To most people, cats and dogs are cute animals. But what makes them so? Is it their appearance, behavior, or both?
Cats and Dogs have many physical features that humans often find charming. A big pair of eyes is the most famous example of these traits. Another trait is their soft fur, which adults usually want to touch and cuddle, and children want to hug.

The animals’ behavior also plays a role in their cuteness. Dogs are more likely than cats to approach humans or other animals on four legs, which makes them appear vulnerable and non-threatening.
They also lick people’s faces, which causes the humans to react in a positive way. Cats are less likely than dogs to approach strangers and do not lick their faces (except for cats that know and like their owners, but even then it is rare). These behaviors cause adults and children to feel maternal or paternal instincts toward the animals.
These physical and behavioral traits seem to trigger positive reactions in humans.
Sometimes they act clumsy by falling down or bumping against people accidentally, which can induce laughter in most humans.
People who do not like cats and dogs, however, may find some or all of these traits annoying. If the person has had a bad experience with one type of pet in particular, they will most likely be biased against other animals in this category.
For example, if a child falls while holding a cat and gets scratched by its claws, they will probably not want to play with cats anymore.

A dog may also seem unappealing if the owner finds it difficult to train, or finds that it smells bad. Like humans, animals are individuals and have different personalities so this trait should not always apply to other members of each species.
The point is that there are both appealing and unappealing qualities to both cats and dogs.
Cats and Dogs are not the only animals that humans find cute for these reasons, however. A species of monkey called the Cotton-top Tamarin also has many physical features that may be found endearing by humans.
For example, their eyes are surrounded by white fur instead of dark fur like other monkeys. The Tamarins also have very small ears and big noses, which makes them appear less threatening than other types of monkeys. Their tails are long compared to their bodies, making them seem childlike instead of adult-like.
They have short hair that covers most of their body, including the pads on their feet, unlike other types of monkeys.

Like the Tamarins, other animals are also seen as cute for their appearance and behavior. For example, koala bears have big eyes that are surrounded by white fur. They have round ears much bigger than those of cats or dogs, to accommodate their large eucalyptus leaves diet.
Some scientists think there is an evolutionary reason behind human beings’ perception of cuteness in dogs and cats. They believe our ancestors found those traits useful, as they wanted to keep those animals as pets to protect themselves against dangers.
As a result, we subconsciously perceive the features and behaviors that would have helped us survive many years ago as cute, even though they may not be useful anymore.