Stress was once the reason our ancestors survived sabertooth tigers, and now it’s the reason we panic over emails.

In the latest video from Kurzgesagt, the team breaks down how this ancient survival mechanism turned against us, quietly draining our health and happiness in the modern world. What started as a life-saving “fight or flight” response has become a 24/7 alarm bell that never turns off.

Here’s how stress evolved, why it’s wrecking your body today, and how you can reclaim it as the superpower it was always meant to be.