New research suggests that the appendix, long believed to be a throwback to our evolutionary past, may serve an important purpose by boosting immunity and acting as a “safe house” for helpful gut bacteria.
For many men, getting an erection is as simple as breathing. But it's an incredibly complex process involving a precise sequence of psychological and physiological events that can easily go wrong. Here's how erections work — and how science is helping millions of men keep it up.
It's always amazing to look back at how terribly simple things once were. These pop-up books, for example, are intricately layered to show the various organs in a human body. Doctors would use 'em for practice surgery runs. [Laughing Squid]