Genetics & the Social Behavior of Dogs

Molecular evidence shows that all domestic dogs descended from the gray wolf about 130,000 years ago, according to the Public Broadcasting Service. Through years of selective breeding, the dog that we see today evolved. The domestic dog retains the social behavior of its wolf predecessors. Its ability to develop complex social relationships makes the dog an ideal companion for humans.

  1. DNA

    • At least 150 breeds of dogs exist around the world. They range from the tiniest Chihuahua to the towering Irish wolfhound. Each breed exhibits its own physical characteristics and personality traits. These variances are a direct result of the breeding that has taken place to develop the individual breeds. Today the DNA remains virtually identical between the wild wolf and the domestic dog, according to the National Geographic. Skeletal fossils of dogs exist on all continents except Antarctica.

    Domestic Dog Breeding

    • Dogs have evolved to live and survive in their environments. As the lives of dogs and humans became more entwined, humans decided to reproduce the dogs for desirable physical and behavioral traits. Some breeding endeavors focused on reducing the dog's size by breeding smaller and smaller specimens; others bred for behavioral characteristics, such an excellent hunting ability or defensive aggression.

    Pack Behavior

    • Despite the generations of breeding and the wide variety of physical characteristics, the domestic dog retains its social wolf behaviors. The dog craves life within a social pack system, just like the wild wolf does. Some dogs demonstrate an alpha character that gives them the ability to lead a pack, but others have the personality of a follower. A subordinate dog will submit to the alpha dog's leadership, just as a would submit to the leader of its pack. A domestic dog exists peacefully within a human family because of its genetic predisposition for pack life. The dog will consider its human the alpha leader. The genetic-social behavior of the dog allows it to live happily in a human home as a companion.

    Genetic Disorders

    • Extensive inbreeding has taken its toll on the domestic dog. By manipulating the physical appearance of the dog through selective breeding, certain genetic traits often occur. Bulldogs and pugs often have severe breathing problems because of their flattened faces. Breeding often passes down defective genes along with good genes. Genetic disorders such as cardiac problems, immune-system defects, skin conditions and neurological conditions exist in some dog breeds. More than 60 breeds suffer from genetic cataracts, according to PBS. Inherited orthopedic disorders, such as elbow and hip dysplasia, appear in many large dog breeds.