Characters and the Distribution of
Anthropoid Apes
Introduction :
The term anthropoid ape means anthropoid means manlike and ape
means tailless monkey. The living apes and humans are placed in the
superfamily Hominoidea of the order primate. Although it is clear from an
examination of their anatomical features that all the hominoids evolved
from an arboreal ancestor that used its arms to hang underneath
branches, most, but not all hominoids today spend most of their time on
the ground. The superfamily Hominoidea consists of 3 families:
Pongidae, Hylobatidae and Hominidae. The hominids include modern
humans and our immediate ancestors. The pongidae includes the great
apes of both Asia and Africa. The African varieties are Chimpanzee
(genus Pan) and the Gorilla (genus Gorilla). The Asian Pongids are
Orangutan (genus Pongo). The genus pongids are usually distinguished
from the family hylobatidae, the smaller or lesser apes, by a number of
morphological and other features. The hylobatids found in the forest of
south east Asia, are the most arboreal of the apes, they consist of
gibbon (genus Hylobates) and the Siamang( genus Symphalangus).
The relationship between humans and apes can be established with
great advances in molecular anthropology. Molecular anthropology
make it possible today to compare substances that are much closer to
the genetic material, instead of studying only the nonhuman primate’s
external forms and behaviour. Anthropologists are enabling to
understand living primates’ relationship more fully and to reconstruct our
evolutionary history more accurately. More emphasis is given today on
molecular studies for classifying relationships without reference to the
fossil record by comparing gene products.
All higher primates except the Orangutan have one adaption in common,
they live in social groups. All mammals are social; firstly, a higher
primate is born in to social group and plays with its peer throughout its
life. They interact with other members of the group. Their families consist
of varying sizes. 2ndly, generally it includes adult parents and offsprings
or sometimes. Close mother- offspring relationship accompanies the
period of childhood dependency. 3rdly, the period of offspring
dependency, in which the young primate learns by observing and
imitating other animals’ behaviors, picking up appropriate skills and
behaviors in relations to their members of the group. Fourthly, they
communicate between animals by vocal and nonvocal signals. Fifth,
stereotyped, discrete behaviors, learned during maturations, which are
shared by members of the group and ensured its continued existence.
Gibbon Characters and Distribution:
The average height of Gibbon is 3ft. The
average weight is 13 pounds or 5.85 kg.
There is neither reliable size difference
between male and female gibbon nor any
secondary sexual difference that are
easily distinguishable. Most part of the
body is covered with fine woolly hairs,
which contrast to course hairs of great
apes (orangutan, chimpanzee and
gorilla). The coat color shows variation from black to silvery white.
Commonly, the almost naked black face is surrounded by a circle of
white hairs. The brain case of gibbon is relatively large but somewhat
flattened downward with a low forehead elevation. The large oval eye
sockets are surrounded by thickened boney rims, but unlike gorilla they
have no prominent supra-orbital bar/ torus. The face is short, flat but
protrusive. The chin is inhuman. Long spike like canine teeth interlocked
at the corner of the jaws and constitute deadly weapons with which
vicious animals inflict deep, slashing wounds upon the fellows. The arm
swinging motion is just like a pendulum, when the gibbon stops
brachiating, it oscillates before coming to rest. It can cover a distance of
20 feet in and or 2 ½ swings and anticipates the leaf by forceful swing
and hurtles through the air with the trunk bent forward. It is said that
about 90% of the gibbon locomotion is brachiation ( Hooton, 1965). On
the ground they may walk uplift or extended for balancing. The knees
bent forward, the trunk inclined forward and the feet and legs turned
outwards. When it stands erect, its finger tips touch the ground. Gibbon
leg length is 147% and that of arm length is 238% of the trunk length.
(Adolph H. Schultz - Reproduced from
the Hooton). The gibbon hand is very
long with hairless black palm. The
thumb is imperfectly opposable and has
a flatter nail than the claw like, while the
other digits have claw like nails.
Gibbons have small ischial callosities
(thickened skin at the posterior part of
the ischium). There is a deep cleft
between the great toe and the outer
digits. The wide separation gives
increase flexibility to the foot and is of
great advantages in grasping branches.
Family consists of parents and children
but solitary animals of various ages are
seen occasionally. Carpenter has
recorded nine types of vocalization, each of which probably has a
definite communicative function. The cranial capacity is 100 cc. The
dental formula is 2/2, 1/1 ,2/2, 3/3.
Food habit
They depend on fruits (80%), leaves, buds, flowers, birds, eggs, young
birds and insects that provide the necessary protein.
Distribution
Gibbon's habitat consist of tropical forests of south east Asia, including
Java, Sumatra Philippines etc. They are also found in North east India
(Assam) and Myanmar.
Orangutan Characters and Distribution :
They are very bulky and powerful animal
because of the extreme shortness of its
legs. The height is more than 4 feet.
Females are much smaller and lighter
than the males. The weight ranges from
165-200 pounds or 74.25-90 kg in males
and in females the average weight is 81
pounds or 36.45 kg. The body of the
orangutan with exception of face, ears,
palms and soles is sparsely covered with
long reddish brown hairs. The skin is
brownish. The head is enormously large
with protrusive face and jaws. The
forehead is high and rounded. Supraorbital ridges are small. The upper and
the lower lips are very long and stretched
over the bulging jaws. The ear is small.
The adult males have cheek pads which
are absent in other apes. The canine teeth are tusk like and interlocking.
The presence of long sagittal crest running from front to back of the
skull, which provides attachment for tremendous muscles and ligaments
that work the jaw and also that hold up the head. All together 12 pairs of
ribs are present, while gorilla, chimp and gibbon have 13 pairs. Arms are
much longer than legs and the upper part of the body is elevated when
the animal walks resting on the knuckles of the fingers and toes. The
great toe projects inward from the long axis of the foot. On the ground, it
walks on all fours, but can straighten up and walk upright if it desires but
with extreme difficulty. On account of great weight, the movement is slow
and deliberate. At day time, they spend at the top of the tallest trees and
at night they descends to the lower and form nest. These animals are
not very social. Males apparently keep apart from females except in the
mating season. The life span is 40-50 years. They are arboreal animal.
The dental formula is 2/2, 1/1 ,2/2, 3/3.
Distribution
At present, they are found distributed in the islands of Sumatra and
Borneo. But fossil remains of Orangutan suggest that they were
distributed in other parts of the world (Roy, 2003).
Food habit
They live on fruits, leaves shoots. They are very fond of spiny fruits of
Durian.
Chimpanzee Characters and Distribution:
The chimpanzee variety is of three types:
1. Pigmy chimpanzee,
2. Bald headed chimpanzee,
3. Black faced chimpanzee,
4. White chimpanzee.
Most available information pertains to
white faced chimpanzee. The average
height of male chimpanzee ranges
from 5’ to 5’ 7’’, while for female is 4’ to
4’ 3’’. The average weight of male
chimpanzee is 125 kg and the average
weight for female is 100 kg. Therefore,
females are smaller in size and weight
than than males. Body is covered with long
coarse hairs of different colors. Face, hand and
feet are devoid of hairs. The cranial capacity
ranges between 400-500 cc. The head is low
vaulted. Supra orbital ridges are marked and
continuous but not massive forming torus as
those of the gorilla. Nose is flat, depressed in
the middle and inhuman shape at its tip. The
chin is absent. Canine teeth are massive and
projecting but not so large as those of orangutan and gorilla. Ears are
very large which stands out from the head; pale in color and without
lobes. When Chimpanzee stands erect, the finger tip touches above the
knee. Chimpanzee legs are larger than those of orangutan and arms are
shorter than legs. The hands are long and narrow with elongated fingers
but the thumb is small. Foot is also long and narrow, but the great toe is
short and thick and projects inward from the middle of the inner margin
of the foot, being separated from the other toes and also opposable too
other toes. The foot is essentially grasping organ. The lesser toes are
very long and are partially webbed. The heel is poorly developed. The
trunk is thick and the abdomen is rounded. The skin of the hand and
face are pink or nearly white. In case of bold headed, it is black. They
are expert climbers and they can swing from one bough to another with
great agility. They build their nest on the tree but most of the time
spends on the ground. They are terrestrial animal. Chimpanzees are
capable of walking and standing erect for short time and distances. On
the ground, they move quadrupedally and run about on all fours. They
are capable of using tools. By picking up small grasses and twigs they
can prepare a devise and inserted it in the nest of the termites to catch
them. In group, they often make noise by some sort of vocals. The
dental formula is 2/2, 1/1, 2/2, 3/3.
Distribution
Chimpanzees are found distributed through the wide range of tropical
forests of Africa extending from Gambia in the north to Angola in the
south, in the west of Uganda and Tanzania in the east. But the habitats
include a variety of environmental settings as mountains, rain forests etc.
Food habit
Chimpanzee eats termites, ants, caterpillars, bee larvae etc. They hunt
large animals and eat 15 species of mammals. However, Goodal reports
hunting and eating of 20 mammals species.
Gorilla Characters and Distribution:
Gorilla’s verity is of two types
a) Mountain gorilla and
b) Low land gorilla.
The average height of gorilla ranges from 5ft. to
6ft. The mountain gorilla is slightly taller than the
low land gorilla. While the average body weight
varies from 200-250 kg.
The average cranial capacity of male is 550 cc
and for female is 450 cc.Body is covered with
long shaggy black to dark brown color hairs.
They are the strongest and heaviest of all the
anthropoid apes. Facial portion is enormously
larger than cranial portion. Forehead very low
with prominent sagittal crest. Females have
weaker sagittal crest. Supra-orbital ridges form a
torus. Lower jaw is very massive. Canines are
very big, sharp and enormous size and
interlocking. Chin is absent. Hands are shorter
and broader than the other apes. Thumbs are
well developed. Foot anatomy indicates that they
are less adapted to arboreal life and shows
resemblance with man. Spend most of the time
on the ground but can climb on the trees. They
can walk quadrupedally for short time and distances. They are very
gentle but look ferocious and aggressive sometimes. They live in group
of 5-30 members where dominant male member become the leader of
the group. The dental formula is 2/2, 1/1, 2/2, 3/3.
Distribution
Gorillas are found distributed through the wide range of tropical forests
of Africa extending from Gambia in the north to Angola in the south, in
the west of Uganda and Tanzania in the east.
Food habit
George Schaller who observed Gorilla, he never show gorilla eating any
animal. Therefore, it is assumed that gorilla is totally vegetarian in food
habit.
Conclusion :
From the present study on the characters and distribution of anthropoid
apes, it may be concluded that these anthropoid apes possess some
salient features which is advanced from those of monkeys. Further,
among the four apes, Chimpanzee and gorilla spend most of their time
on the ground and chimpanzee reveals somewhat close to human
beings with respect to its anatomical and biochemical characters. These
anthropoid apes live in social groups. Chimpanzee and gorilla are
African apes, while gibbon and orangutan are Asiatic apes.