Low-ranking individuals in a hierarchy suffer from higher basal stress levels and poorer health.

Chronic stress leads to hypertension and permanent damage to blood vessels, significantly increasing the risk of heart disease.

Stress disrupts the architecture of sleep and is a primary driver of clinical depression, as it exhausts the brain's dopamine and serotonin systems. Social Hierarchy and Stress

Stress is most damaging when the individual feels they have no control over the situation and no predictability regarding when the next "attack" will happen. Where to Find the Book

When a zebra is chased by a lion, its body initiates a massive, short-term physiological response to survive. Once the threat is gone, the zebra’s body returns to a state of rest.