We feed them, play with them, and snuggle them every day. But how well do we really know our pets?

There’s no denying it: We pawsitively love our pets—especially our cats and dogs. More than half of all American families own at least one dog or cat. That adds up to 83 million pet dogs and 95 million pet cats!

If you have pets, you have probably noticed some curious things about how they eat, sleep, play, and live their lives. Here are answers to some questions about why dogs and cats do what they do—starting with why they don’t seem to love each other as much as we love them!

Do cats and dogs really not get along?
You’ve probably heard the saying, “They fight like cats and dogs.” And cats and dogs do fight sometimes. A dog may view a cat as prey. Or it may want to chase the cat as a way of playing with it. Either way, the cat will likely view the dog as a threat–and may react with a claws-out swipe to Fido’s nose.

But some cats and dogs get along just fine. Usually, if a cat and a dog are raised together from the time they’re young, they will live in peace under the same roof—and may even become pals.

Why does my dog drool so much?
First of all, drool is saliva—same wet stuff you have in your mouth. It helps dogs—people—and digest food. And just like people, dogs may make more saliva when they are about to eat. (Think of what happens to you when you look at a mouthwatering slice of pizza!)

Some types of dog are more likely to drool than others because of how their heads are shaped. Dogs with short snouts, such as bulldogs, often drool more because their mouths are too small to hold all their saliva. And “jowly” dogs, such as basset hounds, drool because the loose skin around their mouths lets the saliva seep out.

Why does my cat puff up when she sees a dog?
When your cat’s fur stands on end, it makes her look bigger. She may also hunch her back and turn sideways, which makes her look even BIGGER. That’s her way of saying, “I’m too big to mess with!” It’s a smart move, too. If she ran away instead, the dog would almost certainly chase her. And that could be a cat-astrophe!

Why do dogs sniff each other’s rear ends?
A dog can’t introduce itself with a handshake and a “hello.” Instead, it greets other dogs in a way that’s just right for an animal with a super sense of smell. Each dog has glands near its tail that give off different smells. Those smells may tell other dogs whether it is male or female, young or old, weak or strong. So a quick sniff to the tail of an unfamiliar dog gives the sniffer a bunch of useful information. And while it may seem rude to you, the sniffee usually doesn’t mind a bit.

Why does my cat go outside for just a minute, then turn around and want to come right back in?
Cats like to keep an eye on their territories—especially if there are other cats around. They don’t need to spend a lot of time on “patrol,” but they like to do it often. So your cat is probably going outside to make sure no one is invading its territory there—then coming back inside to do the same.

But remember: Cats can hurt birds and other small animals when they are allowed outside. And they can get hurt by cars or by larger animals. So it’s best to keep your cat inside, anyway. Then you won’t have to keep ­letting it in and out!

Why does my dog scratch his bed and turn around before he goes to sleep?
Scientists don’t know for sure. But some believe that dogs picked up this habit from their wild ancestors: wolves. A wolf wouldn’t have its own padded, cozy bed to lie on. So it would make one for itself by turning around a few times and scratching up leaves, dirt, and branches. This would make a looser, softer place to snooze.

Why does my cat hang out inside cardboard boxes and paper bags?
Cats like the support that small spaces offer. They also feel safer when they can see any coming threats—such as a dog or a tail-pulling toddler—retreat to a hiding spot. Some cats also like to play while hidden. They may wait quietly until someone walks by, and then—swipe!—out comes a paw to grab a shoelace or an ankle.

Do my cats meow at each other when I’m not around?
Cats may hiss, growl, or purr at each other. But meowing is something adult cats do only when people are around. Kittens do meow at their moms–it’s how they ask for milk or attention. So when they grow up, they turn their meows on the people who fill their food bowls and offer ear scratches.