Why Do Cats Have Rough Tongues? The Science Explained

Have you ever wondered why your cat’s tongue feels like sandpaper? It’s because it’s covered with tiny, hook-like structures called papillae. These backward-facing spines have several purposes, vital for a cat’s wellbeing. We explore the science behind why cats have rough tongues and how it helps them every day, from grooming to eating and drinking.

The anatomy of a cat’s tongue

If you’ve ever been licked by a cat, you might be wondering why cats have such rough tongues. That sandpaper texture is caused by a dense carpet of hundreds of tiny, backward-facing hooks. These hooks, or papillae, are made of keratin, the same hard protein found in human fingernails. It’s this keratin that gives their tongues a rough texture. 

Papillae serve multiple purposes:

• Grooming: Papillae act like natural combs, efficiently removing loose fur and dirt from a cat’s coat. They help in spreading natural oils, ensuring that a cat’s fur remains shiny and healthy.
• Feeding: These spines aren’t just for grooming. In the wild, they help cats scrape every bit of meat off bones.
• Hydration: The papillae’s structure aids cats in drinking water too. They use their tongues to pull liquid upward into a column straight into their mouths.

Science explains why cats have rough tongues

In a 2018 research study, scientists from the Georgia Institute of Technology used high-speed videography, thermal cameras and CT scans of cat tongues to get a closer look at how papillae function and why cats have rough tongues. Here’s what they discovered:

• Flexible design: Cat papillae have the ability to rotate. This rotation enables them to penetrate and untangle knots in fur effectively.
• Hollow spines: Cat papillae have hollow channels that draw saliva deep into the fur. This method allows cats to clean themselves effectively while also helping to keep cool through evaporation.

Taking inspiration from nature’s incredible design they used the knowledge they gained about a cat’s tongue to develop a better grooming brush which could also be used to treat skin allergies by applying medications directly to a cat’s skin. 

Purpose and function of cat tongues

Let’s explore the critical role of a cat’s tongue in day-to-day life and how it assists them to groom, eat and even regulate temperature. 

Grooming

The tongue’s rough texture, thanks to those tiny hooks called papillae, acts like a natural hairbrush and allows your feline friend to comb through their fur. These structures efficiently remove loose hair, dirt and even parasites trapped in the coat. Ever notice how sleek a cat’s fur looks after grooming? That’s because these papillae also help distribute natural oils across the fur, maintaining a healthy, shiny coat. With every lick, cats smooth out their fur, reducing the likelihood of mats and tangles. 

In the 2018 research study mentioned above, scientists also worked out how the far the papillae penetrate into fur when grooming. By comparing this with the average fur length in different breeds, they determined that the only cats that can’t groom themselves effectively are long-haired Persians. So, if you own a Persian cat, make sure you find time to brush them regularly.  

Temperature regulation

Grooming does more than just keep cats clean; it plays a role in temperature regulation too. As cats groom themselves, their saliva evaporates off their fur, offering a cooling effect much like our sweat. This is particularly useful for cats living in warmer climates. 

Eating meat or prey

In the wild, every scrap of meat counts. As obligate carnivores, cats’ tongues have evolved to help them get the most out of their meals. When your cat is eating, those rough papillae on their tongues act like a natural scraper, allowing cat’s to efficiently remove flesh from bones. Although pet cats don’t face the same survival challenges as their wild ancestors, this inherited trait aligns with their natural hunting instincts. Even when eating kibble, their tongue helps manoeuvre food around the mouth and assists in swallowing.

How cats use their tongue to drink

You might think cats drink water like most other animals, but their technique is quite unique. Cats have mastered the art of drinking with quick, efficient motions that might seem simple but are actually quite complex.

Unlike dogs, which scoop water with their tongues, cats extend their tongues and lightly touch the tip against the water’s surface. Then comes the magic. With a rapid flicking motion, cats create a column of water that seems to defy gravity for a split second. This isn’t just a splash – it’s a carefully timed lift. The cat’s tongue moves in and out at just the right speed (about four times per second) to keep the water in a neat column. It’s a balancing act between inertia and gravity, ensuring not a drop goes to waste.

This technique is so precise that even wild cats like lions and tigers use it, although at a slower pace due to their larger size. High-speed videos show this method allows cats to drink efficiently without getting their faces wet. It’s all about timing and control, with each lap designed to optimise their water intake. Next time you see a cat having a drink, take a moment to appreciate the skill behind what looks like a simple act.

Signs of a healthy cat tongue

A cat’s tongue can tell you a lot about their overall health. A healthy cat tongue is usually a vibrant pink, and relatively dry. If you notice their tongue looks a bit off, it could be a sign of an underlying health issue. 

Here are the key signs to watch for:

• Colour changes: A healthy tongue is usually a vibrant pink. Any changes to pale pink, white, or even blue can be a warning sign, so it’s a good idea to consult with your vet.
• Texture: While the papillae give the tongue a rough feel, it shouldn’t have cuts or sores.
• Dryness and salivation: Excessive drooling or a constantly wet tongue can be signs of health problems.

Final thoughts

Cats’ rough tongues are a handy tool, essential for their everyday needs and wellbeing. From grooming their fur and keeping cool to eating a meal, those tiny spines, known as papillae, serve many purposes. 

Their tongues also allow them to drink with precision. Instead of splashing about like dogs, they create a neat water column that quenches their thirst. Their tongue’s unique design is surprisingly efficient, highlighting just how well nature’s designs can work.

Next time your cat licks you, take a moment to appreciate their unique biology. A cat’s rough tongue is a reminder of their wild ancestry, offering a glimpse into the clever ways cats have evolved to thrive in their natural environments.