Sundaland is a landmass influenced by tectonic and sea-level fluctuations during the Pleistocene. Song Gede (SGD) on Nusa Penida Island located on the south-eastern corner of Sundaland, towards Wallacea. It was a strategic dwelling cave occupied from the Late Pleistocene onwards. This study aims to recognize the history of human occupation and adaptation during the transition of Pleistocene-Holocene in the area based on dental records. This work characterizes two-second lower molars using comparative morphology (ASUDAS), BL and MD measurements. We test their similarities and variations through metric and non-metric statistical analysis, and place them among prehistoric and recent Homo sapiens samples from the Indonesian archipelago. Identical molar morphology shows the same population inhabited Song Gede for an extended period. SGD (48) dates from the Late Pleistocene (18 Ka BP) and is associated with a hunter-gatherer population subsisting on large terrestrial mammals such as bovid, deer and pig. SGD (16) is of Mid Holocene age (5.373 ± 28 CalBP) and has significant buccolingual reduction compared to the Late Pleistocene sample. It suggests diet change to aquatic sources as a result of local adaptation and evolution to an insular habitat following the drowning of the Sunda Shelf. However, the results indicate that both SGD (48) and SGD (16) are closely related to anatomically modern human and pre-neolithic populations affiliated with recent Australo-Melanesians. This information provides a useful overview of human biological adaptation on the edge of Sundaland, across the Wallacea during Terminal Pleistocene to Holocene.