Simple SummarySeascapes were the last environments to be discovered and mastered in the history of humankind. The adaptation to such environments therefore required the development of techniques considered as part of a set of distinctive innovations encapsulated in the concept of “modern behaviour”. This paper highlights the repeated catch and exploitation of toxic fish (e.g., Diodontidae, also known as porcupinefish in the Philippines), starting in the terminal Pleistocene ca. 13,000 years ago. The Bubog and Bilat archaeological sites yielded both cranial bones and dermal spines demonstrating that no preparation of the fish occurred immediately after the catch but rather that the fish were brought back to the camps. If not used for poison, these fishes would at least document the advanced knowledge to separate the toxic principle from the edible parts, which also implies a multi-stage cognitive process. Such knowledge was certainly one of the first steps toward the use of poison, meaning separating the edible parts from the toxic ones and keeping the latter for further use.AbstractRepresentatives of the Diodontidae family (porcupinefish) are known to have been fished by prehistoric Indo-Pacific populations; however, the antiquity of the use of this family is thus far unknown. We report here on the presence of Diodontidae in the archaeological sites of Bubog I, II, and Bilat in Mindoro, Philippines, dating back to c. 13,000 BP (Before Present). This evidence demonstrates the early exploitation by islanders of poisonous fish. Every part of porcupinefish can be toxic, but the toxicity is mostly concentrated in some organs, while other parts are edible. The continuous presence of Diodontidae remains throughout the stratigraphic record of these Philippines shell middens suggests that porcupinefish were prepared by human inhabitants of the sites to render them safe for consumption, indicating an advanced cultural knowledge of the preparation needed to separate the toxic principle from the edible parts. This constitutes one of the rare examples of poison processing by humans, aside from the contentious wooden stick poison applicator from Border Cave (South Africa).