Sorry, dogs. Cats rule, but not by much. There are about 74 million pet cats in the U.S. and 70 million pet dogs. Cats live about 14 to 16 years, so plan on taking care of them for a long time. Having a cat may be good for your health. One study found people who have cats are 40% less likely to have deadly heart problems than people without cats.

Just like people, cats can be lefties or righties.  Researchers watched cats reach for food. Of more than 100 cats, about half reached with their right paw. About 40% used their left, and 10% used both their left and their right.

Cats don't chat when they meow. But purring, hissing, and shrieking may be part of how they get messages across. They also use body language and mark things with their scent. They mark things by rubbing them with their tail or face or by spraying them. They even scratch wood sometimes to show they were there!

Just like chocolate is really bad for dogs, it also can be toxic for cats. Too much of it can raise your cat's heart rate and blood pressure and cause seizures. Stick with kitty food treats instead.

A cat's collarbones are free-floating, so their heads are usually the widest part of their bodies. If your cat's head can fit through a tight space, generally, the rest of his body can follow. Cats also have loose skin, which gives them even more flexibility. 

Whiskers  are much thicker than normal hairs and are surrounded by nerves that help sense nearby objects. Whiskers also may show your cat's mood. They point forward when she's feeling friendly. They lie flat on her face when she's feeling threatened or aggressive.

Cats in their prime usually can jump about 5 feet off the ground. But, like people, they lose a bit of their spring as they get older. When arthritis sets in 75% of cats simply won't jump. Most of those who still spring up can't  jump as high. Medicine, supplements, and losing weight can ease your kitty's arthritis pain.

All kittens are born with blue eyes, and their eyelids stay closed until they are 10 to 14 days old. They usually get their true eye color by eight weeks.

The third eyelid is the pink tissue at the inner corner of a cat's eye. It helps protect the eye and spread tears over it. These extra eyelids usually stay hidden unless a cat is sleepy. Sometimes you see them in sick cats.

They don't call them cat naps for nothing. Cats sleep whenever they can, adding up to about 12 to 16 hours a day. Like people, cats probably have three different phases: awake, rapid eye movement (REM) sleep, and non-REM sleep. It’s normal to see your cat's face and leg muscles twitch when he sleeps. It's called "dream chasing."

Cats sweat, but not a lot. They have fewer sweat glands than people and sweat much less. The little they do sweat is often masked by their thick fur, although you may notice sweaty paw prints. They stay cool by grooming themselves. When they lick their hair, the saliva evaporates from their skin and cools them off.

Cats are pregnant for only about nine weeks, and they can get pregnant again just a few weeks after weaning their kittens. If you don't spay your cat, she could have many litters  in a year. This is really true in mild climates. Cats need at least 10 hours of light a day to be fertile.