Persistence

Biological Parallel

Mammals that survive predator attacks retain vivid, intrusive memories of the threat—rats exposed to predator odor show persistent stress responses months later. African elephants orphaned by poaching display PTSD-like symptoms decades later: hypervigilance, abnormal aggression, and persistent fear responses to vehicles resembling those used by poachers. Thomson's gazelles that survive lion attacks become 'trap-shy,' avoiding that specific water hole for years even when safe. Traumatic memories resist normal decay because they signal rare, high-stakes pattern breaks requiring permanent behavioral adjustment. Persistence is adaptive hypervigilance: the brain tags certain experiences as 'never forget' because the cost of repetition is death.