Bull and terrier

Bull and terrier was a common name for crossbreeds between bulldogs and terriers in the early 1800s. Other names included half-and-halfs and half-breds. It was a time in history when, for thousands of years, dogs were classified by use or function, unlike the modern pets of today that were bred to be conformation show dogs and family pets. Bull and terrier crosses were originally bred to function as fighting dogs for bull- and bear-baiting, and other popular blood sports during the Victorian era. The sport of bull baiting required a dog with attributes such as tenacity and courage, a wide frame with heavy bone, and a muscular, protruding jaw. By crossing bulldogs with various terriers from Ireland and Great Britain, breeders introduced "gameness and agility" into the hybrid mix.

Little is known about the pedigrees of bull and terrier crosses, or any other crosses that originated during that time. The types and styles of dogs varied geographically depending on individual preferences. Breeders in one area may have preferred a cross with a higher percentage of terrier than bulldog. Some early anecdotal reports indicate that bulldog to terrier was preferred over bull and terrier to bull terrier, which was likely to have resulted in at least half or more bulldog blood. The bull and terrier was never a bona fide breed; rather, it referred to a heterogeneous group of dogs that may include purebreds involving different breeds, as well as dogs believed to be crosses of those breeds. Those crossbreeds or hybrids are considered the forerunner of several modern standardised breeds.

In the mid-1830s, when enforcement of the ban on bull baiting had begun, the popularity of the original purebred bulldogs declined, and a major shift in canine genetics was occurring. The appearance of certain dogs were being altered by crossbreeding to better suit function. Not only were appearances of dogs changing, so was the terminology used to describe various breeds and dog types as recorded in ancient records. Such changes began casting doubts over the bulldog's earliest known ancestors.

One example of how changing terminology over the centuries has caused confusion is the ubiquitous misuse of descriptors. For example, mastiff is a common descriptor for all large dogs, which created a cloud over the earliest origins of the bulldog. The Alaunt was once believed to be the likely ancestor of bulldogs and mastiffs, both of which came from Asia; others believed bulldogs descended only from mastiffs.

Over the centuries, hybrid bull and terrier crosses have been labelled with several aliases, such as half-and-half, half-bred, pit dog, bulldog terrier and pit bulldog. The most popular name was bull-terrier, a name later applied to the breed James Hinks was developing in the latter half of the 19th century. There are also many paintings, texts, and engravings created during or prior to this period that labelled the bull-and-terrier only as "bull-terrier". Hinks was still developing his new bull terrier, nicknamed White Cavalier, which he presented at the Birmingham show in May 1862.

The term pit bull terrier was sometimes applied, though later applied when naming the American Pit Bull Terrier, a modern standardised breed. The term "pit bull" is a ubiquitous term that is often misused to infer that the pit bull is a bona fide breed of dog, when it actually refers to a diverse group of dogs that may include purebred dogs of many breeds as well as dogs that are assumed to be blends of those breeds. These types of descriptors vary, depending on the recognised breeds and observers' perspectives. Despite anecdotal misinformation and incorrect visual identification, dog owners, animal shelters, veterinarians and the general public routinely use the term "pit bull" in casual and official papers as though it denotes a single, recognised breed.

Bulldogs of the 1800s were described as having a "round head, short nose, small ears and wide, muscular frame and legs." Their temperament has been described as being more aggressive and ferocious than other dogs of the time. It is believed their ancestors may have been mastiffs of Asian descent because of their aggressive tendencies and strength, but the term "mastiff" was used as a general reference for large dogs. Whether or not they were crossed with Pugs to make them better at bull baiting remains controversial.

It is assumed that bull and terrier hybrids were crossed with several varieties of bulldogs and terriers, the types of which depended on location. A 2016 genetic assessment verified that bulldogs were descendants of mastiffs, but it also discovered pugs in the cross. The assessment, which analysed a particular group of individual English bulldogs, used DNA rather than pedigrees to confirm that genetic diversity actually still exists. It further confirmed a substantial loss of genetic diversity in the breed resulting from a small founder population of about 68 individuals. The impact of focused selection for breeding dogs with specific physical traits created artificial genetic bottlenecks.