What is the connection between the Mahabharatas Tarpan and modern Pitrupaksha practice?

The Mahabharata established Tarpan — the offering of water mixed with sesame seeds — as the simplest and most universally accessible form of ancestral offering. Bhishmas Anushasana Parva teachings describe Tarpan as sufficient when more elaborate Pind Daan is not possible. Modern Pitrupaksha practice follows this graduated approach: daily Tarpan throughout the sixteen days, with full Pind Daan on the ancestor death tithi, and Sarva Pitru Amavasya as the comprehensive final offering.