You may have noticed that, after a cat smells something, it keeps its mouth open for a while. This is called the flehmen response and cats do it in order to analyze what they’ve been smelling.
According to kitten rescuer Hannah Shaw, this is “a cat’s way of analyzing an unfamiliar and interesting scent. The flehmen response allows the scent to travel to the vomeronasal organ on the roof of the mouth,” Shaw wrote on Instagram.
Cats smell stuff with their nose and mouth and the sensory information they get actually falls between smell and taste. The flehmen response is not only common in domestic cats; big cats like tigers and lions also show this behavior.
Female cats use this method to know where their kittens are, while males mostly use it for mating purposes, as veterinarian Sasha Gibbons told Catster. “Scents can help indicate compatibility and if the timing is right,” Gibbons said.