The site, which may roughly be dated to about 4000 B.C. has furnished archaeologists with sufficient material to undertake a somewhat detailed study of this type of man and his culture. The Pallemalala discovery is particularly important as it relates to a stone age society eking out a living in the island's coastal belt. Preliminary observations indicate that this stone-age population are genetically related to the Veddahs with whom they share many physical characteristics and cultural traits. Basing his inferences on recent soil profile analyses in Pallemalala and the adjacent region of Udamalala, he estimates that there are at least 50 such shell middens in the vicinity. Somadeva contends that the pallemalala midden was formed from the carapaces of molluscs gathered by primitive men from the surrounding area which appears to have been a dried up lagoon bed.
All indications are that a lagoon did once exist in the area at one time but had dried up later.
It seems to have been formed when the sea level in the southern coast rose sharply during some pre-historic period inundating the plains below. With the recession of the sea at a later date, those areas below the sea level where water had collected seems to have become an inland lake with thriving aquatic life. When the lake dried up, a layer of molluscs seems to have been formed in the bed, paving the way for their exploitation by primitives, contends Somadeva. Random sampling has revealed that as many as 99 per cent of the shells have been broken open, the vast majority of them through the intervention of some stone implement. Excavations going down to about three feet below ground level have revealed the living floor of the primitive settlers who seem to have followed a hunter-gatherer lifestyle closely resembling that of the Veddas.