As a tabby cat is frequently a domestic shorthair cat, the question doesn’t make sense as it is trying to ask the difference between two types of domestic cat when the two descriptions often apply to the same individual cat as you see in the photograph below.
In fact, tabby is the most common domestic cat coat pattern and, likewise, the domestic shorthair is the most common domestic cat type. So, the two frequently go together.
The question comes about because of a misunderstanding of the word “tabby” and the phrase “domestic shorthair”. Tabby is a type of cat coat produced by the agouti gene. The original domestic cats were tabbies because the ancestor of the domestic cat is essentially a tabby cat namely the North African wildcat. You probably know that there are three types: the spotted tabby, the mackerel tabby and the blotched or classic tabby. The first two sometimes overlap. The last version of the tabby coat didn’t come into existence until quite recently through evolution whereas the mackerel tabby has been in existence for 10,000 years approximately.
So, the word “tabby” describes a cat coat and that coat can be on any domestic, stray or feral cat. The cat doesn’t have to be purebred, pedigree or a random bred moggy.
The majority of domestic cats are domestic shorthairs. The phrase applies to non-purebred domestic cats with a short coat. This is the most common type of domestic cat. It’s a general term which describes a random bred cat actually. It could, theoretically, apply to purebred cats as well because there are many breeds with shorthaired coats. But it doesn’t apply to purebred cats because it’s meant to be a general or generic term to describe second-class citizens in the domestic cat world of the cat fancy namely moggies! The cat fancy is a group of people who selectively breed and show cats.
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