Dawn and Devolution of the Indus Civilization
by S.R. Rao
The author puts forth convincing evidence to prove that the decline of Indus Valley cities was not due to the invasion of barbaric Aryans unsympathetic to civilization, but due to natural calamities such as floods, desiccation and tectonic activity. A strong Aryan substratum was already present in the Indus Civilization during its early days, and continued to the last, leaving its indelible impression on the fabric of Indian culture. Tired of natural disasters the Harappans migrated to the Saraswati (Ghaggar), Drishadvati (Chautang), Yamuna and Gang valleys in the East and to Gujarat and Narmada valleys in the South.
“Shikaripura Ranganatha Rao (1 July 1922 – 3 January 2013), commonly known as Dr. S. R. Rao, was an Indian archeologist who led teams credited with the discovery of a number of Harappan sites including the port city Lothal and Bet Dwarka in Gujarat.” —Wikipedia