Cats look mostly alike in comparison to dogs. Although each feline has a unique face, the degree of variance is considerably higher in dogs.
This is mainly due to breeding. Dogs can vary between 8-80 lbs, depending upon breed - some will fit in handbags, others will barely fit into a car. Cats, on the other hand, have significantly less variation (between 8-25 lbs[1]).
Further complicating the problem is that we have bred some dogs specifically for facial features and shapes. An English Bulldog, for example, has a drastically different face than a Labrador.
However, the vast majority of cat breeds retain the same facial features and shape. Those that do vary (e.g, Siamese cats) differ by small amounts in comparison to dog breeds.
This is why building a "dog or cat" detector is reasonably straightforward (if it's not a cat, it must be a dog), but building a "dog, cat, or other" detector is far more complex.
you're talking about features important for human model of cognition. No arguing here - for most of the people, using the features you described (and for AI systems built by humans and using the same features), the cats would look more alike than dogs.
>However, the vast majority of cat breeds retain the same facial features and shape.
i had cats for many years and with time learned to see the difference, and i'm sure that some people like judges from cat shows would see even more distinction.
It is all about model of perception (and we naturally think and talk like our, human, model is the [only] model) and how well it is trained.
This is mainly due to breeding. Dogs can vary between 8-80 lbs, depending upon breed - some will fit in handbags, others will barely fit into a car. Cats, on the other hand, have significantly less variation (between 8-25 lbs[1]).
Further complicating the problem is that we have bred some dogs specifically for facial features and shapes. An English Bulldog, for example, has a drastically different face than a Labrador.
However, the vast majority of cat breeds retain the same facial features and shape. Those that do vary (e.g, Siamese cats) differ by small amounts in comparison to dog breeds.
This is why building a "dog or cat" detector is reasonably straightforward (if it's not a cat, it must be a dog), but building a "dog, cat, or other" detector is far more complex.
[1]:http://www.petobesityprevention.com/ideal-weight-ranges/