The Delightful Mutation Behind Siamese Cats

It's easy to assume a cat's coat pattern is based exclusively on genetics, but that isn't entirely the case for Siamese cats. Their unique coloration comes from a combination of genetics, a fragile enzyme, and losing heat from little noses and toe beans.
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[@theonetribble5867]

So siamese cats look like their own thermal image.

[@duckgoesquack4514]

Now I want to make a heating pad with a picture and stap it to a siamese kitten.

[@hmdshokri]

Big brain...

[@FlurAhFlur]

Duck Goes Quack you mean cooling pad? ~

[@Rebar77_real]

@@FlurAhFlur Why are there cookie cutters in the freezer? lols

[@QuadroMemes]

Predators (the illegal type) also want to know your location

[@l0lLorenzol0l]

You forgot another thing with siamese cats: As they age and naturally get less active they also get darker, to the point you can almost tell their age from how dark they are.

[@Neventual]

Explains why Gamgam always needs a blanket.

[@thechocobotamer6938]

Huh, now that you mention it, we had an older siamese cat at the shelter I used to volunteer at. His name was Bob cause his head would bob due to à neurological disorder. He struggled with the litter box and he wasn't very good at walking, but he was a good cat

[@jessica.a.markert]

I wondered if anyone had beat me to “um, actually” this point... grew up in a house full of Siamese and Colourpoint Shorthairs so I’ve watched them go from baby white to almost solid. Overall a great video - have spent a lot of time studying feline genetics (first place at the science fair!), but never had anyone explain the science of the enzymes at work

[@chasedbyvvolves9256]

@@thechocobotamer6938 it's because the quickest way to get a good siamese is to line breed, but that also causes issues to pop up at a higher than normal rate.

[@ladysilverwynde]

Oh wow. That explains why my Sammy was so dark in the last few years of his life. I lost him at the age of seventeen. I miss him. 😢

[@OMalleyTheMaggot]

I really like referring to a part of a cat as the "central core"

[@SirNeutral]

"Captain Mittens! We're losing too much power in the central core!"

[@deadpanbog70988]

So thats why cats purr....its powering up

[@TheCimbrianBull]

@@deadpanbog70988 ROFL! 🤣 😂 😅

[@resourcedragon]

To be fair, they also talk about human core temperature.

[@gabbonoo]

@@resourcedragon Spoiling it with your logic and reason. Yucky! Ima stick with Battleship Mittens

[@ICEBUNNo]

So basically Siamese cats are furry, walking mood rings.

[@IQzminus2]

Exactly what I thought! I scrolled down to see if anyone had made a comment about it. Siamese cats will forever be known as ‘oh that cat that is a mood ring’ in my mind from this point on

[@DerpDerp3001]

That works very slowly.

[@KohenBlassingame]

So hypothetically if i raised a Siamese kitten in a house with the thermostat low enough it would be brown

[@KororaPenguin]

I haven't read all the Cat Who... books by the late Lilian Jackson Braun, so I don't know if she knew this particular fact.

[@ashleyunderwood4855]

😂😂

[@berryberrykixx]

I watched this boy in my icon from the day he was born to the day he passed. He went from white, to red ears and tail, to a little bit of a mask, then in his later years all of his fur was cream to orange with little individual furs of black here and there on his face (his mask), almost like an old man turning grey. He was the best boy ever. It's been 4 years since we said goodbye and I miss him every day. ❤ my Noah.

[@Fluffynator-hm5hq]

@@athirkell the cat in his pfp

[@marios1861]

awww im sure he had a great time with you

[@brigidtheirish]

Awwww. Sounds like your kitty had the best life.

[@karengerber8390]

♡

[@OMartinez91]

@@athirkell he sounds like a good kitty. I hope he is having a wonderful time in kitty heaven

[@Abcflc]

I had a Siamese cat for 17 years and I just found out about this- mind: blown.

[@somethingwithbungalows]

Old boi

[@GewelReal]

brown*

[@GLITCH_-.-]

Try cooling her down for a few month = New cat!

[@eduardochavacano]

Siamese cats are from Thailand roght? And they may just be ordinary there. but in other countries in Asia this is very expensive cat.

[@DeadInside-ew8qb]

My Siamese lived to 20 😞

[@leelulady2010]

I used to have a Siamese mix. The fur on her sides looked like roasted marshmallows. She still had the blue eyes, dark points and "voice". I rescued her from literal death. Her owner was dragging her by the neck on a rope to dump her somewhere or kill her. I begged to take her from this stranger. She was one of the best cats, so sweet and loving! She had feline leukemia and lived several years with us until she passed away. This was the 80's.

[@srrk3500]

Bless your heart. Thank you for saving the poor animal from the devil.

[@heyimmary1876]

*AWW TY FOR SAVING HERR* siamese cats are so cute man

[@eduardochavacano]

are those cats expensive compared to other cats?

[@erika_7777]

@@eduardochavacano Depends where you get them. All cats are usually the same price at shelters. I got my Siamese tabby from a shelter for the regular price. We picked him because he was the sweetest.

[@marisaramos7421]

How terrible how some humans can be so wicked with cats .god bless your good heart aleays ❤❤❤❤

[@BJ-eh4ol]

Siamese cats are the absolute best cats you could ever have. I'll never have a different breed again! I've had my adorable siamese mix for 13 years and she still acts like a kitten and talks to us all throughout the day

[@picklep9812]

B J my Bengal mix is 20 and still acts like a kitten.. she can’t play as much due to arthritis but people think she is about six and sometimes think I’m pulling their leg.. sorry had to gush 💞

[@RandyContello]

my girl is 16, had her since 6weeks and still acts/plays like a kitten

[@allieconzola]

What about my tortie point Siamese? She’s mostly got the common Siamese coloring but she has one white paw! Also, as I had this video on, I looked at her and whispered “This is about you.”

[@Vocalinds]

Is she purebred? There might be some other genetics in there. Birmans and ragdolls, for example, have color points but also white paws.

[@davidhadley6164]

Cute. My mixed Siamese, Tuna, had a white coat but now it has mixed bloches.

[@JustAnotherBuckyLover]

Generally speaking, calico (or tortie and white in the UK) cats have a white spotting gene, and this white spotting gene will blank out whatever colour should have been there, in the patches in which the white spotting gene is expressed. And it sounds like your gorgeous girl happens to have a patch of white spotting on her paw, hence her missing sock (or as someone else suggested, a birman sock might do it too). She sounds freaking adorable. 😻

[@JustAnotherBuckyLover]

@@davidhadley6164 As far as I understand, that tends to happen because as the cat gets older, their skin temperature tends to drop a little because of age and also change in body volume to the surface area, and that can be enough for the fur to darken overall. If she also has a calico/tortie type of marking as well as the siamese pointing gene, then that might explain why there is patchiness - just enough pigment is able to form in the darker "black" patches, but not enough in the "ginger" or "white" patches. I love coat colour genetics in animals, they're so fascinating!

[@aerynsunx]

As far as cats are concerned, it's always about them.😸

[@kingdmind]

Talking about “tiger” cats, I took care of a mixed, mostly orange cat that had triplets: all completely orange, and 2 of them were female. Pretty rare, NGL. She also once had twins, and the female came almost like an albino; she’s practically pink! Its really cute and I’ve never seen a cat like her. Only in a vid of a kitten that was a little bit darker

[@jelatinosa]

Really not that rare

[@hectare]

i can understand adopting a pregnant cat, but...why did she have another litter?

[@sil_mang]

@@hectare I cant speak to that man's exact situation but I had a similar case with the stray adopt my family. She just would not leave the porch and it became clear she pregnant so we took her in. The vet said to bring her in when the kittens where weaned so she could be spayed. When we took her in around a month after delivering she was already pregnant again. It can happen pretty quickly. We managed to REALLY lock her down after the second litter and got her fixed. But a cat in heat is force to contend with. Especially a stray.

[@carriedulaney2191]

King D - Mind my cat is a female orange tiger but with like a buff wash.

[@kingdmind]

I forgot to add they are strays. They aren’t exactly adopted, but they like staying at home and I take care of them as if they were my own

[@Gaby-wi4bx]

That explains why when I got my siamese cat spayed, the hair on her sides, which were shaved, started to get significantly darker, she was getting cold! 😂

[@katiekane5247]

Likewise the scrotum on my male Siamese, Scamp. We made fun of his southern exposure until it changed back.

[@stygian8049]

@@katiekane5247 that poor schmuck, having people laughing at your balls

[@SadisticSenpai61]

@@stygian8049 Worse. At your lack of balls.

[@NckJonasluver]

Vet here! We try to spay show cats such as siamese underneath their belly instead of on their sides so that the darker fur isn't as obvious when they are shown! :)

[@MotoCat91]

@@NckJonasluver Alternative method: shave a heart shape into the fur so that it grows back as a chocolate heart on their side (obviously not appropriate for show animals, but would be super cute for a family pet)

[@emmettroden5621]

My poor kitty must be cold all the time then, because he’s pretty dark. He’s a Seal Point Siamese. When he was only 1 month old though he looked like a little fluffy storm cloud. It was so cool watching him change colors as he got older. He’s almost 2 years old now. They grow up so fast!

[@prawn_]

That's an adorable MEWtation indeed! Alright, I'll see myself out.

[@Nekomosh004]

OwO

[@phoenixstrills2289]

r/punpatrol

[@SouthernGothicYT]

they're mewtants

[@ThomasNimmesgern]

A CATastrophe of a dad joke. Well done!

[@crystals-r2551]

No. Stay

[@LockedPuppy]

They're wearing their own heatmap! .. that's so cool!

[@inzomniacZz]

Just recently adopted a Siamese kitten! Her name is Mia, she’s not full blood Siamese but still looks like one nonetheless. I’ve always been fascinated by them, so when my uncle’s cat had a litter before he could get her fixed, I had to take one. The momma was a stray tabby he took in, and the father was the neighbors male Siamese. All the Siamese babies were female funnily enough, so we picked our Mia. As she’s grown, she’s developed tabby like markings on her extremities, very reminiscent of her mommas stripes. She’s got a lil M on her forehead too which makes her name perfect👌

[@bast713]

You should look up lynx point siamese, because I'm pretty sure that's how the breed started. They're awesome

[@ColoredMud]

I have a flame point siamese and he's extremely cute. I just thought that was important information.

[@DoctorProph3t]

This is important scientific data, thank you for your contribution to science, your nobel peace prize is in the mail.

[@ColoredMud]

@@DoctorProph3t I'm so honored! I've always wanted to make a difference. This is only the beginning for me as I will continue to push myself to greater heights and who knows, perhaps my contributions will impact the future generations long after I'm gone. But yeah my cat is indeed a cutie pie.

[@helpgirlimhavingalifecrisis]

Omg me too! I found her at a shelter though. We named her Gucci as a joke until we realized well . She actually is!

[@LeatherNeck1833]

"So, what color is your cat?" Infrared

[@littlerougue]

A siamese chose us last year showed up out of the blue and she fit right in with the dogs and even has pretty much ran the mice out.

[@lapillus2344]

That just happened to me! All of a sudden out of nowhere, a beautiful siamese came on our porch. I'm not religious, but I think he's a reincarnation of our old rescue. He was friendly right away and we're trying to introduce him to our dog and cats. What did you do to introduce?

[@SweetStuffOnMonarchLane]

Siamese are the best! =)

[@erika_7777]

@@lapillus2344 Just introduce them slowly and with supervision. There's tons of videos on it. I recommend kitten lady.

[@massimookissed1023]

1:08 had to pause to Google _Siamese Mouse._ Apparently they _are_ a thing. And adorable. Siamouse :)

[@eyywannn8601]

I searched up Siamese human. They did not have super cute boots or a brown mask.

[@carlorielmendez6505]

For guinea pig and rabbits the variation is called himalayan if I recall correctly. Red eyes (signs of albinism, humans and I believe cats rarely show pink eye albinism due to different eye structures), white bodies with black tipped parts like the nose, ears, feet, etc.

[@salsapigeon]

Thank you for convincing me to look that up

[@thunder_2124]

Naji Bro I’m Siamese human cause I’m Thai

[@allanrichardson1468]

Carlo Riel Mendez Humans do show red eye albinism.

[@theCodyReeder]

The dark spot on Buddy’s back is due to excessive grooming removing hair, lowering the temperature. Cool!

[@dw3695]

Hey Cody nice to see you here

[@jogaile705]

Codyy!!!!

[@Razorcarl]

Yeah it is pretty cool

[@flickeringtorch]

Looks like you have a ginger kitty too, too cute!

[@jessicawilson1751]

My siamese cat has a dark belly from where she was shaved for her spay.

[@chepulis]

Charlie Kelly was right, we need kitten mittens. Also, a ski mask and a tail beanie.

[@WSmith1984]

Cats love milk, but would they like Milk Steak?

[@cristianvillanueva8782]

@@WSmith1984 I'm sure they'll eat milk stake with side of jellybeans, raw, ofcourse.

[@cho4d]

came to comment section just for this. was not disapointed.

[@zazuzazz5419]

Stasys Čhepulis Mee ow!!! 🐈

[@abethepunk]

Tail beanie 😂

[@AuntBibby]

there’s something even MORE interesting about the genetics that lead to male calico & tortoiseshell cats, and why they’re so rare! from wikipedia: *Tortoiseshells are also known as calimanco or clouded tiger cats, and by the abbreviation "tortie". Tortoiseshells have patches of orange fur (pheomelanin based) and black or brown (eumelanin based) fur, caused by X-inactivation. Because this requires two X chromosomes, the vast majority of tortoiseshells are female, with approximately 1 in 3,000 being male.[12] Male tortoiseshells can occur as a result of chromosomal abnormalities such as Klinefelter syndrome, by mosaicism, or by a phenomenon known as chimerism, where two early stage embryos are merged into a single kitten.*

[@denniskibrik7310]

well, not fully related to the video but i can say you're smart. now i know why most tortoises are female

[@coconutconure]

Loved this episode, this is so cool! Thanks SciShow! This reminds me of my Siamese cats that recently passed away, R.I.P. Blaze and Blitz.

[@thalionraw9747]

I give you my condolences.

[@denniskibrik7310]

F

[@femmedracula6857]

Something you didn't mention that I've seen in action is that cats with Siamese coloring who live in colder climates will see their fur darken all over their body, although the paws, tail, and nose are still darker. Move them to a more temperate climate and the fur on their body will begin to lighten again as new fur grows in. This is also applicable to different colors, such as flame points. This is distinct from darkening with age, and I've seen it in action in real time.

[@easternlights3155]

"Mittens on your kittens"... I love you, Hank.

[@jerry3790]

I have a Siamese cat, so this is pretty interesting to me.

[@colehalford1893]

Me too Jerry Rupprecht 👍. 👁 ❤️ 🐈

[@locust76]

I have a flame point siamese, this makes total sense

[@thatgirlreacts5465]

Jerry Rupprecht Siamese are the BEST!!!

[@whoever6458]

I think I have a siamese cat but he's all brown except for his belly and paws.

[@xjonnybro]

I have 2 and the definitely get darker with age

[@jonathascordeiro9629]

1:51 I have a male Siamese cat and well..you forgot the balls

[@thatgirlreacts5465]

Jonathas Cordeiro hahaha

[@PrimroseFrost]

Mine no longer has that particular body part, but the bit that's left is just a tiny brown dot when he rolls onto his back. It'd be very tempting to poke, except, well... no.

[@JustAnotherBuckyLover]

Having had male smeeze rats - I totally second this. The balls are one of the darkest (and also, funnily enough, the softest furred) parts of a siamese rat.

[@clamdove3292]

@@JustAnotherBuckyLover how do you know they're soft

[@majaxxi2437]

@@clamdove3292 He merely conducted scientific research

[@crawfishie]

We're learning about this in my biology class and I got to show off my lynx-point siamese cat on the zoom call :D

[@limalicious]

I have an elderly Siamese with allergies...I guess that makes him a sneezer geezer meezer.

[@SirNeutral]

Or a geezer meezer sneezer.

[@patriciaroysdon9540]

Awwww!!!

[@marymaryquitecontrary]

Oooh, meezer insider joke! 🌟🌟👏👏💞

[@erika_7777]

My Siamese gets sneezey too! Usually, once he starts sneezing, he can't stop until he gets to 30. I feel so bad every time, but also can't help but laugh. Thankfully he only does this like once every couple months.

[@Cheeseybacun]

I wish I could isolate and eliminate "yelling at my the top of the lungs 24/7/365" gene from my Siamese cat.

[@armaros820]

but they just want to talk to you :P

[@leaillex]

Himayalan ragdoll- and FUCKIN SAME LITERALLY NEVER GETS A SORE THROAT EITHER??????

[@thatgirlreacts5465]

Cheeseybacun why? It’s adorable!

[@sirBrouwer]

Siamese are just like that. that is part of there breed. the only thing that could help is to get the cat tired by exercise and playing. they have a lot of energy.

[@Cheeseybacun]

@@thatgirlreacts5465 Trust me, it gets rather tiresome after 12 years.

[@ThatOneScienceGuy]

I learned all about this when making a decision last year to get a Siamese cat. Well, technically she is a Balinese, which is closely related to the Siamese and develops the same coloration for the same reasons. They are such great cats.

[@_REVERIE]

Kitties! When my parents adopted my first kitty when I was a baby and they thought he was Siamese but then he grew up alongside me and he turned into a gorgeous brown tabby with a big ol' bullseye on his side! I miss him... He was inseparable from me and would sleep in my crib, he would wake up my parents to take care of me in the middle of the night when I woke up.

[@Marco_Onyxheart]

I'm a simple man. I see kitty, I click.

[@leobottaro]

Look at my cat: - You're a mutant! *Cat is now confused*

[@coolnormalandwelladjusted]

My aunt has a cat who’s dad was a siamese and who’s mom was just a random street cat. Her cat looks just like a Siamese but has faint dark creme stripes on her body. It’s very weird.

[@HughLlewellyn]

My two Ragdoll cats have this same color mutation, and I've even had fancy rats with the siamese type coloration. The coloring doesn't just stop with face mask, paws and tails. Over time the entire body darkens, but is still always lighter colored than the extremities. I've always been fascinated by this color pattern. Thanks for this video explaining the science behind it. :)

[@devinc.r.4903]

My mom and I always keep the house pretty cold (~65F) for medical reasons, so our poor siamese mix has gotten SUPER dark over the years. She still has pure white parts on her feet, chest, and chin that she got from her mama, but the rest of her is either dark tan or almost black now, whereas when she was younger she was much more cream-colored. At least we've invested in heating pads...and she's still a princess of course.

[@waterunderthebridge7950]

...So you’re telling me Siamese cats are basically living, oversized mood rings?

[@aisekrem3216]

*yes*

[@MasterFallenHero]

This is a super useful video. We got one of our cats from a siamese breeder who had another cat get in with mom and they were giving away kittens. Our cat is almost all black except a few white spots and the breeder told us he was white when he was born along with the litter. Our vet told us that was a stress coat.

[@diablominero]

Some other cats have the same tyrosinase mutation. The wikipedia article on "point coloration" has a picture of a ragdoll cat with a tabby pattern on the face, feet, and tail, and white on the torso.

[@rhondahuggins9542]

We have a mutant mutation Siamese mix...longhaired, dark brown to sable with deep deep brown points. Look like a fuzzy piece of a famous chocolatey cereal when we found him.

[@marcuscafaldo8831]

When hank said boots referring to the cats feet I LOST IT! 😂

[@loriw.9166]

I have 2 Siamese cats, and they're brothers. Sparrow is much darker than his brother, Humperdink. I absolutely love them! If you don't own one, I highly recommend them, as they make excellent bonds! They also love to "talk"! Thank you for sharing!😊

[@ratsalad178]

I'm not sure why but hank calling a womb 'toasty' made me smile. wholesome!

[@user-vn7ce5ig1z]

Is the coloration permanent once they've matured or will they turn all -black- white if they stay in a warm environment? 🤔 (I'm reminded of those color-changing Hot Wheels.)

[@Code_Ax0]

All white you mean? I think he said the enzyme that makes them darker doesn't work in warm temperatures.

[@DemonXeron]

They will turn all white if they are in a very warm environment for weeks on end I imagine as the enzyme will denature and lose it's function. Though I am unsure if the melanin is stable without being replenished. If that is the case, no coloration will be lost, but if you find a way to cool your cat, they will turn all black. That's ill advised and not recommended though, as reducing any warm blooded creatures body temperature can lead to damage if it is near their core and is very uncomfortable for the creature.

[@jacquejac1840]

My friend has an indoor/outdoor Siamese cat in FL w/a kitty flap. The fur changes seasonally growing darker or lighter depending on the time of year & how much he comes inside for A/C. Sometimes he looks almost all brown, as he's one of the few cats I've ever seen to prefer shade over a sunny spot.

[@fernfeather7665]

I know this was phrased backwards, but even if the cat was kept in a cold* environment, they'd never be completely black. Siamese have another gene on top of the one that codes for the temperature sensitive enzyme - the Himalayan gene, which they must have two of in order to express the point gene to begin with (afaik). The Himalayan gene is a dilution gene. It means that the cat *cannot* be black - all black is lightened to chocolate. This is why you can sometimes see colorpoint cats with different colors - there are different degrees to which dilution can be inherited. Black becomes brown becomes blue (darker grey) becomes lilac (silver or sometimes even lighter than that!); this depends on "how many," dilution genes are inherited. Some breeders breed "seal," point siamese, which can look black, but are actually a very dark brown. None of that has anything to do with the colorpoint gene, either! It's a completely separate mechanism that goes into making these cuties. I also know that they can have patterns (tabby, calico/tortoiseshell) and that sometimes colorpoint cats can be red based (cream / ginger / orange) but still only present at the points. Kind of sad that this was left out since it's actually what gives lots of breeds that strange variable brown look - ragdolls, himalayans, burmese, toninkese, etc. Just like people, as animals get older their bodies begin to become worse at holding in heat. Siamese cats will never stay the same - not just because of environmental factors, but their bodies become colder as they age, meaning that even if they're kept in the same temperature their entire lives, they will slowly become darker. Some very old Siamese cats may eventually have an almost entirely brown coat!

[@brinx8634]

@@fernfeather7665 Thank you, that's interesting information. I once had a Burmese female who had an almost uniform dark, red-brown colour....no points, no socks, etc. Most that I have seen (not that many) have varying degrees of Siamese-like markings, in that their ears, nose, and feet may be darker, but essentially the same colour.

[@tylerensminger]

Never had a siamese cat but I did have a neighbor who had one and it was cute and friendly. Also, the video itself was very interesting to learn about how siamese develop their signature coloration

[@michaelbradley4541]

This was awesome! I was given a Siamese cat when I was one as a birthday present. I loved her eyes so much. I have had several others join the family over the years.

[@ericthompson3982]

One of the cutest SciShow episodes ever.

[@1234bobfox]

This is a good video. I never knew how much I needed to know about cat mutations until now

[@KAST96]

“Mittens on your kittens” is one of the most adorable phrases Hank has uttered.

[@brookenp1501]

i have a snowshoe siamese meaning he has all the coloration of the normal siamese ,but all his paws are white. his legs still have that fade down to a dark color just like a siamese ,but all four paws are white. his mom was a tuxedo cat ,so i think that’s where he gets his white paws from and we think the dad was a siamese.

[@pudgeboyardee32]

I just started fostering 3 sister cats: one is pure black with green eyes, one is torty with green but the third is long haired siamese. The torty also has dark boots, face, tail and ears. Virtually no brown, tan or orange in those areas. I had heard in a cat genetics video that a number of other patterns are influenced by heat, basically any cat with a white base coat like a tabby with orange over white. My male tabby actually has a pattern on his front toes where the pinky he exposes when he covers his nose is darker than the rest of his paws. He also has a rosette on either flank and sandcat cheek dots. Oh and the siamese has ear tufts like a caracal or serval. Between the 4 of them they have some very interesting markings and combinations thereof.

[@seastarcrunchies]

My cat seems to have this! when we got her from the SPCA when she was about 3 months old (almost 9 years ago now), she was mostly white with a little grey, now she's definitely got darker face, feet and tail, though the rest of her body did darken somewhat and go kind of grey tabby (she's definitely not a true siamese). It's really interesting! especially because I thought I got a mostly white cat, lol. Thanks for the explanation!

[@teto85]

As someone who has been on staff for several Siamese cats over the years I can say that without a doubt they have other mutant powers besides their colourpoints.

[@JessicaMatz]

Toast (pictured, left) is my sweet Siamese boy. Once he got very sick and a patch of his fur went white from where he had a fever. He’s much better now and full of snuggles.

[@DayDreamsofaStranger]

Yep, very true. Both himalyan rabbits and guinea pigs develop their color as they age. And the definition of that color on the extremities only gets better when it's cold, but it can also lead to an ashy appearance elsewhere on the animal called smut, as defined by the ARBA. It's super neat to see someone talk about this topic! Its fascinating to be sure.

[@camojoe83]

Been a while since you guys made me say: "Huh, that's cool." Well done.

[@RustyTube]

*Cats:* We are Siamese if you please. We are Siamese if you don’t please. *Hank:* Oh, how adorable!

[@sussekind9717]

I had a gray tabby that gave birth to several different colored offspring. 3 gray tabbies, like her. One was an orange tabby, another one was a female calico, and one more was a tonkinese. If you have never seen or heard of a tonkinese, look them up. They are an interesting breed of cat. Unfortunately, she only lived to be about 8 years old before succumbing to cancer. But she was a gorgeous cat. We will always love you, Snow Blow!

[@masterful7574]

“Intresting” is not a word.

[@seppemanderick497]

The Delightful Mutation that makes Hank Green grow younger every year.

[@juyama7489]

I only got the the “delightful” mutation thing was probably a pun intended nearer to the end of the video.

[@1swerdna]

I only got it after reading your comment.

[@magdafachada6075]

@@xXGeth270Xx de-light-ful

[@kamilrizvi5361]

Y’all HAVE to do an episode on the crazy genetics behind calico cats

[@Tanjaaraus]

I have "backyard" mix. We just assumed he was a ragdoll mix - but he is coloured like a siamese. The funny part is that when I adopted him he was almost entirely white - but he was already 2 years old. I adopted him and moved way up north, so -4degrees (-20 celcius) winters, and he loves being outside. In less than 6 months he went from almost white to almost black, but he have a lighter cream tone on his chest, in his crotch and around the neck - where the heat is. And he have kept that dark colouration since then. It's a bit sad because his markings where soooo pretty before, but I wouldn't want my troublemaker any other way. (Yes it's him in my icon)

[@3possumsinatrenchcoat]

Question, does this mean siamese raised in colder climates will be generally darker/have more extensive coloration than ones raised in, say, desert or other hotter areas?

[@evariste_galois]

maybe, but i know that in general siamese cats get darker with age. i live in brazil (pretty hot) and my siamese cat of 9 years who was very white as a kitten is now brown

[@Cheeseybacun]

I went away on a 3 week business trip for work in January of 2010. During that time, my penny-pinching cousin, who was looking in periodically on the cat and the house, became bothered by my thermostat being at such a wasteful temp with no one home and dialed the heat waaaaay back. When I arrived home the house was about 49 degrees F inside ...and the cat noticeably much much darker all over than I left her. It wasn't until spring when she started regaining her contrast again, although it never was quite the same again.

[@thatgirlreacts5465]

beatriz b m literally same!!

[@user-kp1bx4zg6z]

Yes, when we had a ~40°C all summer my cat went all white but quickly returned to normal in the autumn.

[@chuckoneill2023]

3 possums - yes, that is exactly what happens. As a child living in Indiana, we owned a pure-bred Siamese. She was a mostly indoor kittie - with quite a few outdoor excursions. Her coat definitely was ver dark towards the end of her life. Later in life, I lived in Tucson, Arizona. In that part of Arizona, it seldom gets below freezing, even in winter. My ex owned a Siamese, which was nearly all pure white, at the age of about 3.

[@spadekersey4102]

Hope you all are staying safe during all of this! Thanks for making this quarantine bearable. ❤️

[@idunnobutyay2520]

I want to adopt a Siamese kitty one of these days. Also, those little meezers are too cute!

[@jacobbaumgardner3406]

Fascinating. We have two half Siamese half tuxedo twins and I’ve noticed they’re fur darkness has changed through the year, and here in the PNW it’s cold and wet for a good chunk of the year.

[@TooLittleInfo]

Let's be honest though, everything about cats is a delightful and adorable mutation.

[@Vivaldimort]

Myth busting time: You may have heard that Siamese cats are "unfriendly" or some other bad thing. That is a MYTH. The opposite is true in many cases: Siamese cats attach deeply and frequently seek attention; since they're diurnal, they actually become quite used to spending a lot of time with you, much like a puppy. Personally I suspect people develop this antagony because Siamese might be perceived as fancy. Fun fact: they may be diurnal because their eyes are barely reflective so they can't see as good as other cats at night.

[@jrt818]

We are Siamese if you please.

[@SoloFaerie]

Aside from lady and the tramp, I didn’t know they had a bad rap. I’ve had numerous Siamese cats in my life, and they are sweet, talkative kitties.

[@sendmorerum8241]

Myth busting time: I don't know where you heard that "barely reflective" thing, but according to breeders (and nighttime photos), the tapetum lucidum in their eyes is totally fine and normal.

[@OcalaBrew]

Fascinating! I have had many Siamese cats, and never knew about this, so I was surprised and delighted to gain the knowledge. Thank you!

[@naughtynarrator5323]

Fascinating, I have a flame point Siamese, so instead of the traditional brown tips, they are red/orange. There are some flame points like him due to cross breeding with orange tabbies, but sometimes it is due to a truly albino mutation. You can tell the difference in the coloration of the eyes, in an albino, the pupils are a pink color.

[@kikicogger2284]

I wonder if that’s also the reason almost all Siamese are blue-eyed, because their irises are at body temperature, causing a lack of melatonin.

[@Camphorous]

It isn't. That's actually a completely different gene that can express in oriental breeds without the colorpoint coat. However, the white masking gene will cause blue when it expresses over the eyes and deafness when expressed over the ears.

[@raerohan4241]

Melanin! Melatonin is something completely different

[@raerohan4241]

@@Camphorous Actually, the blue eyes _are_ caused by that gene. Every single pointed cat, regardless of breed, is _always_ blue-eyed. This is because points are a form of albinism. Mink and Burmese/sepia cats (caused by a mutated point gene, which allows slightly more colour) can have eye colours besides blue, but it's rare to uncommon depending on the breed.

[@themermaidstale5008]

Lack of melatonin is why they don’t sleep.

[@sendmorerum8241]

@@themermaidstale5008 LOL

[@rfldss89]

Inb4: everyone becomes a scishow patreon just so they have access to the floof channel of their discord.

[@AnandAkshar]

Even the science around cats is adorable.

[@savary62]

I had a cat who had a Siamese father, and orange tiger mom. He started all white with the typical blue eyes. But as he grew, rather then the brown feet, face ant tail, he had orange tiger face, feet and tail. Also he had the typical friendly tiger mentality versus the Siamese aloofness.

[@Sam-ux8gh]

@SciShow is this the reason why my arm hairs are blond and my hear on my skull is darkbrown. if it is not, Im interested in how genetics influence differences in fenotypes of different areas of the body. Great vid btw!

[@WolfAdvocated]

Hmm, interesting! I also know several men who have ginger hair, only in their beards. I'd love to know the science of that too.

[@craigcorson3036]

How can you spell "hairs" correctly, but go for a completely different spelling for "HAIR"? Also, *phenotype.

[@Katzztar]

@@craigcorson3036 That misspelling is simple.. typing too fast and not checking for mistakes... excuse I just did that and need to remove the 's' from 'checking'.

[@Primalxbeast]

@@craigcorson3036 You never have any typos, and are puzzled by people who do have them, which is only like 99.99% of the population?

[@svenskayami]

This is how my persian cat is. Found out it was tied to color after he was shaved 😅 good thing it goes back to normal. Just takes a while

[@bek7562]

This is so funny! My Siamese mix was born during the summer and the inside of the house was pretty warm year round due to the Southern temps. He only got a mild roasty toasty color on the most extreme tips of everything.

[@FalbertForester]

Great job on all the COVID-19 videos, folks at SciShow! And thanks for the break, with a SciShow - styled cat video!

[@alisoncircus]

"A few degrees" should be "a few fractions of a degree"; a few degrees would actually be a very large variation, much larger than would be the case.

[@na195097]

alisoncircus There are a few degrees F in 1 degree C. The script was probably in F originally.

[@Notacladist]

Actually, the temp is about that much less in the extremities. That is why you don't take the temp of cats or humans from the extremities. It is that different. And in sled dogs, for example, their legs can be over ten degrees lower in temp than the core temp.

[@rsrt6910]

I just used my thermal imager on both of my Maine Coons. Core body temperature (externally) was ~75F and the paws and tail were ~68F. 7F temperature spread.

[@janetross1900]

That little decoration on the rear end of that male cat must get cold, too

[@raneemacintosh6842]

I had a cat with the Siamese coloring, a sweet, scared little stray who visited my house when I was seventeen, and he's the one who made me love cats. Interestingly, since he lived outside, he was nearly white during the summer but got to a darker, slightly brownish beige in the winter. At the time I thought it was just the contrast with the snow making him look less pristine. Also, we weren't sure if he was a boy or a girl cause he was too skittish to be touched....until we saw his little dark-coloured nutsac LOL

[@frattman]

Thanks for the "Always Sunny" quip Hank!

[@emmaabigail4196]

*Me, looking at David Blaine, my siamese cat*: "David Blaine, look! That's your family!" David Blaine: mother, the very center of my bowl lacks sustenance. Why do you starve me? Me: But... what about the ring of food all around the sides? David Blaine: That is for the common cat, filthy human. I am a king. Do not incur my wrath.

[@HughLlewellyn]

hehe

[@LePezzy66]

The distraction I need from studying genetics haha

[@nariu7times328]

I love that they show images of the protein structures...

[@angelfood8419]

Super cool! Thanks for the info!

[@nunya321]

"jag-wire" 🤣🤣🤣

[@somethingwithbungalows]

Random Dude how are ya supposed to say it? Lol

[@nunya321]

@@somethingwithbungalows well he's pronouncing it w a common accent so it's fine... but generally the word should be pronounced jag-wohr

[@denniskibrik7310]

@@nunya321 it's jag-w(aa)r, i'm not sure if it's a accent but i pronounce it that way

[@Strawberrypaws]

What about Birmans and Ragdolls, whom has white toes (and sometimes white on the face, ragdolls), is this the same gene or something different?

[@HughLlewellyn]

It's the same. But they can have a broken color pattern caused by varying amounts of melanin in the skin on their feet that gives them the white mitts. I have two Ragdolls. One has dark feet, mask & tail with the traditional sable coloring, the other has white mitts and her color is called blue lynx point mitted. Her extremities are a blue-grey with faint darker stripes. Her body is a lighter, softer grey than her extremities and you can't really see the stripes, except on her legs, face and tail. They're both 11 now, so their bodies have darkened, but they never get as dark as their color points.

[@teddydoll10]

Yes, I assume it’s just like how a tuxedo cat (black and white), for example, has areas of white throughout the coat. Ragdolls has Birmans with mittens etc just have those areas of white fur that would occur with or without the tyrosinase mutation.

[@sendmorerum8241]

No, they have the "white spotting" gene which produces white patches no matter the temperature of the body part - just like it does with simple bicolour cats, but Birmans and Ragdolls also have the Siamese gene added on top.

[@veryberry39]

This may be my favorite SciShow video.

[@fridakahlo4225]

I guess this mutation also helps to balance their body temperature. As it's said that nose, ear, tail and paw areas are likely to loose heat more than torso. And we also know that light colours reflect the heat and dark colours emitt sunlight. So those cats fur help lower the torso temperature and increase the extremes temperature.

[@ikeekieeki]

i had no idea! what a "cool" fact

[@jacobandrews2663]

So what would happen if say, a siamese cat grew up somewhere along the Ecuador? 😮

[@sam-un1px]

Jake Andersen Well siamese cat originated from Thailand. So I don’t think there will be much differences in term of coloration.

[@hclnet]

The temperature of their environment can have some impact on their color, If they spend a lot of time outdoors they will darken slightly in the winter and lighten in the summer. They also will darken over time as they grow and the average temperature at the surface of their skin is slightly less than their core.

[@camojoe83]

The what?

[@ratsalad178]

@@hclnet wow, have you seen this happen in these cats?

[@hclnet]

@@ratsalad178 Yes I've had several and they all darkened as they aged. I adopted a red/flame-point (the color points are orange) who was an outdoor cat, but became an indoor cat and he became much more orange in the months after living inside.

[@cathipalmer8217]

We had a beautiful cat with a siamese meow and color pattern, but with a white undercoat and black topcoat. Until he got old and went white with black sprinkles here and there. Rest well, Simon Kitty! I hope someone is playing mouseball with you in kitty heaven!

[@esaedromicroflora1247]

that's the quality content I expect from this channel

[@BooBaddyBig]

Imagine if a human had the same mutation! So weird!

[@sirBrouwer]

well a shirt tan is more or less that. (only the lower arms and face is tanned)

[@onetallpheeesh]

Some do!

[@artoruvidal2793]

They do have it

[@ReineDeLaSeine14]

This type of albinism is possible in humans too!

[@Furby-luv3r]

Any pictures of them??

[@agnosisparadigm4212]

Half my brain when I see tigers, lions, jaguars or other big cats: Awh, look at the kitty I want to pet it! Other half of my brain: Dude, that thing can literally eat you.

[@IQzminus2]

Yeah lucky for us all the big and small cats are all very cat like. They sure have plenty differences. But the things that make us humans go “aw look at that cutie!” they all pretty much share. And I’ll take normal house cat that can’t accidentally bite a big part of my leg of when it gets too excited when it wants to play with me over a Jaguar anytime. And house cats are at least a little domesticated

[@YouTuberOnlineNow]

I own a siamese cat and it's fun seeing is coat change over the seasons.

[@HM-rw5dz]

My sweetest siamese died in February. She my heart and soul..sweetest kitty ever!

[@werelemur1138]

I'm so sorry. It's never easy to lose part of your family.

[@pawzforthought]

*hug* It's so hard, they aren't just a pet, they are a part of you forever. I hope that some day you will be able to look back on her memories and smile instead of cry.

[@HM-rw5dz]

Thank you both for your kind words..she died in my arms laying in bed, 2 hours before the vet appointment to have her put to sleep..stupid cancer but Im glad I got to love her for 14 years! Very blessed