Can cats really laugh?

Cats can't laugh. Although they have muscles to make smiling expressions, they don't express happiness through smiling expressions.

The cat's "laughter" is called the "cleft lip smell" reaction. In daily life, when a domestic cat smells a strong or strange smell, it usually has its mouth half open, its upper lip raised, its teeth exposed and its eyes narrowed, which seems to be smoked by a strong smell. This is called cleft lip sniffing.

For example, the root of the cat's maxillary incisors (the arched part in the mouth) has two tiny holes, which are connected with the vomeronasal device. The odor molecules absorbed here can reach the brain through a different path than the odor inhaled by the nose. In order to make the nose plow absorb odor molecules, it is necessary to half-open the mouth and raise the upper lip. Turning up the upper lip is beneficial to transfer the smell to the nose plough. With the nose plough, animals can better feel the smell and pheromones.

Animals with olfactory response to cleft lip include horses, cows, elephants, tigers, tapirs, lions, giraffes, goats, alpacas, koalas, hedgehogs, rhinoceroses and giant pandas.

For example, the rabbit's lip sniffs a lot, which attracts people's attention. Grinning, like laughing, is actually a kind of sexual behavior, which is considered to be done in order to be able to perceive the hormones contained in the urine of the opposite sex.