So let’s set the stage – what are the facts and figures?
Dogs are definitely human’s best friend. There are estimated to be 400 million dogs currently in the world. The most popular breed is the Labrador, and the most common dog name is Max. Dogs were first domesticated around 15,000 years ago, and their first role was to help hunters track food and help protect the settlements, in exchange for scraps of food and some shelter. Dogs have since evolved, developed and been bred into all shapes and sizes, and all manner of roles and jobs. The biggest recorded dog was Zeus, the Great Dane, who when standing on his hind legs was 2.2m tall and weighed over 70kg. The smallest recorded dog was Boo Boo, a Chihuahua who was 10cm tall and weighed less than a kilogram.
And the toughest dog is probably Cairo, who currently serves in active duty with Seal Team Six and is known for his love of helicopter rides and high altitude parachute jumps, as well as playing fetch using bad guys rather than tennis balls. Although historically he’s probably up against some tough competition from Sergeant Stubby, who served in four offensives on the Western Front in World War I, saved numerous lives by detecting and warning of incoming gas and artillery shells, and apparently single-handedly caught a German spy and held him by the seat of his pants until reinforcements arrived. Stubby returned home a war hero, participated in numerous parades, met three American presidents and was awarded two medals.
But what about their senses – do dogs really have super hearing and smell?
Dogs can definitely hear and smell much better than us. Dogs can hear sounds roughly four times further away than humans, and can detect much higher pitched sounds than people. In addition, dogs can swivel their ears to better detect sounds from one angle while blocking out noise from other angles. But where they really excel is in smell. Amazingly, dog’s nose is approximately one million times more sensitive than a person’s. And what’s more, they can detect which way the wind is blowing, and where the smells are coming, by feeling the breeze on their wet nose.
So if it’s true that they have such amazing senses, why can’t dogs see colour?
This is actually not correct, dogs can definitely see colour. However, dogs aren’t as good at seeing colours as humans are. There are two types of visual receptors in our eyes – rods and cones. Rods detect black and white and movement, whereas cones detect colour. Dogs have evolved to have far more rods (black and white) and less cones (colour) than we have. So can’t see colour as well as us – in fact they are red-green colour-blind. But there’s a reason… their rods give them much better vision when it is dark, and the rods also make them extremely good at picking up movement. And this makes dogs excellent hunters, especially at night.
On the subject of eyesight, my dog doesn’t seem interested in animals on television, but loves playing with other dogs outside. Why?
Ah, well noticed. The eye rod receptors (for black and white and movement) are responsible again. Dogs have very high numbers of these rods, and are far better at seeing movement and change than we are. Most of the older televisions tend to refresh, or update, about 50 times per second. Our human eyes aren’t good enough to see this change, but dogs are, so the television image looks like it is flickering and blurry. However, there is some good news. The modern top-of-the-line flat screen televisions refresh at over 100 times a second, which is perfectly adequate for a dog to watch – a great excuse for buying yourself that new television.
So their senses are pretty good, but how clever is my dog?
It’s very difficult to make an exact comparison between dogs and people. Dogs excel at some forms of intelligence, such as social and emotional intelligence, and in some respects are far more perceptive about their mates we humans are. On the other hand, even the smartest dogs can’t do algebra. This is because dogs have evolved in to enhance different aspects of their intelligence than us. Dogs live in a pack hierarchy structure, with an alpha dog at the top and a number of beta animals below. They have developed a number of complicated verbal, visual and olfactory (smell) based cues to communicate signals and co-ordinate their actions during hunts and while at camp. This means that in our domestic situation, dogs are very canny about our social order, maybe more so than we humans are. In fact, the family dog will have a detailed mental breakdown of the entire family order, from who they see as the top of the house, right down to who they see at the bottom. They will also have a place for themselves on there.. and their opinion on their position may surprise you.
I’m not really sure my dog is that clever though, is there any difference between breeds?
Definitely some breeds are more intelligent than others. This is partly due to selective breeding, and partly due to chance. There have been a number of dog intelligence tests developed, which generally involve memory, command learning and reasoning. The most intelligent breeds are Border Collies, German Shepherds, Standard Poodles and the Retrievers. And I’m afraid the lowest scoring on these tests is the Afghan Hound. But as the owner of a loyal and lovely but not particularly bright dog, I can attest that he certainly seems pretty happy and has his life rather well sorted out to his liking. So maybe the IQ tests aren’t the final word.