Darwin's declaration regarding the descent of man from non-human ancestors caused a great deal of controversy among the scientists and the general public of those times. It was a matter of great degradation when any attempt was made to draw any line of relation between Man and Apes. However, in due course, with newer inventions and discoveries in this area, Darwin�s views were accepted by all and thereby the people were forced to embrace their strange relatives.
Apes and Man are members of family Pongidae, Hylobatidae and Hominidae. The belong to the suborder Anthropoidea and the order Primates. The relationship of apes and man will be understood if attempts are made to study the various anatomical features critically.
The skulls present many contrasting features such as:
The apse lips are thin and the red portion of the lips are rarely seen when mouth is closed. The integumental lip has little quantity of fat.
In apes the arms are greatly elongated, an adaptation to the habit of hanging and walking in branches. In apes upper arms act as movable levers and hence the length is short and in man lower arm is movable lever and hence shortened.
The femur (Thigh Bone) of ape is short, thick and curved. In man it is long slender and elongated. The ridges for muscle development in femur are greatly developed in man than in the apes. The linea aspera, a rough ridge on the back side of the femur is characteristics to the man.it has resulted due to great development of of the extensor muscle which play a important part in erect posture and the bipedal gait.
Brain in man is not only much larger than that of apes but also highly developed. The weight of man�s brain is three times as heavy as that of a gorilla, the largest ape. The frontal region of the human brain is especially developed and the cerebral cortex presents a much more complex development than that of the apes.
The brain case in the man is largest ranging from 1300 to 1450 cc. the average cranial capacity of gorilla is 549, chimpanzee 400, orangutan 416 and gibbon 98 cc respectively.
Man is distinguished from the apes mainly by his ability of articulating speech. But there are some scientists who has felt that the use of some sort of language among apes.
In hands, feet and pelvis along with size of brain the gorilla shows close relationship with man. But the massive jaws of the gorillas have no resemblance with those of man.
Their resemblance covers the likeliness of the skull and pigmentation of the body. The chest portion of the Chimpanzee is almost human.
In his high forehead and the same number of pair of ribs the orang shows similarities with man. On the other hand , two factors like the shortness and degenerate character of the legs and The adaptation of the feet for suspension, separate these two individuals from each other.
The length of leg and the erect gait of the gibbon indicates its closer relationship with man, anatomically.
But in other characters like excessive arm lengths, general size, pelvis, hands and feet, length of canine teeth and the size of brain, the gibbons goes farthest from the man.
Among the four apes it is seen that each of them have developed one or more special features, with which it can demand as closest relationship with Man.