Debate surrounding Neanderthal extinction has long stalled between two opposing, mutually exclusive explanations: climate-driven population collapse, or competitive displacement by anatomically modern humans (Homo sapiens). Drawing on the Local Survival and Evolutionary Dispersal (LSED) theoretical framework, this paper introduces a quantifiable analytical metric – the Energy-to-Information Conversion Rate (EICR) – and puts forward a population system collapse hypothesis to resolve the deadlock. Neanderthals evolved robust, static cold-adapted physiology, with drastically elevated total daily energy expenditure (TEE). Their social structures, however, were trapped within rigid, low-dimensional steady-state systems, yielding extremely low EICR values. The vast majority of their metabolic energy was channelled into bodily thermoregulation and physical labour, leaving negligible resources for processing environmental data or sustaining inter-group co-operation. By contrast, early Homo sapiens underwent repeated rounds of adaptive evolution amid the volatile MIS 3–2 climate transition, building dynamic, widely distributed social networks defined by high EICR. Ancient whole-genome sequencing highlights a fundamental divergence in population bottleneck signatures between the two hominin lineages. Neanderthal groups display sustained, irreversible genetic contraction; modern human populations show episodic, recoverable bottlenecks – direct empirical proof of the stark gap in systemic resilience when faced with frequent, abrupt swings between cold and warm conditions. This paper argues Neanderthal disappearance was not merely a by-product of interspecies competition. Instead, it represents an inevitable thermodynamic breakdown: their low-EICR steady-state systems could not maintain a closed energy-information conversion loop when subjected to repeated Dansgaard–Oeschger (DO) cold-warm perturbations.
Jing Zhang (Sun,) studied this question.