Fossil records show there are three main groups of dogs and they have been around for many years. Some have become extinct.

Group one came from North America around 40 million years ago. These dogs looked like a mix of a weasel and a fox from fossil evidence. They became extinct around 15 million years ago. They were called Hesperocyon, which means “western dog”.

Group two were larger and looked similar to hyena’s with big jaw muscles and strong teeth. They began around 34 million years ago and became extinct around 2.5 million years ago. They were called borophagines.

Group three called canines includes dogs we know today. This group is first seen in fossils from North America around 7 million years ago.

To acquire a smaller dog with increased agility and more stamina and fighting ability bulldog was bred with game hunting terriers. As this breeding increased so did aggression in these dogs.

Dog fighting breeders especially searched for dogs with gaming and aggressive behavior, as their goal was to refine best canine gladiator in bulldog.

Dog fighting was seen through out 1800’s into 1900’s and still does continue today. But, it is illegal in most of 50 states in America and most European Countries.

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