Our hard-wired stress response is designed to gives us the quick burst of heightened alertness and energy needed to perform our best. But stress isn't all good. When activated too long or too often, stress can damage virtually every part of our body. Sharon Horesh Bergquist gives us a look at what goes on inside our body when we are chronically stressed.
To look at the evolution of modern bird feathers, we must start a long time ago, with the dinosaurs from whence they came. We see early incarnations of feathers on dinosaur fossils, and remnants of dinosaurs in a bird's wish bone. Carl Zimmer explores the stages of evolution and how even the reasons for feathers have evolved over millions of years.
Have you ever heard that you become more powerful in life-or-death situations? There are a lot of anecdotes about super strength, but is it a real thing?