Today’s Wonder of the Day was inspired by danni from AL. danni Wonders, “what can dogs smell when they smell fear” Thanks for WONDERing with us, danni!

Do you love dogs? We do! There's nothing quite like being greeted by a furry friend with a wildly-wagging tail. It's no WONDER they're called man's best friend. Through thick and thin, your dog is there to give you unconditional love.

But not all dogs are friendly. Most people have come across an aggressive dog at one time or another. When that happens, some people will tell you to remain calm and not to show any fear. Why? Because dogs can smell fear! If they smell fear on you, they'll become more aggressive and possibly attack.

Is that true, though? Can dogs really smell fear? After all, fear is an emotion, like happiness or sadness. Can dogs smell an emotion?

Experts who have studied dogs and their sense of smell have concluded that dogs can't necessarily smell the emotion that is fear. They can, however, detect smells and see movements and body postures that may help them sense when a person is nervous, anxious, or afraid.

Anyone who has spent much time around dogs knows they have an incredible sense of smell. Bloodhounds, for example, have a heightened sense of smell that is at least 1,000 times stronger than a human's.

When we get scared, we tend to sweat more. Our bodies also produce more adrenaline and release certain chemicals, such as stress-related hormones. Given dogs' impressive sense of smell, there's no doubt that dogs can detect the scents of sweat and these other chemicals.

However, smelling sweat doesn't necessarily mean the same thing as smelling the emotion of fear. Experts believe that sensing fear may involve more than smells. Movements and actions, such as stiffening up or staring straight at dogs, can be seen and interpreted by dogs to lead to a conclusion that a particular person is afraid and therefore may present a threat.

Rather than smelling fear, it's probably more accurate to say that dogs can sense fear. And sensing fear is probably a mixture of smelling sweat and other chemicals combined with interpreting body language and other movements.

Like dogs, humans can also interpret body language and sense emotions in others. But can they smell things like dogs can? Maybe! Recent research has indicated that human sweat from anxiety smells different than sweat from exercise…and humans can smell the difference! Researchers believe that humans may be able to detect certain smells associated with anxiety and react with empathy as a result.

Wonder What's Next?

Tomorrow’s Wonder of the Day looks back to a time when scientists wanted to be magicians!