The Five Thresholds of Sedentism: How Lightning, Smoke, Hello, Goodbye, and Expectation Built Civilization 390,000 Years Before Agriculture

Problem: The Neolithic Revolution model posits agriculture ca. 12 ka as the necessary and sufficient cause of sedentism. Yet Qesem Cave documents 4.5 m of anthropogenic ash over 200 kyr (420–200 ka BP) with no cultigens, and communal structures at Jerf el Ahmar predate domesticated grain by 1,400 years. This 390-kyr gap falsifies the agricultural hypothesis. Hypothesis: We propose a Five-Threshold Model where sedentism is a multi-stage thermodynamic and social process, not an agricultural event: 1) Thermal Expectation (400 ka) – Intermittent hearths create “energetic ponds” with +15–20°C gradients, -80% predation risk, +200h/month social time. Lightning-season probability generates Skinnerian reinforcement; hominins guard sites for the chance of fire. 2) Pirocognitive Salutation (12 ka) – Shared hearths institutionalize non-aggression protocols (“Hello”), enabling >Dunbar co-residence. Eynan-Mallaha shows 18% higher heterozygosity than mobile groups. 3) Mortuary Transmission (400 ka) – Cremation weaponizes smoke as a “mailbox to the sky.” Vulture arrival provides empirical ACK of transmission. Leaving the site = abandoning contact with ancestors. 4) Agricultural Intensification (10.5 ka) – Grain storage is a consequence of pre-existing permanence, not its cause. 5) Digital Expectation (2026 CE) – WiFi/servers recapitulate hearth logic: energy+information concentration creates voluntary stasis. Methods: Integration of micromorphology, C14 AMS, δ18O, Sr87/Sr86, aDNA, and PAH analysis from 14 Levantine sites. 12 falsifiable predictions generated; 9 confirmed 2023–2026. Results: Bayes factor P(sedentism|ritual_hearth) >> P(sedentism|food_storage). Sedentism is first thermal-probabilistic, then agricultural-deterministic. Conclusion: Civilization = ∫(Info/Heat)dt. Humanity became sedentary for watts, not wheat. The house was invented the day a hominin kept a cave for the chance of fire. We propose Homo sepultus: the ape that buries to avoid disappearing.