It was not until 1970 that The Kennel Club in the UK recognised the American Cocker Spaniel as being separate from the English type. American Bulldogs are typically confident, social, and active dogs that are at ease with their families. Bulldogs pictured as late as 1870 resemble contemporary American Staffordshire Terriers to a greater degree than present-day Bulldogs. Some dogs, such as the Löwchen, have an uncertain origin and are listed under several countries. Yet, although several programs are undergoing to promote pet adoption, less than a fifth of the owned dogs come from a shelter..
While there are unproven theories that other hairless dog breeds have common ancestry, the recent evolution of the American Hairless Terrier demonstrates an independent evolution from other hairless breeds. While the goal of the breed was originally to produce a working farm utility dog that could catch and hold wild boar and cattle, kill vermin, and guard an owner's property, when properly trained, exercised and socialized, this breed can become a great family pet. Its coat is short and generally smooth.
The color conformation is quite varied, but solid black or any degree of merle is considered a cosmetic fault, and a blue color is a disqualification by the NKC Breed Standard. It was not until 1970 that The Kennel Club in the UK recognised the American Cocker Spaniel as being separate from the English type. American Bulldogs are typically confident, social, and active dogs that are at ease with their families. Some dogs, such as the Löwchen, have an uncertain origin and are listed under several countries. Breeds listed here may be traditional breeds with long histories as registered breeds, rare breeds with their own registries, or new breeds that may still be under development. Centuries of selective breeding by humans has resulted in dogs being more genetically diverse than most other mammals by a considerable margin. However it has been disputed that "trying to achieve status" is characteristic of dog–human interactions. Pet dogs play an active role in family life; for example, a study of conversations in dog–human families showed how family members use the dog as a resource, talking to the dog, or talking through the dog, to mediate their interactions with each other. Another study of dogs' roles in families showed many dogs have set tasks or routines undertaken as family members, the most common of which was helping with the washing-up by licking the plates in the dishwasher, and bringing in the newspaper from the lawn. Increasingly, human family members are engaging in activities centered on the perceived needs and interests of the dog, or in which the dog is an integral partner, such as dog dancing and dog yoga. According to statistics published by the American Pet Products Manufacturers Association in the National Pet Owner Survey in 2009–2010, it is estimated there are 77.5 million people with pet dogs in the United States. The same survey shows nearly 40% of American households own at least one dog, of which 67% own just one dog, 25% two dogs and nearly 9% more than two dogs. Black pigmentation on the nose and eye rims is preferred, with only some pink allowed. In 2013, the cocker spaniel ranked 29th the American Kennel Club registration statistics of historical comparisons and notable trends.