About Great Apes


Primates

Primates are mammals which share the following characteristics:

  • Hair instead of fur
  • Finger nails instead of claws
  • Opposable thumbs
  • Higher brain to body size ratio– high level of intelligence
  • Prehensility– ability to grasp with fingers and/or toes
  • Padded digits with fingerprints
  • Binocular vision– both eyes focus on one object (depth perception)
  • Reduced olfactory sense and dependent on vision more than smell

Differences Between Monkeys and Apes

Although there are a number of differences between monkeys and apes (apes have longer lifespan, larger body size, larger brain to body size ratio, and higher intelligence)… the main difference is that monkeys have tails…. apes do not have tails.

Species of Apes

There are two types of Lesser Apes:
  • Gibbons (SE Asia)
  • Siamangs (SE Asia)
There are four types of Great Apes:


Chimpanzees

Chimpanzees are great apes that live in the tropical rain forests of Africa from Sudan and Tanzania in the East to Senegal and Angola in the West. Zaire has the largest population, although chimpanzees have become extinct in some areas.

They grow to reach heights of 3-5 feet, and weigh up to 120 - 200 pounds. They are predominantly black, sometimes with gray on their back after 20 years of age.


Distinctive Habits and Characteristics

  • Chimpanzees are the most social of all the apes living in communities of between 15 and 120 individuals.
  • Their communities are often split into a number of subgroups with a male as the leader of the group.
  • Males seldom leave the community where they were born.
  • Females often migrate to a new community during an adolescent estrus period.
  • Chimpanzees travel mostly on the ground (terrestrial) by knuckle walking.
  • Chimpanzees groom each other daily, and this activity has an important social function of calming and comforting individuals and solidifying bonds with each other.
  • Mothers often travel alone with their offspring.
  • They construct nests at night in which to sleep.
  • Chimpanzee males in the wild cooperative hunt for meat.
  • Their diet is mainly fruits with regular amounts of insects, as well as birds and small mammals.
  • Chimpanzees use tools to gain access to food, such as fishing for termites with sticks fashioned for the job and cracking open nuts with anvil-like rocks.
  • Females in estrus have a prominent swelling of the pink perineal skin, lasting two to three weeks and occurring every four to six weeks.
  • Females give birth every 4 to 5 years and their gestation period is 8 to 9 months.
  • Chimpanzees have a long mother-infant dependency period where infants will nurse on their mothers for 5 years and stay with their mothers several more years learning to care for younger siblings.
  • The life span for chimpanzees is 40 to 50 years in the wild and over 50 to 60 years in captivity.

There are four distinct populations of chipanzees in Africa:

  • Pan troglodytes troglodytes – central Africa
  • Pan troglodytes vellerosus - Cameroon and Nigeria
  • Pan troglodytes verus - western Africa
  • Pan troglodytes schweinfurthii - eastern Africa

Life Stages

Infant:Birth to 5 years (nursed and carried by mother)
Juvenile:5 to 8 years (still with mother but independent of her for transport and milk)
Early Adolescence: Female - 8 to 10 years                 Male - 8 to 12 years
Late Adolescence:Female - 11 to 14 years               Male - 13 to 15 years
Maturity: 16 to 33 years
Old Age: 33 years to death


Endangered Status

The current chimpanzee population is estimated between 80,000 to 120,000. The number one threat is the bush meat trade in which 6,000 chimpanzees per year are killed and eaten by humans. Chimpanzees are currently threatened to extinction by habitat destruction for logging and mining, as well as poaching for the pet trade. When poached, mothers are killed, and if a baby survives the fall of the mother from the tree, the baby is taken by poachers.



Orangutans

Orangutans are found in the tropical rain forests of only two islands in the world – Sumatra (in Indonesia) and Borneo (in Malaysia and Indonesia).

They are the largest arboreal (tree dwelling) animal in the world, reaching heights of 4-5 feet and weights of 125-235 pounds or more. Orangutans are reddish-brown in color and some males grow white or yellow beards. Also characteristic are their bare faces with round eyes and small ears; their long, shaggy hair; long arms; and curled fingers and feet.

Males are much larger than females and develop large pads on cheeks called “flanges” and large throat pouches at the age 15 to 20. They spend most of their time in trees and subsist mainly on fruit, leaves, flowers, buds, bark and insects.


Distinctive Habits and Characteristics

  • Adult males lead mostly solitary lives (except when consorting with females.
  • Females associate with their infant and juvenile offspring and occasionally an adult sister or mother for short periods of time.
  • Males communicate by the "long call" for territorial and courting purposes.
  • Both sexes are arboreal, spending most of their time in trees, building nests at night, swinging through the trees, and eating in the trees.
  • The lighter an orangutan is, the more active; as they grow older and heavier, they become slower and more cautious, testing each branch before putting their full weight on it.
  • They rarely descend from treetops to ground; when they do, they usually walk on all fours (quadrupedal).
  • Orangutans’ arms are stronger and longer than their legs (1½ times longer).
  • Their reach from fingertip to fingertip can be as long as 8 feet.
  • They pucker up their lips to feel the texture of a piece of fruit or food before they bite into it. .
  • While they are primarily herbivorous and love jungle fruits like durian, jackfruit, and lychee nuts….orangutans have been observed in the wild catching and eating a small animal called a slow loris.
  • Females only give birth every 7 to 9 years, and their gestation period is about nine months (227 to 275 days).
  • Infants nurse on their mothers for 4 to 5 years and stay in their mother’s nest for about 7 to 8 years.
  • Females raise their infants alone.
  • Orangutans can live 40 years in the wild and over 50 years in captivity.


There are four sub-species of orangutan

In Sumatra:      
  • pongo abelli
  • In Borneo:
  • pongo pygmaeus pygmaeus
  • pongo pygmaeus wurmbii
  • pongo pygmaeus morio

  • Life Stages

    Infant:Birth to 4 years (carried by mother)
    Juvenile:4 to 8 years (still with mother)
    Early Adolescence: Female - 8 to 15 years                 Male - 8 to 13 years
    Sub-adult:13 to 18 years (males only)
    Adult: Female - 15+ years                       Male - 18+ years


    Endangered Status

    The current population of orangutans is less than 60,000 individuals (about 53,000 in Borneo and roughly 6,000 in Sumatra). They are gravely threatened to extinction due to habitat destruction (logging, farming, gold mining) and poaching for pet trade. When poached, mothers are killed, and if baby survives fall of mother from tree, the baby is taken by poachers.

    One of the biggest threats today to orangutans is palm oil. Virgin forests where orangutans live and find all their food are cut down bare in order to plant the cash crop for palm oil. This oil is widely used in foods and consumers should be aware of ingredients in cookies, ice cream and other foods… and not buy products that use palm oil. More threatening now is the use of palm oil in bio fuels. Nearly 5000 orangutans a year have been killed or died over the past few years as palm oil plantations take up their habitat.