and spider monkeys share the same pattern of 2-1-3-3.  They have sharp canine teeth due to their diet of mostly bugs.  They are arboreal and over the course of evolution these primates have adapted their diet.

 

Baboons, gibbons, and chimpanzees share the pattern of 2-1-2-3. They eat a variety food including small animals so their large canines allow them to tear their food.  These large canines are very visible and could also be used for intimidation against predators and their prey.  These primates are Omnivore (an animal that eats both plants and animals).  Over the course of evolution this led to the change in their dentition.