The insular region of Wallacea has become a focal point for studying variability in early modern human adaptation to island environments under changing climatic and ecological conditions. Here we focus on how early socioeconomic adaptations influenced belief systems and burial practices of past foragers at Ratu Mali 2, an elevated coastal cave site, on the small depauperate island of Kisar. We utilize multidisciplinary methods to reconstruct maritime adaptations at Ratu Mali 2 (15.2-3.7 ka) which span significant climatic changes and contains faunal, lithic, and shell artifact material as well as the earliest burials recorded in Wallacea. These data indicate that the cognitive capability of our species in evolving significant marine subsistence behavior in combination with establishing open sea voyaging, and trade and exchange networks under changing climatic conditions, gave our species an edge. The two individuals interned (14.7-15.2 ka) in an identical flex primary position subsisted on a greater marine/C4 diet compared to other individuals in Wallacea during the Pleistocene. The earliest evidence for mortuary practices in Wallacea at Ratu Mali 2 indicates that these maritime adaptations facilitated symbolic ritualized treatment of the dead in the most marginal of island environments.