2. Evolutionary Angle
Primal instincts: Saliva production is a survival trait — it protects your teeth, aids digestion, and signals readiness to eat. Drooling might be an overflow mechanism in a deeply relaxed (safe) state, suggesting that the body doesn’t feel threatened.
Animal behavior: Many animals drool when asleep, hungry, or relaxed. Humans likely retained this as a side effect of muscular relaxation during rest.
