Cats can drink salt water

This is true within limits

On average, a 5-kg cat needs around 250 ml of water a day. 250 ml of seawater contains about 8.75 g of salt, and the fatal dose of salt for a 5-kg cat would be 20 g of salt. In other words, this ability works within certain limits, so please don’t go out of your way to give salt water to your cat.

The fact that you need to tell people not to intentionally give their cat salt water is telling of how far we've regressed as a society.
- Humans are naturally curious and lean towards the scientific method, that's why we always need a disclaimer, don't TRY this, they still will.
Still, that's pretty impressive. Cats are absolutely incredible animals. I'm thankful the "worst behaved cats" still love me for whatever reason because I've been able to see some of the crazy shit they do.
My parents have an entirely blind 18 year old cat. She can navigate the entire house eats fine, plays a bit. Hops up and down furniture, finds the sunbathing spots, uses the litter just fine. You do have to keep an eye out for her if your moving around as she can't smell fast enough if you step in front of her path.
- I'm trying to imagine the world from this cat's point of view. Relying on smells, sounds, touch and vibration. I bet she can hear and smell small critters just fine, but would she be able to successfully hunt them?
please don’t go out of your way to give salt water to your cat
Advice to live by.
Don't tell me what to do! /s

Hey, look a feature every mammal may need to evolve in the near future!

Looks like I picked the wrong week to stop fucking cats.
- When was the right week?
- We need you back in the fight soldier, we need to make cat girls (and boys) a reality.
- I've been fucking the dog for decades.

They can drink salt water when times are tough but it still wouldn't be good to drink it for a sustained amount of time.

Especially when kidneys are often the first part that craps out when they get old
I'm sorry, have you looked around recently?
- Last time cats drank this much salt water was the Hoover administration!

Don’t cats often die from kidney disease? :(

yep, usually the first organ to fail in old cats, so the superpower seems to come with a drawback. edit: removed inaccurate statements
- That's why they don't like taking baths
Yes, but often as a result of a long diet with chronic dehydration from a kibble based diet.
The moisture cats consume is from their prey. The blood and juices of rodents and birds hydrate cats.
Canned/wet food cats tend to wind up with thyroid issues instead of kidney. (Well, sorta: there's evidence the BPAs in cans and mercury from fish as a reason for that.)
- Well this is partially true. I'm pretty sure even a cat on a perfect diet will still have very high chances of developing chronic kidney disease in old age because it is just common in cats.
  Could be wrong but my understanding is that It's partially because their kidneys are so efficient that they often get kidney disease in late age. They're always under a super high workload.
Old age, in and of itself, doesn't kill any living thing. There's always a system failure eventually. Seems like in cats that's commonly kidneys or thyroid.

They say the same thing about horses because of their kidney to body size ratio but it's simply not true. It might help them survive on saltwater longer than a human would but it's still a death march.

I could see that since horses require a salt lick anyway.
- I feel like that just because of their body size and the fact that they sweat.

Evolutionary household cats are damn near perfection.

Not a crab
- Part tortoise on account of the tortoiseshell, which is an adjacent water animal
- Not a great white either. Basically unchanged for hundreds of millions of years and absolute apex in every way.
Purrfection

I could say that is an impressive evolutionary feat, but instead I'll say: Evolution, what the hell is wrong with you? You do know we all came from the sea, you should know 70% of the earth is covered in salt water, why did you think it was ok to devolve the ability to drink salt water but retain the requirement to drink water? Are you Ok? Do you need Jesus?

kidney disease is one of the most common ways cats die of old age so super efficient kidneys dont come without a tradeoff. Cats have evolved to live in very arid enviorments where saltwater is all that is availible so the tradeoff might have been worth it. ability to drink saltwater only would work without kidneys being prematurely overstressed would be likely if animals had higher normal salt content but that would mean they would need a lot higher salt intake making living inland harder.
- IDK man, whales can live over 200 years.
Evolution is considered a success if the animal lives long enough to successfully mate and nothing else matters to mindless evolution. At least cats don't have curly tusks that borrow through the skull if they live long enough like that infamous boar species I can't remember the name of.
- Success is being better about producing offspring that can grow old enough to produce offspring better* than everything competing for your niech
  *Better is the more optimal rate. Overpopulation is sub optimal

Penguins too but its in a supraorbital gland in their beak

Gulls too

Sort or related question, is that why their piss reeks like concentrated jenkem?

That’d be ammonia, a metabolic byproduct of their carnivorous diet.
- Not trying to be that guy, but it's urea, which breaks down to ammonia due to microbial action once it's out of the cat. If a cat is pissing ammonia, it has big problems and needs to see a vet.
  Other contributors to awful cat piss smell are mercaptans, the same compounds responsible for the scent of skunk spray, and pheromones and fatty acids released when the cat is spraying versus normal urination. It's all compounded by cats being adapted for arid environments so their urine is much more concentrated than human urine.
  I love cats but they're gross little fuckers sometimes.
Dehydration is a common cause for cats to be 'ill' and brought to the vet,* so it could be that their piss reeks because they are having to concentrate it so much in the first place.
*source: a dimly remembered conversation with a vet friend when I asked her why she was adding water to the already wet food for her cat. She said her cat could never be encouraged to drink enough, so it was her way of staving off the annoyance of giving iv fluids to her own animal someday.
- It's absolutely a thing, I've had several cats in my life look nearly on the brink of death before basically forcing them to drink or eat turned them around completely. They can be very stubborn. Fountains help a lot because in nature moving water is typically cleaner than standing water, so if your cat always refuses to drink, get a $10 cat fountain on Amazon, it works!
- That makes sense, I wonder if it's the case and how common it is. I'll have to ask a vet tech that I know.
Isn't all Jenkem concentrated?
- I'm under the impression that the basic product itself isn't a concentration, but more of a fermented brew.

we're going to need to evolve this superpower if we want to avoid my grandkids and your grandkids killing each other in the global water wars.

we could also just build desalination plants with a field of solar panels next to them, but what do i know

like birds, they will probably eat your eyes first, which is mostly freshwater
- I actually doubt it, they will probably stick to the cat food (not because it loves you or anything they are cold carnivorous predators but it is more familiar)they have left until the body is necessary and the eyes decay first so they would be gross by the time they got to them.
Probably about a week. Cats are desert dwellers, and your meat does contain water, which could buy them a few days.

Can we use it somehow?

Seems oretty obvious. You can let the cat drink the salt water. Then kill the cat and drink the filtered water from it's kidneys.
- Can the kidneys then be used to string tennis rackets?
- Just drink cat piss

More evidence that they are evil creatures

I'm my experience folks who call Cats "evil" usually don't have a very clear understanding of consent or non-verbal communication.
- Cats taught me boundaries and karma as a kid. Lessons all should learn.
- Congrats! You got my biggest eyeroll of the day
- I like cats, but this argument is dumb. The people I know who don't like cats don't like them precisely because cats don't respect boundaries or consent the way dogs do.
You mean superior.
- Found the cat.
Ah yes, because if there's one thing evil creatures are famously resistant to, it's salt.

Airid environment animals that could subsist on metabolic water and blood to an extent. In inland arid environments most standing water never makes it to an ocean, which means it accumulates surface salts and is brackish.

Amazing animal.