“History begins with written records. But if we want to study the story of the period without any trace of writing we must, in that case, take the help of the unwritten evidences of nature”.Dr. R. M. Sarkar
In this vast area of nature, we can decode our unwritten organic history of our remote past by means of fossilised remains. So here come the question is, what is fossil? Simply fossil are the hard parts of animals or plants which have been infiltrated by mineral substances, present in the layers of the earth, and turn into stones. The term fossil has been derived from the Latin word Fossilis, which means to dig up. In respect to anthropological view point, we restricted our term to fossilized bones of animals and man.
Let us understand how fossils form, in general the flowing water carriers sand, mud and various other materials and deposit these in layers on the floor of the sea or lakes. As sand is the heaviest material, hence it settle first on the bottom to form sand stone in due course. Then comes the mud down and after sometime it become harden which is known as shale. The remains of the different animals also deposit with these and form limestone. This accumulation of slowly deposited layers or strata is known as the sedimentary or stratified rocks. And the process continues, the lower layers of the stratified rock are more ancient than the upper ones. The geologist have been able to arrange the stratified rocks of the world in a series , according to their age, from their examination it has also been possible to find out the correct estimate of the age of different strata, and therefore we get an idea about the chronology of the different animals found fossilized in the different strata.
In respect to scientific study, the stratified rocks not only present us the remains of an animal to study its anatomical characters, but it also gives us something more. When we discover a fossil man from any stratum, we get side by side many others valuable evidences such as, remains of others animals and plants, stone implements and other works of man, which help us in studying the climatic conditions and culture of that period.
Following are the important fossil primates that we study in anthropological point of view to understand our evolutionary significance.
- Lemuroids : The fossil lemurs have been found from the lower Eocene deposit onwards in the soils of both new and old world.
- Tarsioids: The fossil tarsioids have been found in the Eocene beds of Europe and North America. The size of these animals is not bigger than that of the mouse.
- Parapithecus: The Eocene and Oligocene deposit at Fayum in Egypt, are regarded as the paleontological treasures.
- Propliopithecus: The Propliopithecus is represented by fossil jaw fragments discovered from the Lower Oligocene bed at Fayum.
- Pliopithecus: Pliopithecus antiquus was discovered by Lartet, in the year 1837, from the lower Pliocene bed in Germany.
- Lemnopithecus: This fossil has been discovered by Hopowood in the Miocene deposit from Kenya.
- Proconsul: Proconsul africanas was represented by a crushed palate and part of the facial region of an adult, a juvenile mandible, a more or less complete adult mandible, and three torasl bones. These were found in the Miocene deposit in Kenya, East Africa.
- Dryopithecus: In the year 1856, Lartet discovered from the Miocene deposits, in South France , a lower jaw bone which was assigned to the genus Dryopithecus. There are about 12 different species of Dryopithecus so far discovered.
- Oreopihecus: Oreopithecus bamboli was discovered from brown coal or lignite deposits in Tuscany in the year 1872. The skeletal present many hominid features. The bones of the pelvis and of the legs possess such characters that found among the animals capable of bi-pedal locomotion.
Courtesy: The present article is the reproduction of the work of Dr. R.M. Sarkar from his famous book “Fundamental of Physical Anthropology” Second edition 1970.