The purpose of Evolution and Natural Selection is to reward those characteristics in a species that enhance its ability to survive [and penalize those characteristics which are do not contribute to the survival quotient]. So the original giraffe’s neck grew longer and longer as Nature favored those giraffes which had long-neck genes. Because a long neck meant the ability to reach the leaves on the higher branches of the Acacia trees on which the giraffes fed, longer neck giraffes ate more, were healthier, and were more able to find mates. The genes which promoted the long necks were passed on, and over the generations, the necks of giraffes grew longer and longer.
In general, animals evolved to have characteristics which enabled them to more successfully find food, find a mate, or adapt to the climate or geographical conditions of their environment. But Dogs are unique in that in they evolved to have characteristics that endeared them more to Man. Of course there were working dogs and dogs which were useful in helping Man hunt, or pull a load or protect his family and possessions. Though the characteristics of the various breeds of Dogs can still be seen in each Dog, today the most important function of Dogs is to be a pet and companion to Man and his family. Most people don’t buy a Golden Retriever for hunting, or a Bloodhound for sniffing, or a Greyhound for racing. Most people buy a dog because it is an amiable companion with an agreeable disposition, more so to them than many of their human friends and realtives. A dog does not normally throw tantrums, a piece of meat will satisfy a dog more than a diamond would satisfy your girlfriend. A dog cares not whether you are a millionaire or a pauper, and a dog would not leave you if you become poor overnight. A dog would stick with you through thick and thin, unlike your human friends.
Why is a dog the King in terms of its ranking in the survival of species stakes? Because a dog does not have to worry about hunting for food. All it has to do is to look and act cute and Man, the Master of this Universe will be his Slave and provide him with food and shelter. No other animal [except perhaps to a lesser degree the household Cat] is able to do this so successfully. A Dog is the ultimate in natural selection success, a species that showcases the efficiency of evolution by natural selection. No need for it to worry about having longer legs to catch faster prey, or bigger ears or keener noses for hunting it’ s food. More important that it should run up and greet its owner, slobbering him/her with licks, looking even happier than it’s owner’s mate would be at seeing him/her. A dog should also be able to whine, cast soulful eyes and invoke sympathy when it has done something displeasing to it’s owner [such as chewing up the sofa], and it’s owner would then feel guilty about being angry with the dog, and give it even more food.
The whole dog-owning industry must be worth many billions of dollars as owners compete to feed and care for their dog with the best food and medicine, toys, exercise facilities and even clothes. As a man/woman ages, and children live the family nest, a dog becomes even more the focus of attention, a substitute child to care and lavish your attention on, and even to bequeath your fortune to. Even Man is not as highly evolved as a dog if you define the ultimate aim of evolution as fitness to survive. Man still has to use his brains to earn his living to buy his food. A dog does not have to do anything but be a companion to Man and his family.