Why Don’t Fish Freeze in Antarctica? I Antarctic Extremes

Under the ice in Antarctica is a world few people ever get to see.
Subscribe! kzbin.info?su…
Bizarre creatures-ancient sponges, gigantic jellyfish, sea spiders, ribbon worms, and notothenioid fishes that manage not to freeze-make their home here. “Every time I come down here, every year, I always find something I haven’t seen before,” diver Steve Rupp says.
To discover Antarctica’s dazzling hidden underbelly, host Arlo Pérez meets with Steve and his fellow Antarctic diver Rob Robbins, while host Caitlin Saks explores the McMurdo Aquarium with evolutionary physiologist Chi-Hing Christina Cheng. Arlo and Caitlin learn that the Antarctic marine realm is not only spectacular to see, but fascinating for scientists to study. The water is so cold that fish inhabiting it should freeze like an icicle, a phenomenon that evolutionary biologist Paul Cziko uses supercooled water, snow, and fish guts to demonstrate.
So how do Antarctica’s fish, which penguins and seals rely on for food, survive in waters below their freezing point? To find out, Caitlin and Arlo go ice fishing with a local legend, biologist Art DeVries, who has been studying fish physiology in Antarctica since 1961. The secret is an evolutionary marvel that has major implications...for ICE CREAM.
For more cool underwater footage, check out the channel for the McMurdo Oceanographic Observatory (MOO): / @mooantarctica
Or, visit the MOO's website for LIVE (seasonal) underwater footage: moo-antarctica.net/live
--
*****
PBS Member Stations rely on viewers like you. To support your local station, go to: to.pbs.org/DonateTerra
*****
Hosted by Caitlin Saks and Arlo Pérez
Editor/Digital Associate Producer: Arlo Pérez
Producer: Caitlin Saks
Field Director/Cinematographer: Zachary Fink
Executive Producer: Julia Cort
Coordinating Producer: Elizabeth Benjes
Project Director: Pamela Rosenstein
Production Assistance: Matthew Buckley, Emily Pattison, Sean Cuddihy
Audio Mix: Heart Punch Studio
Director of Audience Development: Dante Graves
Senior Digital Producer: Ari Daniel
Audience Engagement Editor: Sukee Bennett
Outreach Manager: Gina Varamo
Special thanks to the United States Antarctic Program
Archival:
Emily Stone, Getty Images, McMurdo Oceanographic Observatory, Paul Czkio, Paul Dayton / NSF, PH1 R.W. Milton / NSF, Rob Robbins, Shutterstock, Steven Rupp, Storyblocks
Music: APM
National corporate funding for NOVA is provided by Draper. Major funding for NOVA is provided by the David H. Koch Fund for Science, the Corporation for Public Broadcasting, and PBS viewers. Additional funding is provided by the NOVA Science Trust.
Major funding for this project is provided by the National Science Foundation. Additional funding is provided by the Heising-Simons Foundation, The Kendeda Fund, the George D. Smith Fund, and the Richard Saltonstall Charitable Foundation.
This material is based upon work supported by the National Science Foundation under Grant No. 1713552. Any opinions, findings, and conclusions or recommendations expressed are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.
© WGBH Educational Foundation 2020

[@FluffyFluffles]

"Likes to touch things" is about the most perfect and totally relatable description I've ever seen of a person.

[@jussayinmipeece1069]

that describes Stumpy my second cousin.

[@axpRandom]

covid: nice

[@unethicallyvoid2888]

That's pretty bland

[@andrewrobinson4019]

I love these two as presenters-mostly because they’re doing everything I would do (touch everything, try to eat everything, etc.)-but also because their curiosity and passion is so clear. I can’t wait for more!

[@lurking_silhouette5802]

Agreed. Also, Arlo is kinda hot too.

[@ejssol53]

Ii8

[@AreHan1991]

Yes. But it's frightening how alienated they are from natural processes. They didn't know that microbes eat the shit, and that's how it's broken down to soil?!?

[@knucklesskinner253]

@@AreHan1991 wait what lmao?

[@dauwg99]

Caitlin is a cool girl!

[@svahn1]

I love this show. It feels like a high quality documentary that you'd find on the BBC or something, but somehow much more personal. And it's being put out by a (relatively) tiny channel with less than 20k subscribers. It's great.

[@zapfanzapfan]

PBS is sort of the American BBC.

[@unepommeverte17]

I've always heard that supercooled water just needs *any* nucleation site to freeze, which is why the bottle trick only works with relatively pure water, and why you can freeze it just by hitting it. Based on my understanding, that test tube of supercooled water would have frozen instantly regardless of whether the fish tissue had ice in it, because the tissue itself would have disturbed the water and provided that nucleation site. Is there something more complicated going on that I'm missing or was this somewhat oversimplified?

[@MOOAntarctica]

Good question. The colder the temperature, the more likely some random particle will cause ice nucleation. Absolutely pure water can stay liquid down to at least -40°C=-40°F. At the relatively low supercooling used in the test-tube experiment, there are very few materials that cause ice nucleation. Ice-free seawater (with all its critters and bacteria) doesn't nucleate the tube, nor does the local sand/sediment etc. And, if we first warm the fish tissue slightly (or even a whole fish!), thereby melting the internal ice - it *will not* nucleate ice in the tube, even over many days---It's a definitive assay for internal ice in the fishes. The whole idea of supercooling is so contrary to our everyday experience, but plays a big part in the world (see for example how rain often forms from supercooled water droplets in clouds). (Finally, hitting the bottle works b/c the pressure wave likely causes local cavitation - a momentary bit of vacuum/air - the edges of which must pattern the initial ice formation). Caitlin and Arlo did a very nice job of presenting this! The one thing that was glossed over is that the fishes risk freezing in the first place because their blood is only 1/2 as salty as seawater - so their normal freezing point should be -1.0°C (30°F), whereas the more salty seawater can get down to its freezing point of about -1.9°C (28.5°F; just because it has more dissolved salt in it). Hence the fishes' need for antifreeze proteins to extend their protection (by stopping their internal ice from getting any larger) to just slightly below the freezing point of seawater.

[@unepommeverte17]

@@MOOAntarctica that's so cool! (no pun intended lol) thanks for the explanation!! :D

[@tomaz720]

I found my question and answer :)

[@PhysicsPolice]

McMurdo Oceanographic Observatory hope you understand I’m not just going to take your word for it. Where is this published? The bit about warmed fish doesn’t nucleate ice crystals, even after a few days.

[@pepeelpollo3647]

yesssssss, i was gonna writte about this, thw fact that he is dropping it about a height H=(y) it has potencial energy equal to pE= m•g•H, that the is transferred to cinematic energy in the lowest point, in the limits:H-->0 and its described by cE={ m[V(H)]^2 }/2 so the freezing energy it maybe because of that and not the explanation he gave about the fish tissue, what do you think?

[@nickryckx7817]

8:24 The guy’s name in Dutch literally means “the frozen one”.

[@dean6047]

Wilde ik net zeggen

[@that_morrigan6184]

That old man looks adorable. He'd be a fun dad. *flashback to 1961* Did I say dad? I meant Daddy.

[@miaphasay5161]

For real, like okay ART 😍

[@xxathenacraftsxx]

Man lowkey looked like Chris Hemsworth fr

[@AntheaPeter]

🤣🤣🤣🤣

[@1jazzyphae]

😂😂😂😍💀

[@panjimartiandaru3081]

That 1961 version is yum 👌🏼

[@revinaque1342]

I find it fascinating that the shed on top of the ice is warm enough to just be wearing a flannel shirt, while the floor opens up to the freezing ocean

[@expiredlamb2000]

Hot air rises and cold air sinks, so the hot air gets trapped in the shed

[@webgoalie]

It's sometimes too warm in the huts at times if the hut has a deisel heater. we often use a small 12v fan connected to a plastic tube to blow the hot air at the ceiling down into the hole to keep the ice from forming on it.

[@Sherwoody]

Reminds me of ice fishing in Northern Ontario. The only major difference from the video was that we had a few alcoholic beverages.

[@Alexander-is9jo]

This episode was amazing. I didn't know that about Antarctic fish. Caitlin -> Likes to touch things 🤣🤣 you should totally put that in your CV. Also, Art looks really attractive in the first picture. I mean I'm straight, but damn. Keep at it guys! We love you.

[@caitlinsaks4910]

"likes touching things" has been a major liability these days.... it's been tough going.

[@GPrinceps]

Yeah, it was a great episode. Gotta love Caitlin and Arlo. Ditto @ Art, he was (is) really handsome! Can't believe he's been working there for decades, that's amazing. :D

[@dogedog2798]

the fishes aren't freezing because they're just built different

[@leafsubsides]

🥶🥶🥶

[@possummagic3571]

MIND BLOWN 😱😱😱

[@vivabratislava]

Fascinating

[@PoundTheAlrm]

RIP other fishes

[@3farrelkeane805]

pog

[@lurking_silhouette5802]

Such a superb quality content. Thanks PBS Terra!

[@revinaque1342]

I've been loving PBS Terra! Absolutely exceptional content and camerawork, and it seems like everyone in Antarctica is passionate about their jobs and so happy to be there

[@daniellongcop1899]

I love that duo, they're so relatable,

[@shubhamsendre2121]

Question : Why don't fish freeze in Antartica? Answer : Antifreeze Protein.

[@miteonmybed]

thank youu

[@jasonlee7928]

Thank you all these click bait videos cause they're so desperate for money lmao Question why does meat give you muscle. KZbin videos: YOOO WHATS UPEVERYBODY BACKHEREAGAINWITHANOTHERVIDEO BUT TODAY THE QUESTION IS WHY DODS MEAT GIVE YOU PROTIENT SHABALABADINGDONG PING PONG ANYWAY HERES OUR SPONSOR AUDIBLE BE SURE TO USE CODE GORILLA TO GET 30% OFF AND PEOPLE HAVE BEEN ASKING FOR MY PLAYLIST SO HERE IT IS...... *1 hour later* ok guys this video is gonna be kinda long because the answer is so complicated so I'll split this video into two parts THANKS FOR WATCHING FOLLOW ME ON INSTAGEAMSNAPCHATTWITCHKZbinCHANNEL#2#3#4TWITTERONLYFANSMYSPACEFACEBOOKROBLOX

[@miteonmybed]

@@jasonlee7928 just think about it, it all begin with simple question, intriguing one, yet simple answer. But they manage to stretch it to a long video. Geez, no wonder so many clickbait video.

[@jasonlee7928]

@@miteonmybed wait YOU THINK THATS HARD? Anyone can stretch an obvious answer into a paragraph long essay. That's what idiots do everyday when they cant give a simple concise answer. What takes skill is continously giving straight to the point answers without all the bullshit and changing topics

[@miteonmybed]

@@jasonlee7928 i didnt say its hard. They just clever i think.

[@benmcreynolds8581]

It's so biodiverse, the animals are so massive, the increased oxygen content really fuels large versions of the critters. It also makes them more thermodynamic I heard. It's amazing they evolved to survive in this freezing temperatures.

[@TheOMT]

I'd expect that the "Ice fished the Antarctic shelf" is not only one of the most exclusive clubs you'll ever belong to but it's likely to stay one of the most exclusive clubs ever.

[@RoseisoutofherTOGA]

“I started in 1961” *cuts to photo* Me: “...Thor?”

[@jauipop]

Wow... Young Art in the 60s omg.

[@MichaelDFPV]

This was fun to watch. Interesting how the fish evolved to live in the freezing water. Space Time sent me 😉

[@sebastiansandhu4695]

I have traveled thru space and time and have arrived ready to learn

[@GoodGolly.MissLolly]

Young Art was a bit of a babe, hey?

[@protercool8474]

Almost as much as old Art

[@martinbondesson]

I don't think I've found a channel where the phrase "I can't believe this channel doesn't have more subscribers" apply more! Best thing I've seen since Blue Planet 2 =) And I think I have a mild crush on Caitlin.. Arlo is cool, too! Love to you all

[@silascochran9705]

I'm glad he mentioned astronauts when I was a child I was fascinated by the space program but now I think man should get his head out of the clouds everything we are looking for is here there will not be life without being in the Here and Now Space Program resources should be used here now

[@expiredlamb2000]

Caitlin and Arlo are just having fun with this. I would like a job like that please

[@0HARE]

Well, this was truly fascinating. Thanks for taking us along.

[@Sparticus142]

This series is absolutely fascinating. I'm so intrigued.

[@awong160]

I'm so happy I found this series!

[@loungelizard836]

Wonderful stuff! Thanks for making these videos!

[@steverundle8635]

Love this NEW site! Thanks so much for showing us all what goes on! All the time!

[@Del-Canada]

I used to love diving below ice and in cold water. Visibility is amazing and so is the variety of life forms.

[@13catfishswim]

Thanks Deep Look for suggesting this video!! It’s awesome

[@unknownscp169]

This was so cool to watch. I love I can see educational videos in 4k!

[@eduardoalvarez9485]

Just came from two cents, cool video didn’t know that much from Antartica.

[@celiaannetta]

“Just wants to hang” 😭😂 most fitted description for me

[@andreykrylov7155]

10:30 Someome is having a crush... And it's me.

[@chuckphilpot7756]

Andy Krylov She has a lovely smile doesn't she.

[@LimeyLassen]

That guy is smooth hahaha

[@morenabuddies6479]

This channel deserves more subscribers! ❤

[@lukkyluciano]

"why are they so easy to catch?" -every fisherman watching this video

[@SmallSonEZ]

pretty sure fishermen wouldnt be the ones asking that.

[@SpaceNStuff]

Give this editor a raise.

[@turgsh01]

Omg, Caitlin is sooo cute! Love the documentary too, I didn't know any of this at all and have always wondered how creatures could live in such harsh conditions but was never able to find videos explaining it properly. So thank you. Also, Physics Girl sent me. :p EDIT: Well, I've watched all the videos uploaded so far... can't wait to see more. :)

[@benlaw7843]

Superb documentary and learning experience. Very interesting 👍😊 Thanks to PhysicsGirl for sharing this 💐💐💐

[@ricardosiervi1367]

Nice to see such small, but very interesting portion of spacetime.

[@belleann]

this honestly deserves more views and this chanel deserves a loooot more subscribers. Millions of ppl should be seeing this 🤯

[@astroloudboy]

9:50 We all know what song start playing in our head when she said "stay alive" 😀

[@vishank7]

This is sooo beautiful! Love it!💎💎💎

[@romanchukanov4454]

Great video. Really would like to know about those parasites, though.

[@0nceinalifetim3]

Yes! Me too. Why are the fish full of parasites?

[@romanchukanov4454]

@@0nceinalifetim3 and since those fish have antifreeze in their blood, is it fair to assume that the parasites have developed the same feature?

[@ReflectedMiles]

Totally agree. In the Northwest US, it is common to try to source fish like salmon from clean, very cold waters for exactly this reason--they tend to be cleaner than fish hanging out in warm water with city runoff. What could cause fish so cold and so remote in the ocean to be heavily infested with parasites? Very strange compared to what I am used to.

[@imadudin2489]

very love this channel...

[@latreclays4246]

2:18 those squid/jellyfish little things are sooooo cute

[@naveenraj2008eee]

Absolutely mindblowing video..👍

[@RiggingDoctor]

This was amazing!

[@avariceseven9443]

Am I the only one interested in those fish parasites mentioned? I thought they'd have none cause the place is so cold and that they just look unappetizing but now I want a follow up to this.

[@PiNKUZi]

At first I was thinking they might be delicious since the water contains a high salt content, but then he mentioned the parasites lol NOOOOPE

[@kaytlinjustis5643]

Considering the fact that Antarctica USED to be full of greenery and life before the ice caps, I'd imagine that there'd still be some ancient parasites and viruses still within the ice and water itself, so it'd make sense that these fish would have parasites in them as well. I've also heard about a 300+ year-old shark being blind through a worm parasite deep in the Antarctic Ocean, from a previous NOVA documentary!

[@r7diego]

Suscribing !!, thanks Matt for the recomendation

[@tempodopop5571]

It's Okay to Be Smart is the reason I'm here. Was never curious why fish don't freeze until now.

[@victoriaeads6126]

These fish remind me of Darters, a small member of the perch family found in North American freshwater, commonly fast running water. Darters are really neat, too! They aren't Anti Freeze fish, but they're benthic, lack a swim bladder, and have fascinating behaviors. I've caught several common species of Darters in streams local to me in Northern Virginia to keep in my aquaria. They are wonderful aquarium fish, especially for a tank of native flora and fauna.

[@lobotzindiegoantesnesslope6004]

Omg Art was hot! Like hot hot, anyways an application could be use for cryogenesis freezing people without damaging the cells

[@peterlustig8021]

This was awesome!

[@av1479]

This is a great video. I 1st in my life come to know that fish can stop freezing. And *space time* has send me here.

[@ankh428]

Joe from It's ok to be smart sent me. Did not disappoint.

[@loumauve]

thank you, Physics Girl! this was hella dope.

[@lithostheory]

10:24 cuteness overload :^)

[@muhmalikali]

The best and the most extraordinary fishing spot

[@stevepinnell453]

Fascinating! Would love to dive here.... :) Thanks to PhysicsGirl for the link!

[@seattleitefpv]

Fascinating!

[@bertoray5497]

I came here through SpaceTime. I will stay and study you earthlings.

[@HarveyMeadowlark]

Steve and Rob are the real MVPs

[@SaphreCoalwolf]

2:38 sure talk about how beautiful it is while conveniently ignoring one of the most terrifying ocean spiders I've ever seen

[@urbanwarchief]

You guys are amazing

[@MiaLens]

Great video, fantastic insight. It saddens me however that the price for knowledge is trapping the fish in pools and cutting them

[@twstf8905]

Paul looks like Michael Fassbender, or a distant long-lost Norwegian albino twin lol the resemblance is striking.

[@rajat0610]

Physics Girl sent me here And I'm glad and thankful!!

[@eyezak_m]

Joe sent me (It's Okay To Be Smart), and I am glad he did! This is such a great video!

[@wesleywmassey7134]

Amazing! 😮

[@digvijaygadhavi7418]

I would have never discovered this Great Unique PBS channel and this Wonderful beautiful life under ice if Physics Girl didn't Told me.

[@fxlxp]

Wow, fascinating!

[@akiragreenful]

Deep look linked me to this vid. Very cool vid, btw

[@nata3467]

This is AMAZING

[@TheDarkPacific]

It's ok to be smart led me down this particular ice hole.. Very cool stuff lol

[@imievelectricvehicleadvent6225]

Physics Girl sent me here and this is cool!

[@EricMcNugget]

Agreed!

[@oqsy]

What’s up chumps. SpaceTime told me to come wreck this joint!

[@depausvandelilithkerk5785]

I am with the Allmighty Lesbian Family street gang so you don't scare me. All for one & one for all! Lesbian Family for ever!

[@ambergris5705]

Gosh, this is one of the best documentaries I have seen in a long time! Everybody is so endearing, the presenters are so nice, the fact that they're two makes it that much more human, and the scientists are given the spotlight, actually instructing us. Usually they are only given one generic sentence on camera before it cuts back to a presenter that doesn't know a thing about the subject. Well done!

[@francessev2210]

Deep look sent me here. Great another PBS channel to subscribe too 🙏

[@mugumyapaultheafricannomad9488]

Just like how there's few divers who've dived in Antarctica, there's fewer people who have visited every single country on Earth than we have astronouts. I like such extreme stuff

[@farhanasharmin8997]

I think there are more astronauts in history then those who visited every country

[@lowwastehighmelanin]

Joe sent me and boy am I glad he did this is awesome content! 👏🏾

[@frozenpine1781]

I also see all these people saying other KZbinrs sent them, but I got here because I was curious what people did with their poop in Antarctica

[@HappiEp]

PBS space time brought me here, and I m thankful for it

[@LaDyFlabiA]

Very interesting

[@cooleyeking7779]

Thanks to Space Time for recommending this video it was great.

[@Padyatra]

Fascinating!!! BTW: Physics Girl says hello :)

[@louchutew1454]

This kinda content is the only reason o still wake up during quarantine

[@charlesthepaperman]

3:12 "... and then we eat 'em"

[@aditya_saha]

i am so fascinated by Antarctica

[@Swnsasy]

Just.. So.. Absolutely stunning.. One of the greatest jobs on earth that I would love to have..

[@Northstander]

OK, now I should start by saying that I am not a scientist, I didn't even take biology as an option at school. However, it struck me that the way the protein attaches itself to the ice crystals and stops them from growing could have an application in humans, if we could develop proteins that attach themselves to things like cancer cells and work in the same way to stop them multiplying and spreading. I am guessing that we have biologists working on stuff like this, and it is probably being done already, which could demonstrate a real World benefit to the human race of the work that is going on in Antarctica. Oh, and doesn't the young Art look like David Beckham?

[@chrism3562]

Glad SpaceTime sent me over here!

[@EXbobomb]

Could these antifreeze proteins be adapted to humans to survive in freezing temperatures?

[@mirunautlus]

intresting

[@rmod42]

Big up the spacetime massive!

[@charybdis9238]

Deep look sent me... Nice video btw XD

[@prabhatbhandari]

So Macklemore has become a biologist in Antarctica.

[@jcwdog]

Physics Girl sent me to see this video. Grateful she did. Amazing!

[@katiepollard794]

Great video! Thanks for the recommendation Two Cents 👍

[@Sherwoody]

I didn’t see any stickers on the tanks. Are you using regular air or nitrox when you are diving.

[@MOOAntarctica]

Just air on open circuit, though the Dive Supervisors are also approved to use rebreathers from time to time.

[@Sherwoody]

McMurdo Oceanographic Observatory thanks for the info. I’ve only dove under ice once and I felt uncomfortable the entire time. You guys rock.

[@jeffcupo4160]

This is such a really great series, love it!