India, Aug. 1 -- How do we honour our dead? Around the world, and through history, the answers have varied.

The earliest signs we know of involve fragments of petals found at gravesites in a cave in Israel, dating to over 13,000 years ago. Stone memorials, from little cairns across Europe to the dolmens shaped like huts spread across peninsular India, date to between 8000 and 3000 BCE. These would evolve, over time, into crypts, memorial plaques, commemorative busts, tombstones.

Amid this timeline, about 2,300 years ago, a new kind of memorial began to dot the ancient Tamil-speaking landscape, appearing in parts of modern-day Tamil Nadu, Andhra Pradesh, Telangana, Puducherry, Kerala, Karnataka, and as far as Lakshadweep and Sri Lanka. ...