This sloshing may explain why the mixing of genes in India seems to happen in layers between the same groups.28 Note that such non-linear movements are echoed in the later oral histories of many communities. The Gouda Saraswat Brahmins, for instance, claim to have migrated from the banks of the Saraswati River to Bengal and then later to the western coast of India. Long dismissed as myths, one wonders if these oral histories contain a memory of real population movements.
