During the first quarter of this century, not much was known about the Indian Stone Ages and only two phases, Palaeolithic and Neolithic (including microliths), were recognized. Some of the earlier discoveries recorded by Robert Bruce Foote, Coggin Brown, Cammiade, Miles Burkitt, De Terra, Paterson and others gave an impetus for the later researchers and the Stone Age cultural sequence began to take a clear shape. The most significant among the later discoveries is the identification of a distinct culture by H. D. Sankalia, which is now designated as the Middle Stone Age, and the extent of its distribution is now well established. Prehistorians who launched a systematic survey unearthed the remnants of the stone using populations from different parts of the country, viz., the Panjab, Rajasthan, Uttar Pradesh, Bihar, West Bengal, Orissa, Madhya Pradesh, Maharashtra, Gujarat, Mysore, Andhra Pradesh and Madras recognizing three phases, The Early Stone Age, the Middle Stone Age and the Late Stone Age, occupying the time span of Pleistocene and Early Holocene times.The material culture that represents the Stone Age Communities in various parts of the country displays a homogeneous pattern of development. The Early Stone Age is followed by the Middle Stone Age which in most of the regions gave way to the Late Stone Age; however, a blade and burin industry with a discontinuous horizontal distribution is known in a few regions between the Middle and Late Stone Ages.
New investigations at the Middle Stone Age site of Pockenbank Rockshelter, Namibia