Dogs are awesome. They were the first species to be domesticated. 
They are awesome! I find it amazing how many species are in existence.
There are so many because they have been selectively bred over thousands of years for various behaviors and physical attributes
This is true, I personally prefer bulldogs. Did you know the American Bulldog was bred to hunt boar?
Interesting, I did not know that. Dogs perform lots of roles for people, such as hunting, herding, protection, and companionship 
Yes, they do. Some are smarter than others. Like the Boarder Collie, they are the smartest dog breed.
Border collies are so cute! I like German Shepherds. They are common in assisting police and military