By Peggy R. Lott on May 12 2018 03:38:45
Dogs have been selectively bred for thousands of years, sometimes by inbreeding dogs from the same ancestral lines, sometimes by mixing dogs from very different lines. The process continues today, resulting in a widening in appearance without speciation, "from the Chihuahua to the Great Dane."
Some breeds have so much energy and are so active that if you do not give them a sufficient workout every day - a long walk and hard run - their pent up energy will quite likely manifest itself in destructive behavior.
Today there are over 400 recognized breeds of dogs in the world. Many of them have historical origins dating back hundreds, even thousands of years. Wherever humans have lived, dogs have been alongside them performing various tasks. One of the reasons dogs have been such a successful species is because they are so adaptable. They have made themselves useful in countless ways to humans so we kept feeding them, providing shelter for them, and, yes, breeding them. It’s no accident that we have dogs able to hunt, herd, guard, track, and do so many other things at an expert level. Humans figured out early on that if you bred dogs that were good at these things, you would get offspring that were also good at doing them. All of these jobs performed by dogs were necessary for our own species to survive. It’s no secret that we owe a lot to dogs, just as we do to other animals.
Dogs with short coats also have another advantage. It is easier to find ticks and fleas on their body. You probably spend eight times as long searching for fleas and ticks on a dog with a long coat than you do on a dog with a short coat.