Instincts present from birth, such as imprinting .
Chronic stress is a pathological state, not just an emotional one. From a veterinary science perspective, the hypothalamic-pituitary-adrenal (HPA) axis activation due to fear or anxiety has quantifiable physiological consequences:
Research in animal behavior traditionally focuses on four primary drivers, often colloquially referred to as the "Four Fs": (conflict/defense) Fleeing (predator avoidance) Feeding (foraging/nutrition) Reproduction (mating behaviors)