Welcome to Brainstuff from house stuff works dot com, where smart happens him Marshall Brain with today's question, why do cats have whiskers? Whiskers are also known as tactle hairs, and they are long, thick, flexible hairs on a cat's face. These hairs are located in horizontal rows on the whisker pad, the puffy area between the top corners of the cat's mouth and the outer edges of his nose. Whiskers are like normal hair and that they fall out and do
get replaced. But whiskers are different from a cat's body hair in a few different ways. First, whiskers should never be cut or trimmed, and we'll see why later. Whiskers are two to three times thicker than a cat's hair. And finally, whiskers are rooted very deep in the cat's face in an area rich in nerves and blood vessels. In addition to having the long tactle hairs on their cheeks, cats also have shorter ones above their eyebrows, on their chin,
and on the back of their front legs. Since we're most familiar with facial whiskers, let's look at what they're good for. First. They're good for navigation, second, they're good for mood indication, and third they're good for measuring and opening. Whiskers help the cat feel his way around a room or an area. Whiskers are so sensitive that they can detect the slightest directional change in a breeze at night. For example, this helps a cat slink its way through
a room and not bump into anything. How it's because the air currents in the room change depending on where pieces of furniture are located. As the cat walks through the room and approaches a couch, he'll know which direction to turn based on the change in air current around the couch. In addition to having sensory properties, cat's whiskers are also a good indicator of his mood. When a cat is angry or feels defensive, the whiskers will be
pulled back. Otherwise, when a cat is happy or curious or content, the whiskers will be more relaxed and pushed forward. But the whiskers primary use is to help a cat judge whether or not he'll fit through an opening. A cat's whiskers are roughly as wide as his body, sort of like a natural ruler. The whisker tips are sensitive to pressure. You'll notice that a cat will stick his head in and out of an opening before he puts his body in. He's judging the width of that opening
and is determining if he can fit into it. An interesting note, cats don't have true collar bones like humans do. This allows them to turn and twist their way through very narrow openings compared to a human being. Be sure to check out our new video podcast, Stuff from the Future. Join How Staff Work staff as we explore the most promising and perplexing possibilities of tomorrow the house Stuff Works iPhone app has arrived. Download it today on iTunes.