Have you ever wondered what makes you right- or left-handed? Well, in humans and other mammals, the brain is divided down the middle, or `lateralized'.
Nostrils. Your dog has them. Two of them actually. And you don't give them any attention, do you? Sure, you might take your dog to the vet when you see gunk coming out of them, but on any given ho-hum day, you're not giving your dog's nostrils a second thought.
You may have heard the claim that left-handed people are smarter than right handed people. Specifically, it seems that left-handed people are over represented in musicians, architects and art and music students.