Dog are the best pet you can have. Despite the fact that they are messy and barks during the night but there are the best and really loyal to their owner. The way you can tell their are happy is when they wail their tail sideways. And they are actully mentioned many times in the Bible. The average dog can run about 15-19 miles per hour at full speed but if there are not active and overweight there would run about 1 or 2 miles before they get tired. And the dog sense of smell is way stronger then a average human and hearing is way stonger too. People have been keeping dogs for pets for a long time like in the middle ages. A female dog carries her baby for two months before the baby is born.