There are only 42 recognized cat breeds in the U.S., compared with 192 dog breeds. Still, why are cat breeds so similar-looking compared to dog breeds? (Think Chihuahua versus beagle versus German shepherd.)
One reason is that most of the selection that has produced today’s breeds of cats has taken place over the last 75 to 80 years, while dogs have been bred by humans for hundreds of years. That time span has allowed for more variation to develop. In addition, as people realized that dogs could perform highly specialized tasks, they worked very assiduously to mate dogs who would produce offspring especially good at those tasks. That’s why a dog bred to guard property or help with farm chores like herding is going to end up much different physically than a dog bred to burrow into tight underground spaces to catch varmints.
Cats don’t do many different kinds of tasks. They have typically held only two roles in our lives: as companions and as pest controllers. And they have always performed those roles perfectly well in their natural size and shape — there has been no need for manipulation to make them better at those jobs.
As some might put it, cats are born just right. Their mating doesn’t need outside interference.