1 00:00:00,520 --> 00:00:03,800 Speaker 1: Welcome to Brainstuff from house stuff works dot com, where 2 00:00:03,840 --> 00:00:15,520 Speaker 1: smart happens him Marshall Brain with today's question, why do 3 00:00:15,680 --> 00:00:20,840 Speaker 1: cats have whiskers? Whiskers are also known as tactle hairs, 4 00:00:21,000 --> 00:00:24,680 Speaker 1: and they are long, thick, flexible hairs on a cat's face. 5 00:00:25,360 --> 00:00:29,560 Speaker 1: These hairs are located in horizontal rows on the whisker pad, 6 00:00:30,080 --> 00:00:33,239 Speaker 1: the puffy area between the top corners of the cat's 7 00:00:33,280 --> 00:00:36,960 Speaker 1: mouth and the outer edges of his nose. Whiskers are 8 00:00:37,000 --> 00:00:39,559 Speaker 1: like normal hair and that they fall out and do 9 00:00:39,720 --> 00:00:43,520 Speaker 1: get replaced. But whiskers are different from a cat's body 10 00:00:43,600 --> 00:00:47,120 Speaker 1: hair in a few different ways. First, whiskers should never 11 00:00:47,200 --> 00:00:50,600 Speaker 1: be cut or trimmed, and we'll see why later. Whiskers 12 00:00:50,680 --> 00:00:53,480 Speaker 1: are two to three times thicker than a cat's hair. 13 00:00:54,040 --> 00:00:57,520 Speaker 1: And finally, whiskers are rooted very deep in the cat's 14 00:00:57,560 --> 00:01:01,120 Speaker 1: face in an area rich in nerves and blood vessels. 15 00:01:01,280 --> 00:01:05,040 Speaker 1: In addition to having the long tactle hairs on their cheeks, 16 00:01:05,520 --> 00:01:09,319 Speaker 1: cats also have shorter ones above their eyebrows, on their chin, 17 00:01:09,560 --> 00:01:12,399 Speaker 1: and on the back of their front legs. Since we're 18 00:01:12,440 --> 00:01:15,959 Speaker 1: most familiar with facial whiskers, let's look at what they're 19 00:01:16,000 --> 00:01:19,680 Speaker 1: good for. First. They're good for navigation, second, they're good 20 00:01:19,720 --> 00:01:23,600 Speaker 1: for mood indication, and third they're good for measuring and opening. 21 00:01:24,240 --> 00:01:27,680 Speaker 1: Whiskers help the cat feel his way around a room 22 00:01:27,840 --> 00:01:31,479 Speaker 1: or an area. Whiskers are so sensitive that they can 23 00:01:31,520 --> 00:01:35,400 Speaker 1: detect the slightest directional change in a breeze at night. 24 00:01:35,560 --> 00:01:38,560 Speaker 1: For example, this helps a cat slink its way through 25 00:01:38,600 --> 00:01:42,440 Speaker 1: a room and not bump into anything. How it's because 26 00:01:42,480 --> 00:01:45,560 Speaker 1: the air currents in the room change depending on where 27 00:01:45,640 --> 00:01:49,680 Speaker 1: pieces of furniture are located. As the cat walks through 28 00:01:49,680 --> 00:01:52,880 Speaker 1: the room and approaches a couch, he'll know which direction 29 00:01:52,960 --> 00:01:55,960 Speaker 1: to turn based on the change in air current around 30 00:01:56,040 --> 00:02:00,960 Speaker 1: the couch. In addition to having sensory properties, cat's whiskers 31 00:02:00,960 --> 00:02:04,080 Speaker 1: are also a good indicator of his mood. When a 32 00:02:04,120 --> 00:02:07,760 Speaker 1: cat is angry or feels defensive, the whiskers will be 33 00:02:08,000 --> 00:02:12,400 Speaker 1: pulled back. Otherwise, when a cat is happy or curious 34 00:02:12,480 --> 00:02:16,240 Speaker 1: or content, the whiskers will be more relaxed and pushed forward. 35 00:02:16,760 --> 00:02:19,760 Speaker 1: But the whiskers primary use is to help a cat 36 00:02:20,000 --> 00:02:23,600 Speaker 1: judge whether or not he'll fit through an opening. A 37 00:02:23,720 --> 00:02:27,239 Speaker 1: cat's whiskers are roughly as wide as his body, sort 38 00:02:27,280 --> 00:02:31,160 Speaker 1: of like a natural ruler. The whisker tips are sensitive 39 00:02:31,200 --> 00:02:34,080 Speaker 1: to pressure. You'll notice that a cat will stick his 40 00:02:34,160 --> 00:02:36,919 Speaker 1: head in and out of an opening before he puts 41 00:02:36,919 --> 00:02:40,519 Speaker 1: his body in. He's judging the width of that opening 42 00:02:40,800 --> 00:02:43,520 Speaker 1: and is determining if he can fit into it. An 43 00:02:43,560 --> 00:02:48,040 Speaker 1: interesting note, cats don't have true collar bones like humans do. 44 00:02:48,520 --> 00:02:51,320 Speaker 1: This allows them to turn and twist their way through 45 00:02:51,560 --> 00:02:56,679 Speaker 1: very narrow openings compared to a human being. Be sure 46 00:02:56,720 --> 00:02:59,640 Speaker 1: to check out our new video podcast, Stuff from the Future. 47 00:03:00,040 --> 00:03:02,280 Speaker 1: Join How Staff Work staff as we explore the most 48 00:03:02,280 --> 00:03:07,359 Speaker 1: promising and perplexing possibilities of tomorrow the house Stuff Works 49 00:03:07,400 --> 00:03:10,680 Speaker 1: iPhone app has arrived. Download it today on iTunes.