Dogs are members of dogs, which are part of the wolf like dogs and are the most abundant predators. Dogs and the existing grey wolf are sister groups. Modern wolves are not closely related to the first domesticated wolves. The dog was the first domesticated species to undergo thousands of years of selective breeding with a variety of behavioral, sensory and physical attributes.

Their long-term interaction with humans has made dogs have a unique impact on human behavior. They can grow up through a diet rich in starch, diete, which is not enough for other canine animals. The shape, size and color of dogs vary greatly. Dogs play many roles for people, such as hunting, herding, loading, protecting, assisting the police and the army, accompanying, and recently helping the disabled. This kind of influence on human society makes them "the best friend of human beings".

Dogs have been selectively bred for thousands of years due to a variety of behaviors, sensory abilities, and physical attributes. Modern dog breeds exhibit larger size, appearance, and behavior variations than any other domestic animal. Dogs are predators and scavengers. Like many other predatory mammals, dogs have strong muscles, fused carpal bones, cardiovascular systems that support sprinting and endurance, and teeth that can be captured and torn.

Dog's senses include vision, hearing, smell, taste, touch and sensitivity to the earth's magnetic field. Another study shows that dogs can see the earth's magnetic field.

Here you can download free pictures of dogs and puppies