Decoding the "Line of Fire": Traditional Ecological Knowledge of Feline Olfactory Encirclement and Spatial Avoidance Heuristics in Sumatran Tiger Coexistence

In the traditional Sundata community of West Sumatra, Indonesia, a highly specific taboo prohibits crossing tiger scratch marks (jajak kaisan cakar) that run transversely across human paths. The taboo is only about the prohibition of crossing transverse marks. The community knows the rule but does not know what purpose the taboo aims to achieve. When questioned, community members uniformly cite ancestral authority ("it is the elders' message") and vague warnings of disaster, admitting no knowledge of the technical mechanism. This specificity without explanation has long been dismissed by conventional science as mystical superstition. This paper presents the complete multi-year decoding journey using the SIGI EXPLORA methodology — a multi-perspectival framework predicated on critical inquiry as fuel, anti-bias as guardian, and radical data inclusivity. The study documents the iterative process of discovery, including the initial failure to obtain technical explanations, the systematic collection of data regarding what is and is not prohibited, and the critical thinking trace that began by examining the scope of the taboo. When observing this taboo with critical thinking, I began by examining its scope. Its scope is limited to transverse tracks. It is not a taboo to continue a journey if encountering tiger tracks. For Sundata farmers, finding transverse claw scratch tracks is very rare, but finding tiger footprints on the road to farms happens almost every day — even often farmers going to farms in the morning see tiger footprints along the road, sometimes the tiger stepped in a puddle and the water is still rippling, indicating the tiger walked 20-25 meters ahead on the same road. This condition is not taboo to continue the journey. This comparison made me want to know the basis for a taboo that is so specific and rare. Through investigation via questions to elders who believe in the taboo, I found that because the taboo is specific to transverse tracks, tracks that are not transverse are not prohibited. That specificity is the crucial point that brought me to the belief that this taboo is not merely myth but has its own purpose. The breakthrough came from an elderly traditional hunter describing olfactory encirclement — a sophisticated tiger hunting strategy involving the creation of invisible scent barriers to manipulate prey movement. SIGI EXPLORA's convergence validation reveals that the transverse scratch mark is not merely a territorial marker but a physical segment of an olfactory encirclement barrier. The human path happens to intersect the tiger's invisible "scent circle" during active hunting operations. The taboo thus functions as a highly accurate spatial avoidance heuristic designed to keep humans out of the predator's "Line of Fire" or "Kill Zone." Entering this zone presents three life-threatening risks: (1) mistaken identity, (2) resource competition, and (3) defensive aggression. The transverse scratch taboo represents a second Coexistence Standard Operating Procedure (SOP) — distinct from the palongang refuge-protection taboo documented in a companion study — demonstrating that ancestral knowledge systems encoded sophisticated understanding of predatory behavioral ecology, specifically the use of olfactory manipulation in ambush hunting strategies. This represents quintuple genius: simultaneous understanding of (1) tiger behavioral ecology, (2) predatory hunting strategies, (3) spatial risk assessment, (4) cultural psychology, and (5) cognitive heuristics for life-saving spatial boundaries. Together with Palongang (ETB-26-0208, submitted to Journal of Ethnobiology 04-Nov-2026), Adat Death Penalty, Quarantine via Ditch and Clothesline, and Toothache Tiger, this taboo forms a complete invisible management system that successfully maintained human-tiger coexistence for millennia. Rejection of taboos as myths by modern researchers is neglect of important data for understanding local wisdom that created coexistence with tigers and Sumatran nature. Companion Paper: ETB-26-0208 - The Palongang Paradox - Journal of Ethnobiology Author: Egis Adri - SIGI EXPLORA Research Initiative, Sundata Village, Pasaman, West Sumatra, Indonesia - ORCID: 0009-0007-3654-5001