Dogs are an incredibly diverse species. Not only do they have an amazing array of of physical characteristics, but even their personality traits and behavioral characteristics differ from one breed to another.

Much of this is down to human meddling. For centuries we have bred dogs to meet our needs, so that over time we've developed over 600 distinct dog breeds.

However, recent studies suggest that many of the physical changes in dogs may have occurred spontaneously. So as amazing as it is, it seems dogs have actually evolved along the lines they believe we expect of them. Now that's what I call devotion!

Fascinating stuff, but there's also a practical purpose to all this.

Let's say you are interested in buying or adopting a purebred dog. I'm sure you'd want one that is a good fit for your life style. It would be foolish for example to adopt a Husky, if your idea of fun is flopping down in front of the TV with with a bowl of popcorn. Before you know it you'll have an extremely frustrated dog, most likely with behavioral problems.

By the same token, an active person who gets a Bulldog and expects him to join in the Sunday morning jog is bound to be disappointed.

And it's not just energy levels you need to consider. As you begin to put together a picture of your perfect dog, think about the level of affection you want, the level of independence, guarding ability, whether you mind a dog that barks. You'll find there's a breed that matches just about any profile you can think of.

And what about physical appearance, size for example? It's hard to imagine two animals more different than a Saint Bernard and a Chinese Crested, yet both are unmistakably, dogs.

Another factor you need to take into account is the amount of hair the dog sheds. Some dogs shed enough hair to make another dog, while others hardly shed at all. And if shedding is really an issue there are hairless dogs, like the Xoloitzcuintle.

Trainability is another factor that should be considered. If you're determined to obedience train your dog, then you'll want a breed that is pliant and obedient, not the canine equivalent of an obdurate mule.

So if trainability is an important factor you'll want a dog that is a quick learner with an eagerness to please. Dogs that fall into this group include the Poodle, Papillon and Golden Retriever.

At the other end of the scale you'll find the hounds - stubborn, obstinate and downright bloody-minded. Dachshunds are said by some (only half-jokingly) to be impossible to train, while some toy dogs just can't be bothered to pay attention.

And then there are the so-called designer dogs, as well as mixed breed dogs, which we haven't even spoken about here.

The point is, there's a dog that's ideal for every person, every lifestyle. What's your dog type?