Despite the litter box stench, messy pâté dinner, and relentless suburban exploration, cats are among the most hygienic domestic species. The average cat dedicates over five hours a day to self-grooming and maintaining a visibly pristine coat. Cats are surprisingly self-sufficient with an unbreakable “lone wolf” aura, but why do cats clean each other and then sometimes fight?
Cats clean each other to assert dominance and release underlying aggression (the alpha cat does most of the giving). Others adopt a matriarchal role and use grooming to send protective and affectionate notions. Many cats are receptive to these makeshift baths and willingly purr and cooperate.
Just when you thought that “Aww Meter” couldn’t read any higher, you witness a heartwarming allogrooming session between two of your kitties. You want to believe it’s affection and decency that’s triggering this special treat. To learn about why (and how) cats clean each other, read on!
How Do Cats Clean Each Other?
There’s no doubt that cats are sanitary critters. On the quest for a well-groomed coat, sanitized wounds, and grime-free skin, cats will:
- Lick their coats clean in small patches (removing any evidence of their “scent,” loosening dirt, and keeping their hair lubricated)
- Chew or nibble at knots for a noticeably smoother texture
- Lick their paws for a quick face wash (cleansing the ears, eyes, and forehead in the process)
- “File” down their nails with aggressive chewing (all they’re doing is removing that sharp, outer sheath)
In the case of a feral cat looking to stay warm, pest-free, and “hidden” from predators, grooming becomes more of a survival instinct. Therefore, self-grooming is far more in-depth and intentional than those adorable allogrooming sessions.
Most helpful cats confine their grooming to another kitty’s neck, head, forehead, and ears. Cats who appreciate this impromptu bath may even bare their necks further or tilt their heads for better access and more thorough cleansing.
What Does the Research Say About Allogrooming?
We might not know why cats get the “zoomies” after pooping or prefer cardboard boxes to memory-foam (though, we can guess), but allogrooming happens to be relatively well-studied.
In a 1998 piece entitled “The Function of Allogrooming in Domestic Cats (Felis silvestris cams),” researchers learned about the why, when, and how behind kitties cleaning one another.
Here’s what the data revealed:
- Only 8% of these group cleaning sessions are “mutual” (it’s not a “You get my back, and I’ll get your” type scenario).
- Of all allogrooming sessions, about 12% will end in a scuffle.
- The more submissive of the pair acts as the “groomer” only 25% of the time.
- Nearly 47% of groomers — the “alpha” cat — sit upright as they lend a helping paw.
- In male-female duos, the male takes the lead grooming role more than 65% of the time.
- When allogrooming takes a more violent turn, the groomer instigates 7 in 10 fights.
Only 6% of these “baths” stray from the head and neck regions, and a baffling 94% stem from one cat approaching the other. Intriguingly, these results remained consistent despite kinship (siblings, parent/child duo, or unrelated) and whether a cat was fixed or not.
Why Cats Groom One Another
You envision peace, harmony, and joy as your cats take on that perceived caretaker role and selflessly clean one another mid-cuddle. But don’t let the rumbling purrs and seeping drowsiness take you as a fool — allogrooming doesn’t always signal generosity.
The three most common explanations for cats cleaning one another are:
Lending a Friendly Helping Hand
Cats have ultra-flexible spinal cartilage that allows for an impressive 180° rotation. This remarkable elasticity will enable cats to contort into funky sleeping positions, sneak through tight holes in the fence, and narrowly escape predators in the wild.
But overweight, arthritic, and elderly cats may gradually lose this flexibility where it matters most — grooming. Even young, agile kitties have trouble reaching:
- The belly
- The hind legs
- The base of the tail
- Between the shoulder blades
- The top of the head
An affectionate kitty may tackle these hard-to-reach areas on behalf of her feline best friend. This shared affection can strengthen the bond between two cats from the same household (or colony), so long as both are willing participants.
The purring, head tilts, and sleepy eyes are usually positive indicators that both kitties are enjoying themselves and the bond they share.
Taking On That Motherly Role
Though we liken maternal instincts to adulthood, cats mature far quicker than we like to realize. An unspayed female kitten may have her first heat cycle not long after gaining independence from mom — as early as 4-6 months!
Queens expose their kittens to allogrooming just minutes after giving birth to them to:
- Clear away birthing fluids, feces, and urine
- Hide the distinct smell of after-birth that lures predators close
- Eliminate the birth membrane that “traps” a new kitten in a bubble-like structure
- Transfer her unique scent to her brethren
- Stimulate the bowels and bladder to release their contents (something that happens regularly during the first several weeks)
A mother cat will clean her litter religiously during their first four weeks of life as her kittens become more independent. The “loving touch” of mom’s tongue never escapes a cat’s memory, and many kitties latch onto those maternal instincts themselves as they get older.
Adult cats may clean each other to send a protective and affectionate message, just as their mothers did with them during those crucial first few weeks.
Asserting Dominance (& Submission)
Introducing a cat to your household can be tense and anxiety-inducing for everyone. It could take adopting a new kitten to learn your senior is territorial, angsty, or a self-described loner. That first allogrooming session you accidentally interrupt will make your heart swoon and eyes light up: “I’m so glad they learned to like one another!”
Though many felines prefer aloofness over pack mentality, every multi-cat household has an unspoken pecking order (a dominance ranking). Dominant cats will assert their “alpha” role through subtle — or not so subtle — intimidation tactics like:
- Hogging the food or water bowl
- Marking (or spraying) prized possessions to say, “This is mine, now!”
- Chasing, swatting at, stalking, or pinning the other cat down
- Blocking another cat’s pathway or cornering them
- Staring at one another aggressively
- Grooming the other
All grooming may not fit into the above list cleanly, but it’s certainly a dominant cat behavior that many cat owners coyly overlook. Those sweet feline baths are a secretive way for alpha cats to spread their unique scent into a submissive kitty’s tufts.
Even if the intentions aren’t as noble as they appear, a stable household hierarchy will maintain peace and lend you some peace of mind. Dominant cats soothe their underlying aggression with an impromptu cleaning session. Submissive cats appreciate the relaxation of a seemingly courteous allogrooming session.
Regular feline grooming can be obnoxious and an inescapable misophonia trigger. The 21-minute video below shows that allogrooming between cat siblings is an exception:
Unless your cat’s travels lead to an ankle-deep mud pit, leave that full bathing session (tub, shampoo, and all) off your to-do list. But don’t assume your cat’s hygienic prowess takes all grooming responsibilities off of your shoulders.
Remember that cats have sandpaper-like tongues filled from edge-to-edge with backward-facing bristles. When large clumps of hair (from grooming) become trapped in these bristles, there’s nowhere to go but into the digestive tract.
Leave the sanitizing to your cat and her trusty tongue. And for you: Brush your cat once or twice a week to loosen (and trap) any dead hair follicles.
- SPCA of Texas: Cat Grooming
- Wikipedia: Social Grooming
- PNAS: Cats use hollow papillae to wick saliva into fur
- PetMD: Nail Biting in Cats
- J. Ethol: The Function of Allogrooming in Domestic Cats (Felis silvestris cams)
- Pets WebMD: Cats Arthritis Symptoms, Pain Relief, Treatments, and Types
- VCA Hospitals: Estrous Cycles in Cats
- PetMD: How to Deal with Territorial Behavior in Cats
- PAWS: Aggression Between Family Cats and Feline Social Behavior