Last time, we explained how cats are physically "liquid" (→Why Are Cats Called a Liquid?).
But hold on a second. Cats aren't the only animals that take the shape of their container.
Hamsters, ferrets, seals, and — surprisingly — lions. The animal kingdom is absolutely packed with a colorful cast of "liquids."
This time, using cats as the baseline score of "100," we went ahead and ranked the liquidity of animals across the animal kingdom entirely on our own authority.
Animal Kingdom Liquidity Rankings (Cat = 100)
| Animal | Liquidity | Liquid Type | Properties |
|---|---|---|---|
| Ferret | 120 | Low-viscosity fluid (flow type) | Moves by "flowing" through narrow pipes. Instantaneous fluidity exceeds that of a cat |
| Cat | 100 | High-viscosity fluid (fill type) | The baseline. An active liquid that willingly seeks out containers to conform to |
| Hamster | 85 | Melting solid (phase-transition type) | Loses to gravity and "spreads flat." Expert at merging with the floor |
| Seal | 60 | Gel / viscoelastic body (elastic type) | Strong skin tension makes it less a liquid and more a "jiggly gel" |
Let's take a closer look at each animal's "liquid credentials."
Mammal "Liquid" Candidates
Hamster | State: Melted (mochi softened by heat)
When relaxed, hamsters go so flat it's as if their skeleton has simply vanished. Spread out on the floor, they look exactly like mochi or daifuku (soft Japanese rice-cake sweets). Having evolved to live in narrow burrows to hide from predators, their ribs flex freely, letting them flatten their bodies and squeeze into tight gaps.
Ferret | State: Flowing (water through a hose)
Ferrets, members of the weasel family, are called "elongated liquids" thanks to their long, slender bodies. They slip through unbelievably narrow tunnels — like pipes or toilet-paper tubes — as smoothly as water. Their flexible spines even allow them to make a U-turn inside a tunnel.
Seal | State: Formless (slime drooping on the floor)
When a seal hauls itself onto land and lies down, its neck disappears into its body and its limbs vanish, leaving behind one giant "water manju" (a soft, jelly-filled Japanese sweet). Their thick layer of subcutaneous fat conforms to the ground under gravity, which is why they frequently go viral for "turning into liquid."
Mouse | State: Leaking (ignoring the laws of physics)
The mouse version of "if the head fits, the body fits." Watching a body far larger than the opening seem to ooze out of a hole just a few centimeters wide is pure liquid behavior. The reason: their collarbones deform easily, letting them compress their ribcage to an extreme degree.
Big Cats Are Perfectly Respectable "Liquids" Too
Lions, tigers, leopards — these massive creatures are undeniably liquid as well. If the domestic cat is "water," then they are ultra-high-viscosity liquids like "honey" or "lava."
The reason is simple: they share the same "floating collarbone" as the domestic cat. Experiments at American sanctuaries have confirmed that when lions and tigers are given cardboard boxes, they react in a way indistinguishable from a house cat — attempting to cram themselves into a box that is clearly too small, overflowing yet stubbornly determined to fit.
The difference is their enormous mass. Because gravity acts on them so much more strongly, they can't go flat the way a house cat does; instead, their style is more of a "slow, heavy droop."
| Animal | Liquid Style | Description |
|---|---|---|
| Snow Leopard | Melting | When lying on rocky terrain, its fur conforms to every bump and hollow. "Cream draped over a rock" |
| Leopard | Draping | Dangling all four limbs from a tree branch — "laundry hung out to dry" |
| Tiger | Filling | Loves water and packs itself tightly into a narrow tub — a high-viscosity liquid at capacity |
Next time you spot a leopard draped limply over a rock or branch at the zoo, try thinking of it as "a liquid so viscous it's still slowly flowing" — it makes for a much more enlightening observation.
Even More Fluid Than a Cat? The "Low-Viscosity" Wild Cats
The domestic cat's liquid abilities are specialized for conforming to containers, but there are wild cats that actually surpass it when it comes to flowing through complex routes.
Margay | State: Superfluid
A small wild cat from Central and South America. It can rotate its hind ankles 180 degrees and run headfirst straight down a tree trunk. While a house cat brakes with its claws on the way down, the margay simply "flows downward" without fighting gravity — a true zero-friction superfluid.
Jaguarundi | State: Laminar flow
Also known as the "weasel cat" or "otter cat," this wild cat has an extremely long body on absurdly short legs. Its appearance is basically "a furry eel." With minimal body contours, it slips through narrow tubes with almost no resistance — better tunnel clearance than a house cat.
Clouded Leopard | State: High-capacity liquid
About the size of a medium dog, yet capable of opening its mouth nearly 100 degrees and rotating its ankles too — a highly mobile creature. It can hang from a tree branch by its tail alone, and its movements are so light for its mass that it creates the illusion of "abnormally low viscosity."
Bonus: Can Humans Become Liquid?
Sadly, the answer is no.
The decisive reason: the human collarbone is firmly locked to the breastbone, functioning as a rigid strut. It gives us stable arm movement, but it also means "the head fits but the shoulders get stuck." Our spines, which evolved to be robust for bipedal walking, have also sacrificed fluidity.
That said, there are moments when humans approach liquid-like states.
- Infants: Much of the skeleton is still cartilage, and babies have around 300 bones (adults have 206). Closer to liquid than adults
- Crowds: In physics, a "high-density crowd" is treated as a fluid. A packed rush-hour train is the human version of a flow phenomenon
- Kotatsu / bean-bag sofas: Both physically and mentally, a state approaching pure liquid is reliably observed (a kotatsu is a low Japanese table with a built-in heater and a blanket — a notorious trap for productivity)
If humans were serious about achieving liquidity, we'd apparently need to restart our evolution from scratch — beginning with "abandoning bipedal walking and degenerating our collarbones."
Bonus: The Love of Cardboard Boxes Transcends All Species
One more thing on the "liquid" theme. Love of tight spaces = love of cardboard boxes is an instinct that crosses species lines.
- Lions & Tigers: Identical reaction to a house cat. They just crush the box instantly
- Rabbits: Don't just get in — they chew it to pieces, the "home renovation" faction
- Ferrets: Less interested in boxes; obsessively attached to tubes connected into a "maze"
- Hamsters & Mice: Shred it and carry the pieces home as nesting material
No matter how unusually "low-viscosity" a cat may be, put a reasonably sized box in front of it and it will attempt to liquefy and fit inside at least once. This is the absolute law written into every feline's DNA: "If it fits, I sits."
Conclusion
There are moments when certain animals outrank cats on the liquidity scale, but "conforming to any shape of container, of its own free will, and holding that shape" — the animal that most perfectly embodies the definition of a liquid is, without question, the cat.
In terms of overall dignity as a liquid, the cat is undeniably the reigning champion.