But unless you're deathly allergic, they're also largely harmless, unless you freak them out and they get their claws into you.

But, as all cat lovers know, sometimes our otherwise friendly felines will bite us when we're trying to pet them, which makes no sense at all.

Why get all bitey with the human who loves them, feeds them, and passive-aggressively scoops their litter box?

Some cat owners call these weird forays into ferocity "love bites," but vets know better and call the behavior: "petting-induced aggression."

Petting-induced aggression differs from flat-out unfriendly behavior; some cats just don't like to be petted at all, period, and will take a swipe at you if you try.

But that's not the behavior we're exploring here.

A cat who exhibits petting-induced aggression will seek affection, submit to it, and then inexplicably start nibbling on you like you're made out of Meow Mix.

What gives?

Why the sudden revolt?

According to the experts over at VetStreet, there are a few theories about why cats might do this.

First of all, the ancestor of the modern house cat was probably a solitary animal, so the whole social hierarchy thing is still pretty new to her.

Your cat may reach a point during that moment of shared affection where she thinks, "I can't let this person think I'm actually domesticated or anything, I'd better just bite them."

That might not explain all petting-induced aggression, though.

Another theory is that some cats might actually experience prolonged petting negatively, and the biting is a reaction to that.

It could be that petting actually starts to feel physically irritating to the cat when it's overdone.

So maybe it literally just rubs the cat the wrong way.

Biting could also happen when a cat gets excited and decides the petting session should turn into playtime.

Cats are predators, after all, and they hone their hunting skills by batting Legos around on the floor, ambushing your ankles when you're on your way to the bathroom late at night.

And possibly by biting you when you're trying to show affection.

So if your particular brand of petting leans a little on the aggressive side, your cat could just be responding to that in a totally natural way.

One final theory is that the sudden switch between enjoying the moment and thirsting for blood might actually be communicated, but in a subtle way.

"A cat's eye reveals everything."

"What's that supposed to mean?"

There could be small cues that the cat is no longer enjoying the interaction, but they may be so slight that some owners just don't notice them until it's too late.

So what should a cat owner do with a furry friend who suffers from petting-induced aggression?

Well, no one is saying these cats are a lost cause, it's really just a matter of learning how to tune in to the animal's mood so you can predict when a petting session might turn into a bloodbath.

That could mean just taking note of how long your cat will usually tolerate petting before sinking their teeth into you, and then making sure you always stop well in advance of that.

Or look for cues, like a flicking tail or flat ears.

Bottom line: If you're at the end of your rope over your cat's constant chomping, consult a veterinarian.

A professional can help you figure out how to better read your kitty's cues and keep the human-nibbling to a minimum.

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