When parents arrive at a daycare at the end of the day, their human toddlers often race into their arms while joyfully screaming, “Mommy!” or “Daddy!” That’s how parents know their kids recognize them.

Cats, on the other hand, can be much harder to read. Do they really know the difference between you and your neighbor?

Do Cats Recognize Their Owners?

For many cat owners, the answer to this question is a big fat “duh! Of course, my cat knows me!”

For example, when Brette McWhorter Sember comes home, her cat named Puffy meows loudly. However, when strangers walk into the house, her cat hides. Puffy also treats Sember differently than her husband.

“He sticks close to me all day, and if he gets separated from me, he calls out to find out where I am,” Sember says. “He knows my entire routine and is always waiting for the next thing. He doesn’t do any of this with my husband.”

Other cat owners share similar stories. They mention that a cat only offers gifts to one family member — and not others. Or, they’ll tell you their cat waits at the door for their return. Their cat might welcome them with loud purrs and excited floor rolls. However, if an unfamiliar person enters, the same cat will coldly walk away, hide, or even hiss loud disapproval.

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Can Science Prove Cats Know Their Owners?

Science, however, has taken many years to catch up to what many cat owners have long suspected.

“We can’t ask cats directly whether they recognize or remember us, so we have to infer the answer from their physiology and behavior,” says Mikel Delgado, a certified applied animal behaviorist and owner of Feline Minds, a cat consulting company in Northern California.

Over the years, scientists have designed thoughtful experiments to test these inferences. In one study, researchers watched how cats reacted to hearing their owner versus a stranger call their name. Most of the cats responded more intensely to their owner’s voice.

In another study, researchers played recordings of owners and strangers saying things like, “Do you want to play?” and, “How are you?” When strangers uttered the same sentences, cats didn’t respond. However, the cats became alert at the sound of their owner’s voice. They stopped whatever they were doing and moved toward the sound.

According to these experiments, cats do seem to remember the unique pitch, timbre, and volume of their owner’s voice.

Read More: Why Do Cats Love Boxes So Much?

How Do Cats Know You’re Their Owner?

(Original) However, cats likely use other clues as well. For example, your cat probably knows your unique physical form (size and shape) — and how it differs from your spouse’s, child’s, or any given stranger’s.

***Your cat probably knows your unique physical form (size and shape) — and how it differs from your spouse’s, child’s, or any given stranger’s.

“Your unique scent also plays a role,” says Delgado.

Thanks to an incredible sense of smell, your cat likely knows the difference between you and other humans who live in the same house — and especially between you and your neighbor from down the street. Cats can even tell if their feline housemates have been to the vet — because their aroma will have changed.

This entire package — the sound of your voice, the odor of your body, and your appearance — helps your cat to sort “Yay! That person who feeds me has returned!” from “Who the heck is that?! Time to scram!”

Read More: How Cats Purr: Understanding Those Adorable, Vibrating Noises

Do Cats Treat People Differently?

You may wonder: What if your cat loves everyone? Maybe they greet every single two-legged creature with loud purrs and head bunts. Does that mean your cat can’t differentiate between you and other humans?

Not necessarily, says Delgado.

It’s more likely that your cat is amiable and curious. You or someone else probably did a fantastic job socializing your cat during your cat’s first two to seven weeks of life.

If you’re still not sure if your cat knows you, it’s worth trying to see things from another perspective.

“People worry too much about what their cat thinks about them,” says Delgado. “Instead, they should be worrying more about whether they are providing their cat with a healthy environment that allows them to express natural behaviors like climbing, scratching, hiding, resting, and eliminating. Give your cat mental stimulation. Play with them and handle them respectfully. That way, you’ll have a great relationship with your cat even if they are straight out of the movie Memento.”

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