5 Crazy Cat Anatomy Facts

• a Care2 favorite by Samantha, selected from  Animal Planet

Curiosity about cats has followed humankind since the days before  Egyptian pharaohs treasured them  as signs of good fortune. Much more is  known today about what makes these  graceful critters tick, yet we’re  still mesmerized by a cat’s nighttime eyes  and find comfort in the  mysterious vibration of a gentle purr. Taken  individually, the bits and  pieces of cat anatomy and behavior are a crazy quilt  of Morse code, text  messaging and DIY survival tips. Together, they’re a medley  of fun  facts that add up to a fur-covered package of intrigue. Let’s look at   five unusual cat anatomy facts.

5. Eyes That Glow in the Dark

Green, gold, blue or yellow, cats’ eyes are  fascinating orbs that gleam in  darkness. Think of the famous Cheshire  cat, whose eyes and grin taunted  Alice in  Wonderland. Use a flashlight  beam to observe your cat in a darkened  room. That spooky shine is  visible even in dim light.

Cats’ eyes have pupils that are larger than humans’, and are  controlled by a  pair of shutter-like ciliary muscles, creating the cat’s  distinctive slit-like  pupil in bright light. In darkness, light hitting  feline eyes is reflected from  a mirror-like membrane behind the retina.  This structure is called the tapetum  lucidum, and is present in the  eyes of cats, dogs, some fish and birds, and  other nocturnal hunting  animals.

When light enters a cat’s eyes, it goes through the retina, where   light-sensor cells, called rods and cones, absorb it. Any unabsorbed  light  reaches the tapetum lucidum and bounces back to the retina,  enabling it to take  in more light.  Animals with the tapetum lucidum have greater night vision  because it  lets them absorb more light. This is a great help when looking for  prey  at night. Cats need only about one-sixth of the light humans need to   function in the dark.

4. The Rough Side of the Tongue

If you’ve received a loving lick from your cat,  you know that sweet pink  tongue feels like rough-grade sandpaper or  Velcro caressing your skin. And a  jungle cat’s tongue is even harsher.  All feline tongues, from tabby house pets  to 600-pound (272 kilogram)  Bengal tigers, are covered with tiny barbs or  hooks, giving the tongue a  rough texture. These microscopic projections face  toward the cat’s  throat, and are the tools that help to groom his coat. The  barbs work  like a comb, catching and cleaning the cat’s fur. In the wild, these  rasps tear the flesh off the bones of the big cat’s prey.

Cats’ tongues may be the busiest part of their anatomy. They lick  their  coats not only to  keep clean, but to regulate their body  temperatures, fluffing up the fur in  winter and wetting it down with  saliva to stay cool in summer.

As cats’ tongues work, they collect flakes of skin, loose fur, fleas  and  dirt. Cats swallow this debris — which is usually dissolved by  stomach acid. Some cats, especially  long-haired or older ones, may  ingest too much hair to dissolve, and upchuck  hairballs. Giving your cat  hairball ointment will help him digest the hair he or she  swallows.

3. Tale of the Tail

A cat’s tail, which contains almost 10 percent  of his bones, acts as a  counterweight in helping him keep his balance  while walking along a narrow  space or making sudden turns. But besides  working as a rudder, a cat’s tail  communicates his mood and messages.  Decoding tail talk is one of the easiest  ways to read feline body  language.

A relaxed cat’s tail moves gently, occasionally, side to side,  signaling  that he’s up for a little attention. With his tail held high  and straight, a  cat says he’s in charge and happy. If the tip quivers  slightly, the cat is  irritated.  A quick lashing motion, sometimes  accompanied by flattened ears, is  a sign that your cat wants to be left  alone, and may attack if you continue petting him. When  a cat is at play  or watching birds out a window, his crouched posture, with the  tail  flicking back and forth, mimics the behavior of a big cat stalking its   prey.  If a cat’s tail is straight up and bristled, he’s alert and ready  to  attack. A fluffed out, lowered tail signals fear. And a tail lightly  brushing  or wrapping around your legs spells affection and approval.

2. Purr-fection

The thrumming, rumbling sound coming from a cat  as she inhales and exhales  is one of life’s great delights — and  mysteries. Theories about purring are as  varied as the markings on a  calico. Domestic cats purr when they’re content,  often when we’re  stroking their chins or heads, or opening a can of food.  Mother cats  purr so their helpless newborn kittens can find them (and the  source of  dinner), and often purr while nursing. But cats also purr in times of  stress — when  they’re recovering from an injury, or at the vet’s  office. Some cats purr so loudly during a checkup, the vet can’t clearly  hear  the cat’s heartbeat through his stethoscope.

Scientists say that a cat’s purr results from intermittent signaling  by the  diaphragmatic (diaphragm) and laryngeal (larynx or voice box)  muscles, at a  frequency of 25 to 150 Hertz (a Hertz being one cycle per  second).  Research  suggests that sound frequency of this range can promote healing and bone growth. There’s no definitive  answer yet, and the power of the  purr is still a puzzle. Clinically, we may  know how cats purr, but why?  They may purr simply because…they can.

1. Whisker Communication

A cat’s whiskers are like a radar guidance  system, with a bundle of nerve  endings telegraphing details about  everything the cat touches, as well as  shifts in air pressure. His  whiskers are the same width as his body, letting  him know whether he’ll  be able to get through a narrow opening or fit behind  the TV set.

But whiskers are also navigators. These bristly hairs, found above  his  eyelids, around his muzzle and on the lower, inside part of his  forelegs, help  cats move smoothly in darkness. Sensitive to changes in  the air current around an unknown object,  whiskers enable the cat to  avoid the obstacle.

A hunting cat uses its whiskers to zero in on the outline of its  prey,  letting it know where to strike.  Damaged whiskers hamper its aim.  A cat’s  facial whiskers are also mood indicators. Stiff,  forward-pointing whiskers mean  the cat is aggressive.  An angry cat’s  whiskers are tightly pulled back against  its face. And a contented cat’s  whiskers are picture-perfect, forward, with a  slightly downward angle.