PBS Eons has a new episode, which is about chili peppers.  It looks at how and why they got hot?  And, why do we love it…

Today, chilis are the most widely cultivated spice crop in the world – grown everywhere from their native home in the Americas to Europe, Africa, and Asia. But how and why did chilis evolve this weird, fiery trick in the first place? And why did we learn to love that spicy burn?