Their highly social behavior allowed them to accept a relationship with humans and to become part of a family group. Dogs have been used to herd and guard livestock, destroy rats, hunt, guard property, pull sleds and carts, apprehend criminals and perform rescues. They were used in wartime as message carriers. We can train dogs to be our eyes and ears, alerting the deaf to a ringing telephone and helping the blind cross a street. However, the most common and the most important of all the roles served is that of companion.
Dogs crave close contact with their owners and people form loving bonds with their dogs.
The companionship they offer helps ease the pain and isolation of the sick, the elderly and the physically handicapped. All dogs, regardless of breed, are essentially identical in anatomy. The skeleton of the domestic dog has about 321 bones, with variations in the number of bones in the tail and the presence of a dewclaw, an extra digit on the paw that not all breeds have. Rear paws have four complete digits and front paws have four or five digits. Most puppies have 28 temporary teeth, which are replaced with 42 permanent teeth at about six months of age.