If you are one of the third of people who own a pet cat – or one of the even higher number of people worldwide who admire these furry felines – this info is for you.

Did you ever find yourself looking lovingly at your cat and wondering… what is the deal with that fold of skin behind her ear?

Well, this little known fold is common among cats, as well as other beloved animals including dogs.

The name for this curious part of your cat’s anatomy?

Henry’s Pocket.

A recent article from IFLScience unpacked some theories around Henry’s Pocket, including speculation around the evolutionary purpose of this little pouch.

If you’ve spent time with cats, you’ll know just how flexible their ears are, bending left and right when they pick up noises to allow them to hear better.

When you’re petting a cat, you’ll notice too that they can flatten their ears completely against their heads.

This is because their ears have 32 muscles in them.

It’s thought that Henry’s Pocket helps cats keep their ears extra flexible, so that they can be even more receptive to auditory input.

This is particularly impressive due to the already incredible nature of cats’ ears.

It’s possible that Henry’s Pocket is the cherry on top of the cake, an extra specialised piece of hearing equipment that allows cats to detect an even bigger range of sounds.

Cats, it turns out, are incredible listeners.

They can hear sound waves with a much higher range than most other mammals – meaning that your cat can hear much ebtter than you can.

It is possible that Henry’s Pocket increases their ability to hear, by helping them tune in to lower pitched sounds.

Though many a cat owner will have countless stories about calling their cat’s name to no avail, they also have plenty of tales of the cat suddenly materialising as soon as the box of biscuits rattles or a tin of pet food dings open.

Cats may have incredible hearing, but they are smart enough to hear selectively, too.

With a current lack of scientific consensus, it is hard to say for sure what exactly Henry’s Pocket is for.

The article goes on to consider that – while extremely cute – the little flap of extra skin may have no purpose at all.

Whether it allows for extra sensory abilities, or is just a relic of the cat species’ past, there is one thing that is undeniable about Henry’s Pocket: it is adorable.

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