Reviewed by Dr. Becker

You'd likely consider this anything but normal. Yet it's a normal physiologic process — not a disorder at all. It could actually be an ingenious design of nature. Here's how to diagnose it, and how to be sure it's not accompanied by a life-threatening bacterial infection.

It's invisible to you, but these dogs can pick up on it and warn their owners or family members of a looming medical emergency. The dogs' warning methods are fascinating and they can even be trained to call 911 themselves, if necessary. Could one save your life?

You already know that dogs are in tune to human emotions, but how about among their canine partners? What happens when they perceive their buddy is distressed? Their reactions are just more proof of how loving, sensitive, and intelligent dogs truly are.