ABOUT 10,000 YEARS AGO INDIA & SRI LANKA WERE CONNECTED BY LAND

ABOUT 10,000 YEARS AGO INDIA & SRILANKA WERE CONNECTED BY LAND AND AROUND 6000 YEARS AGO SRI LANKA EVOLVED AS AN ISLAND DUE TO CONTINUED SEA LEVEL RISE..
As the research of Rajiv Nigam indicated, sea levels continued to rise and reached the present level around 6,000 years ago. This is about the time Sri Lanka evolved as an island. Between 4,000 and 3,500 years ago, heavy rains, in addition to melting of snow, also contributed to the sea level rise. It rose by a couple of metres and fell to the present level about 2,000 years ago.
The last Ice Age had a profound influence on the prehistory of humankind. So in prehistoric studies of coastal areas, it is crucial to understand the consequence of changes in the sea level. About 14,500 years ago, the sea level was lower by 100 metres. With subsequent global warming and melting of large masses of ice, the level started rising, in stages.
As the sea level rose, the low-lying lands in the coastal region and the exposed continental shelves were inundated. This phenomenon gave rise to the stories and legends of deluges that permeated the African, Amerindian and Australian aboriginal folklore and Greek, Roman and Hebrew legends, and the Indian puranas, which referred to pralayas.

It is scientifically uncontested that the earliest Homo sapiens developed in Africa 100,000 to 200,000 years ago and migrated to Europe and Asia. Genetic evidence and fossil records of early human beings indicate that they came out of Africa as early as 100,000 to 60,000 years ago. Their descendants migrated to the Far East, probably along the coastal areas adjacent to the Arabian Sea and the Bay of Bengal around the Indian peninsula, Sri Lanka and then north into China and south into Sumatra. Global warming
The increased rate of global warming between 12,000 and 10,000 years ago saw the sea level rise almost 50 m, inundating low-lying lands and covering a major part of the exposed continental shelf. About 10,000 years ago, the sea level was about 50 m lower than the present sea level. At that time, the land extended about 25 km south of the Cape and the coast was about 40 km broader than the present coastline along the east and the west, which exposed about 1,000 sq km of land near Cape Comorin. Rameswaram and Mannar were joined by land and the land that extended in the present-day Gulf of Mannar was a 2,500-sq km stretch marked by sedimentary formations and coral reefs.

AN INUNDATION MAP by S.C. Jayakaran. He prepared the map on the basis of bathymetric contours and the sea-level curve for the central west coast to work out the configuration of the coastline south of India since the last Ice Age. It shows that about 14,500 years ago the sea level was lower by about 100 m than the present. The land between the coast now and the bathymetric contour of 100 m was the land that was exposed then.

Changes in southern India
It is possible to demarcate the land lost to the sea in the south of India from postglacial inundation maps that indicate the significant changes in the coastline.
The author has prepared inundation maps on the basis of bathymetric contours and the sea-level curve for the central west coast to work out the configuration of the coastline south of India since the last Ice Age. This study shows that about 14,500 years ago the sea level was lower by approximately 100 m than the present sea level. The land between the present coast and the bathymetric contour of 100 m roughly was the land that was exposed during that time.
In other words, hypothetically, if a 100 m column of sea water were to be removed, the land that went under water would be exposed. At that time the present Gulf of Mannar was a landmass of 36,000 sq. km connecting Sri Lanka with peninsular India and the coast was wider by about 80 km to the east, south and west of present-day Cape Comorin exposing a triangular mass of 6,500 sq. km adjoining the Cape. The coastline was 25-35 km wider than the present near Cuddalore and about 25 km wider near Colombo.
Extensive studies were done to understand global warming during the interglacial periods; sediments were subjected to meticulous analyses to establish the age and palaeo-geographical conditions in many parts of the world.
For instance, about 18,000 years ago, during the time of the last Ice Age, ice sheets in the poles spread much wider and the sea level was more than 100 metres lower than it is today, exposing a large area of land along the continental shelf. Then Siberia was connected to Alaska and along this land bridge, the peopling of the Americas and migration of animals happened over a long period. At this time, the landmass of present-day Papua New Guinea, Australia and Tasmania were joined together as were the British Isles with Europe. After the last Ice Age the level of the Indian Ocean, like the rest of the oceans, fell. Sri Lanka was connected to the Indian peninsula by a landmass, which now lies under the Gulf of Mannar. In the following 8,000 years, global warming continued and large masses of ice and glaciers melted, raising sea levels in stages and inundating low-lying lands. The portion of the continental shelf of the south Indian peninsula and the land that connected it to Sri Lanka also went under water as the sea level rose.