Why Humans May Actually Be Fish

Is there a chance that more species may actually be closer to fish than we originally thought?
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Sources:
ucmp.berkeley.edu/clad/clad5....
evolution.berkeley.edu/fishey...
evolution.berkeley.edu/phylog...
www.britannica.com/animal/shark
www.brooklyn.cuny.edu/bc/ahp/C...
www.britannica.com/science/sp...
www.nationalgeographic.org/en...
www.britannica.com/animal/pri...
www.britannica.com/animal/fis...
www.britannica.com/animal/tet...
Image Sources:
Images and Videos Courtesy of Monterey Bay Aquarium
www.gettyimages.com/detail/ph...
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commons.wikimedia.org/wiki/Fi...
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www.gettyimages.com/detail/ph...
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en.wikipedia.org/wiki/File:Br...
www.eurekalert.org/multimedia...
www.gettyimages.com/detail/vi...
www.gettyimages.com/detail/ph...
commons.wikimedia.org/wiki/Fi...
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commons.wikimedia.org/wiki/Fi...
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www.gettyimages.com/detail/ph...

[@1BlueYoshi]

I remember hearing a funny story in a biology class once: Before we had the ability to analyze genes, we classified animals based on shape, like mentioned in the video. Well originally, all raptor birds were considered to be closely related and were put in a group together called "Falconiformes" (Falcon-shaped). Well eventually when we analyzed the genomes of the birds of prey, it turned out the we were right. Most raptor birds are in fact closely related to each other, with one notable exception: Falcons. Because of this, falcons were not originally in the "falcon-shaped" group. Classification is fun.

[@jaschabull2365]

At least Wikipedia seems to think everything but falcons got kicked out of Falconiformes, and most of the other raptors got put in Accipitrimorphae instead.

[@Drakowyn]

It's kinda the same with the Saurischia (lizard hipped) and Ornithischia (bird hipped) groups in dinosaurs. Saurischia have a hip structure that superficially resembles a lizard's while Ornithischia's resembles that of a bird. Yet birds are actually part of Saurischia and only later developed a structure similar to Ornithischia's.

[@migitri]

@@jaschabull2365 you (and Wikipedia) are correct. Per the South American Classification Committee, only Falconidae (falcons and caracaras) remained in Falconiformes based on Hackett et al.'s findings in 2008. Everything else (hawks, eagles, etc.) got moved to Accipitriformes.

[@petrfedor1851]

What is even wilder (to me at least) is Falcons are closely related do parrots and songbirds. And there were stem-parrots that basicly live as owls without being related.

[@1BlueYoshi]

@@migitri Ah ok thanks, it seems I missed the last part of that story. I still think it’s funny that doing that was necessary though. I edited the comment slightly to show that this is the case now

[@jaydubaic21]

If there’s one thing science has taught me it’s that we are all just fish aspiring to be crabs.

[@genghiskhan6809]

I see. So you too are a man of culture.

[@sythrus]

and all plants aspire to be trees, with the final, ultimate form of life being crab trees

[@ImmortalDestructor]

@@sythrus They have achieved this goal already, for the crab apple tree exists

[@sythrus]

@@ImmortalDestructor the ultimate life form indeed

[@Bunny-ns5ni]

@@ImmortalDestructor I'm dying

[@TJ-vh2ps]

“We use language in different ways, based on what is useful for that conversation.” This is true for all communication, but is especially critical to scientific communication. Scientific literacy starts with understanding that the same words can mean different things in different contexts. This is something that needs to be better understood in the general population. Spread the gospel Hank!

[@chrisn8349]

I need this as a poster.

[@jaschabull2365]

Just took a vertebrate zoology course this year, and I was told that the explanation at 3:03 was a misconception, and that actually all jaw-bearing species had ancestors with bony skeletons, but chondrichthyans underwent a secondary loss of bony skeletons (kind of like what happened to legs for snakes), likely to provide buoyancy to compensate for lack of a swim bladder (it seems to me a better name for Osteoichthyes would be Physichthyes, as the gas bladder seems to be their actual main derived characteristic). As for whether or not a beaver is a fish, I've decided the best answer would be that a beaver is as much of a fish as I am, and leave it at that.

[@torshavnnewell]

That last message is very profound. Thank you

[@akumaking1]

“Are we all just fish” sounds like a meme from the early 2010s

[@grrismellwaffles]

Birds aren't real

[@mastaw]

@@grrismellwaffles Neither is new zealand

[@EnigmaticLucas]

Sounds more like a meme from 2022. Early 2010s humor wasn’t really surrealist.

[@grayaj23]

South Park's Mr. Garrison was saying 'we're all just re*rded fish-squirrels" in the 2000's, so yeah

[@van4773]

@@EnigmaticLucas there was that one thinking velociraptor meme, it could apply to that one. But yeah, "dank" memes are pretty recent, the last 4-5 years or so, 2010 was all troll faces and Meme generators

[@Laff700]

As a fellow fish, I'm glad you're talking about our fishy nature.

[@sdfkjgh]

The fishy is sus. Reminds me of a Monty Python sketch were a bunch of mountaineers are yelling for more fish. "FISHY FISHY AI-O!"

[@richardwalker6004]

I’m related to a shark and you all can be related to the puny goldfish

[@raythegardener]

Oh God, I'm a cannibal.

[@nikhilPUD01]

Are we all just fish 🐟 finding Nemo!

[@pyropulseIXXI]

my imaginary girlfriend smells fishy

[@silverwurm]

It’s like the question “are tomatoes fruits or vegetables”. There’s a technical answer, and a practical answer

[@Dragoniiia]

Fruit in both. I don't understand in under what conditions would anyone call tomato a vegetable

[@andrewsuryali8540]

I kinda think this is a problem for European culture mostly. In Indonesia we call it buah tomat (tomato fruit) for the tomato on its own and sayur tomat (vegetables with tomato) when it's been processed as the base or soup for a vegetable dish.

[@silverwurm]

@@andrewsuryali8540 interesting. If my example was to be rewritten so it could be translated and make sense to an Indonesian audience, is there some other thing besides a tomato that would work? Something that is technically one category but in practice is another?

[@andrewsuryali8540]

@@silverwurm Whales. We call them ikan paus (whale fish). But then we end up with the question in this very video. Interestingly, some linguists believe that because our word for whale (paus) is also the same as our word for the Pope, ikan paus originally should have translated to Pope fish. It depends on which usage came first, and there is strong suspicion that paus as Pope was an earlier usage.

[@LeeSpork]

@@Dragoniiia Tomatoes are considered vegetables by nutritionists and for culinary uses.

[@zackakai5173]

Couple of useful definitions for anyone interested: - A monophyletic taxon (otherwise known as a clade) is any group that includes ALL its descendants and NO others. In order to be a valid clade, it must be monophyletic. - A paraphyletic taxon (not a valid clade) is any group that includes some of its descendants, but arbitrarily excludes some specific subset (like excluding tetrapods from fish). - A polyphyletic taxon (also not a valid clade) is any two or more groups that are said to be the same thing, but don't have a common ancestor that was also that thing (surprisingly common in the old Linnean taxonomic system, because convergent evolution is a thing and that system was based on morphology rather than phylogeny).

[@wiandryadiwasistio2062]

is this the case i was thinking about _Sansevieria/Dracaena?_ because i saw from multiple sources that those genera have rather multi-branched clade/genus that sparked drama throughout dracaena/sansevieria communities

[@Weirdisjustabrownandyellowword]

Wasp phylogeny is all over the place. It's polyphyletic with loads of paraphyletic groups in it. The definition of a wasp is basically any hymenopteran insect that is not specifically called something other than a wasp. At least hymenoptera's a clade.

[@theyeetmeister4019]

im so happy that a channel this large is finally talking about clades

[@bobrobe7121]

Couldn't get outdone by Sam O'nella

[@theyeetmeister4019]

@@bobrobe7121 I can't believe that mf just showed up like he wasn't gone for 3 years

[@theyeetmeister4019]

@@drstone3418 I wonder where they'll move the goalposts next

[@GameTimeWhy]

@@drstone3418 yeah "kinds" has always been super silly.

[@martinweiss2955]

Never heard the term before, but the genomic based concept is FAR superior to what an organism looks like.

[@seatbelttruck]

It kinda blew my mind when we first went over cladistics in college. The prof used birds as an example though. Reptilia is paraphyletic unless you lump Aves in there too, so by cladistic standards, birds are reptiles. (Also, crocodilians are more closely related to birds than to other traditional reptiles). In other only tangentially related news: I recently learned that domestic cats are more closely related to cheetahs than to bobcats.

[@seanpeacock4290]

considering what my cats get up to in the middle of the night I am not surprised.

[@EnigmaticLucas]

Not only are they reptiles, they’re also dinosaurs

[@AgentTasmania]

Your cats have tails and are descended from african wildcats, not American lynxes. Shouldn't be that surprising

[@BeckBeckGo]

@@AgentTasmania my cats have tales. But that’s mostly from living with me. Tails, on the other hand….

[@LaNina_DJ]

Well chickens are dinosaurs right?

[@delecti]

It seems like "non-tetrapod fish" is just as useful and succinct as "non-avian dinosaur", which is a term that gets used all the time.

[@GlorifiedGremlin]

Please never change that intro. It gives me so much nostalgia every time, I first found this channel damn near a decade ago when I was a kid

[@Kerbezena]

But the intro graphics changed a few times. Check out some older videos.

[@robertlackey5845]

I was pondering the bird/dinosaur classification recently and ultimately came up with the "we're all fish" headline as well. It's amazing what wine can accomplish.

[@sebasbot01]

birds are most definitely reptiles. fight me

[@mikacakes]

I'm in camp "fish don't exist" lol

[@Billybuckets]

That’s another easy one. Birds are dinosaurs. Dinosaurs didn’t go extinct. A lot did, but many didn’t.

[@ryandoyle3413]

As a wine scientist, it is indeed amazing what wine can accomplish!

[@timapple6586]

@@ryandoyle3413 Yeast makes us do its evil bidding.

[@gochadc]

Maybe the true fish are the friends we made along the way.

[@DrRiley01]

Finding Nemo taught us fish are friends, not food.

[@Havron]

The true fish were inside the fish all along.

[@alantremonti1381]

The real comment is always...in the...comments.

[@oravlaful]

true friends are the fish we made along the way

[@Merennulli]

On that note, it might be interesting to discuss the not-quite-animals-but-not-fungi in the Holozoa group. There's 5 main groups that I know of, and you frequently go through around 5 examples when doing your episodes on a subject, so it seemed like a good fit.

[@AllegedlyHuman]

I am intrigued but not inclined to look it up. May I ask for a portion of your knowledge, please?

[@Merennulli]

@@AllegedlyHuman I am guessing from this that you only want the broad strokes. Essentially eukaryotes break off into a few clades, one of which includes animals and fungi. That branches further into fungus-like and animal-like. The animal-like clade further branches, giving animals, and 5 different animal-like microbes.

[@AllegedlyHuman]

@@Merennulli thanks! And honestly, I wouldn't mind a deep-dive, but don't feel pressured

[@Merennulli]

@@AllegedlyHuman The most distant group, ichthyosporea...as the name implies, are spore-like creatures that are fish parasites. Corallochytrium is the next most distant from animals... and we don't 100% know what they are. They are colony cells found on coral reefs and they might eat bacteria. At the same distance is Syssomonas, which eat eukaryotes and have a flagellum to get around. Filasterea is the third most distant, with only 2 known species. A bacteria eater and one that lives on sea snails. Choanoflagellate is the closest and includes a bunch of single celled creatures with a single flagellum surrounded by a collar that kind of looks like the cone you put on dogs to keep them from licking themselves.

[@AllegedlyHuman]

@@Merennulli man, that's really interesting! Thanks a bunch for sharing!

[@relay6109]

Definitely option 3. Fish is way too general. Everything started in the ocean, so it makes intuitive sense that some of those branches will be further up than whatever crawled out onto land.

[@isaacbruner65]

Calling something an animal a fish is like calling a plant a tree. Trees are not all closely related to each other and have evolved numerous times. Palm trees are closer to grasses than to pine trees. Tree is a meaningless term, taxonomically. But it's still a useful one for humans.

[@Lexivor]

@@isaacbruner65 Not really true though, fish excluding tetrapods is a paraphyletic taxon, whereas since the tree phonotype evolved many times, it is a polyphyletic taxon.

[@yomiseno]

It does exist scientifically, because fishes have similarities. But maybe in that realm, they aren't able to place it on a category.

[@yomiseno]

Marine physical traits is what makes something "a fish" abd they probably dont have it there because of the basis of categorization. What is it about????

[@DallenRex]

I've always really like the phylogenetic and cladistic categorization because it feels a lot more explanatory and connecting than just semi-arbitrary categories. It's more about how things came to be, which is more of a story and easier to remember for me. It does definitely lead to some awkward language needed to identify some specific groups, though.

[@spindash64]

Same. It’s just the logical order to match things up in. In addition, it’s usually a better measure of “under-the-hood” similarities, which are more important biologically much of the time than surface level things. For example, we consider it more important to call Dolphins Tetrapods than to group them with everything that swims, because the act of swimming is not as critical in “how do you not die?” As the function of getting oxygen to metabolize, and Dolphins, like all tetropods, primarily due this thru Lungs, not Gills This is just a more consistent approach to the problem

[@DallenRex]

Yeah, and it lets you make inferences about other animals in a clade, because they're genuinely related and not just apparently similar.

[@MenaceLendil]

Those semi-arbitrary cathegories skin can be usefull in science when non discussing evolution. Sometimes you don't actually care whether organisms are closely related it's the outward traits that matter. In the microbial world taxonomy is a mess and still in the process of constant changes plus horizontal gene transfer complicates the issue. So it's often more usefull to reffer to bacterial strains by the traits they exhibitic rather then genetic relatedness.

[@ommin202]

It feels like the difference between imperial and metric measurement. One is more useful for everyday life, and one is more useful to higher education and specifics. Same with Celsius and Fahrenheit too!

[@fernandoc4741]

What is the purpose of using the word fish, for things people call Sharks, Ray, Lampreys or Lungfish? It would not be easier to call fish just the ray-finned that people usually call fish? I ve never Heard someone saying look there are dangerouus fish on this sea, people just say sharks. On the other hand we have fish and chips, fishing and many other words using fish as an thing not as an category. It is a concrete word like bird, snake, bacteria not an abstract one like mammal, primate or amphibian.

[@davetoms1]

This is "planets don't exist" all over again I love this kind of realization and Hank's awful puns lol

[@willz7369]

+1

[@chillsahoy2640]

It's a humbling reminder that the universe is big and complex, and our brains evolved to solve a certain type of problem, but we've been using them to try and solve/understand entirely different questions. So it isn't surprising when we end up not being able to create neat categories that seem sensible to us in an intuitive way. It's just like someone trying to understand why the laryngeal nerve in giraffes takes such an inefficient and needlessly long route: from an engineering perspective it's absolute rubbish, but from an evolutionary perspective you can see why it evolved this way.

[@StraveTube]

No Edge

[@markykid8760]

Have you heard the ones on PBS Eons videos? (smh) Hank's ones actually worked! 🏅

[@chrisn8349]

@chillsahoy2640 I read this fact in Human Errors but I keep thinking about Good Enough that has a giraffe on the cover.

[@rebelappliance771]

The fact that all vertebrate tetrapods are derived from fish begs the question if some of the traits that make humans what we are (I.e, our creativity and perseverance) first originated in fish, especially if more complex thought started with them.

[@terramater]

That's so interesting! Our crew filmed babirusas, which split from other pigs between 22 and 13 million years ago! But still, if you look at evolution, pigs are related to moose, camels and even hippos! Who would have guessed that?!

[@AngelEmfrbl]

And with that note, the hippo being the closet relative to Dolphins and whales...

[@reeyees50]

Everyone would have guessed it. They are even toed ungulates. Aka, the number of digits in their feet give us a hint

[@llsilvertail561]

Goldfish are more closely related to us than they are to hagfish and I love it

[@Programm4r]

We share similarities to fish, but we are NOT related to them.

[@warsamek8275]

@@Programm4r we are

[@Programm4r]

@@warsamek8275 religious. Otherwise, prove it

[@anna.owo.]

​@@Programm4r dna, is not hard to understand

[@Programm4r]

@@anna.owo. nutrition science 101: if you don’t share DNA with it, you can’t metabolize it. That’s how it works.

[@leslieviljoen]

Shout out to the hilarious "No Such Thing As A Fish" podcast - the researchers for Stephen Fry's "QI" show and their crazy facts.

[@VillSix]

I was looking for a no such thing as a fish reference. thanks!

[@mattgough3856]

Beat me to ut

[@916oh2panther2]

Thank you for this easy to understand description. I've been listening to the "no such thing as a fish" podcast but I had no idea what they meant with the title.

[@zorgus2002]

Thank you Hank. I am proud to be a fish.

[@samanthaecotothermia7896]

"Humans are just derived fish." - My evolution professor, back in the day Also, I adore the thumbnail

[@wafikiri_]

Clades are useful, but even more useful are clades with exceptions. Even neurons use this system of exceptions, that's why there are inhibitory synapses outside the regulatory kind that surrounds axon hillocks. "But Not" is a very powerful logic operation that helps a lot. I wish search engines had this clause to filter out lots of unuseful, unwanted results. Whatever I've tried, it hasn't worked.

[@LionsInBoots]

a fish is a primarily underwater vertebrate, that doesn‘t possess proper limbs. there‘s probably a few exceptions but I think that rule is the most accurate we could get

[@anna.owo.]

Define proper limbs, is that based on human limbs?

[@MusicalRaichu]

The problem with classifying according to descent is that our knowledge is incomplete and will likely always be so. Plus we have to reclassify each time new evidence forces us to change our minds. Classifying according to observable and testable features (like does it have gills, lungs, stomates, etc.) might tell you little about how it evolved, but it lets you classify and identify specimens definitively.

[@kts8900]

The Monterey bay aquarium has amazing live cams. Also, the book "Why fish don't exist" is lovely.

[@chrisn8349]

I'm reading this book right now!

[@Niinkai]

The fish was within us all along!

[@callmeperch]

The ultinate collab!! I love both of these channels, so happy right now!

[@karencrawford4068]

I love smart people who can play with words and find humor in pronunciations that vary here and there. Makes me smile! Thanks Mr. Green

[@jaydonbooth4042]

Very interesting, I've wondered about this recently learning about taxonomy and classification. I'm glad you made it clear it's still fine to call a fish a fish, just not as a scientific category.

[@123890antonioj]

Same as with Pluto; isn't classified as a planet no more, but we can still call it Pluto. The full minor planet designation seems cooler though (134340 Pluto) In a recent vlogbrothers video, Hank also gives an explanation on how the classification of "Planets" might not be too meaningful(like fish), especially when considering other solar systems. (Edit: of course everyone else already pointed at that video lol)

[@juliandacosta6841]

@@123890antonioj while pluto isn't a classical planet, isn't it still a toy planet, or a dwarf planet?

[@catpoke9557]

@@juliandacosta6841 For some reason, even though "planet" is in the name, dwarf planets are not considered a type of planet. Supposedly for scientific reasons, but in reality it's clear this definition was made specifically to exclude Pluto because if it was a planet we'd have hundreds of planets in our solar system as well by default. Personally I think we should just divide it into the "major planets" and the "minor planets." All the objects we consider planets now get to be major, then dwarf planets get to be considered planets, but minor, so they can have their clean and tiny textbooks like they wanted. Don't want to list a ton of planets? Just skip the minor ones and go over the major ones.

[@juliandacosta6841]

@@catpoke9557 the system was also created for things like eris

[@jorgiederosa6440]

God i hope someone from the podcast No Such Thing As A Fish sees this. If anyone has twitter please can you send it to them!

[@Ewr42]

i tweeted it and tagged them, hopefully they'll see it

[@Booksds]

At least, we can send it to everyone except Anna 😂

[@ericbrock4340]

I believe I saw on a different KZbin video that the argument that "Beaver are fish" was applied in South America to have capybara also listed as fish for the purpose of Catholic Lent.

[@StarCrusher.]

This episode was especially well written and narrated by Hank. Real fun stuff!

[@ADruid25]

It is actually kinda fascinating (and funny) the wide variety of thing that where classified as fish, for the purpose of Lent. Pretty much if it lived primarily in the water and didn't kill you upon eating it, at one point or another it was classified as a fish

[@svennoren9047]

Being scaly was also a good sign, and beavers have scaly tails. On the other hand that excludes crayfish, so...

[@robinhahnsopran]

Heard about this episode from the recent Tangents podcast. Hank was SO excited about this one - and it's so justified! 👏

[@kimbratton9620]

SciShow never fails to amaze me!

[@zack-nl4gr]

So this means that modern birds are dinosaurs too by this cladistic definition. Very interesting!

[@isaacbruner65]

Yes, modern birds being dinosaurs is actually a much more widely accepted idea by the scientific community and the public at large than humans being fish. That's why paleontologists talk about "the extinction of the non-avian dinosaurs".

[@Programm4r]

Modern birds aren’t really dinosaurs. They definitely share similarities. Everything between is simply conclusion influenced by Darwin. I, for one, take it with a grain of salt.

[@nariu7times328]

I'm in my 50s and it is really fun to see the changes in Science, just in my lifetime.

[@TheJohn8765]

Same. Genomic sequencing has also vastly added to a bunch of bio fields (and chem and to a lesser extent phys). Hell, you can go dig in your garden with a spade and find a brand new species of rotifers (etc) every time you touch the dirt. Amazing!

[@icollectstories5702]

Science can learn and adapt to new information regimes.

[@pyropulseIXXI]

I'm 10, and there have been numerous changes to science in my lifetime alone

[@clogs4956]

“…the Librarian likes bananas, sir.” “Very nourishin’ fruit, Mr Stibbons.” “Yes, sir. Although, funnily enough, it’s not actually a fruit, sir.” “Really?” “Yes, sir. Botanically, it’s a type of fish, sir. According to my theory, it’s cladistically associated with the Krullian pipefish, sir, which I of course is also yellow and goes around in bunches or shoals.” “And lives in trees?” “Well, not usually, sir. The banana is obviously exploiting a new niche.” “Good heavens, really? It’s a funny thing, but I’ve never much liked bananas and I’ve always been a bit suspicious of fish, too. That’d explain it.” Sir Terry Pratchett, Hogfather.

[@Reyma777]

I had a biology exam Where I had to give a definition of what a fish was. I wrote something a kin to “ A fish is a craniate vertebrae that usually has fins, gills, and scaled skin. Fish usually lay eggs in water and generally spend most or all their life in aquatic environments.” I got 3 of 3 marks.

[@Weirdisjustabrownandyellowword]

Here's my definition: Any chordate in the class agnatha, a group of vertebrates that includes all descendents of the common ancestor of the majority of pelagic vertebrates, except for the descendents of the Devonian fish tiktaalik, the common ancestor of tetrapodomorphs, which diverged into several separate classes within the phylum chordata. All fish live in water, and can breathe using gills. Some species of fish can breathe air, but most cannot. Fish have fins for swimming and their skin is covered in scales, which are protective, overlapping keratin structures. Most fish have a swim bladder, which provides bouyancy in the water. Most fish are pelagic, having retained the ability to swim from their common ancestor. Fish reproduce by laying eggs in the water. They can inhabit both marine and freshwater environments, with some species inhabiting both.

[@pyromaniac000000]

Monteray bay aquarium? Hell yeah, Rosa is great, shoutout to all of us Rosa lovers from the DougDoug community. The best otter to ever live, hands down lol

[@rileystine8970]

"Why Fish Don't Exist" by Lulu Miller is a great book on this!

[@ellingtonlilly]

Oh man! My art school curriculum typo was accidentally right! Fish are fantasy creatures!! Haha! The world is ridiculous 😄

[@alphazygma]

I love the Monterey Bay Aquarium, been a member for many years now. Love the partnership in this episode!!!

[@mixmastermike2128]

I SAW THIS ON YOUR TIKTOK HANK!! LOVE THE STUFF!!

[@MRptwrench]

Reminds of when my older brother and I argued the night we saw "Jaws" in the drive-in. Summer of '75, while we were down the Jersey Shore. Big bro acting all cool, "real scary, a big fish" (as big brother, he was fan of The Exorcist and Rosemary's Baby) and I sh0outed him down "Duh stupid, it's a Shark, not a fish!" My father put an end to the argument. "Shark, fish, what's the difference when it's bigger than the boat!"

[@AkiyamaKatsuko]

We would also count as microbial life if you go back far enough.

[@TacticusPrime]

I think we just have to call "microbes" a non-cladistic group. There are so many tiny tiny things that are less related to each other than we are to amoeba.

[@SunroseStudios]

@@TacticusPrime yeah i think "microbe" as a definition is mostly just "organisms where an individual is too small to see with the naked eye"

[@massimookissed1023]

I think we've evolved into macrobes at this point.

[@sporksto4372]

@@TacticusPrime That's called a paraphyletic group or a clade.

[@mathewfinch]

Humans are just a very specialized colony of eukaryotic bacteria.

[@geologyjoerocks]

I was JUST talking about this in my class! Great timing!!!

[@andyjay729]

Reminds me of the debate about how either birds are reptiles (crocodiles are actually closer related to them than to lizards), or Reptilia should be split up.

[@_mortiam]

Monterey Bay Aquarium: How many puns can you put in one sentence? Hank: YES

[@relucentsandman6447]

I was not ready for this, it is both hilarious and amazing

[@hunterwayne7112]

Ya got me on TikTok, and you earned a follow. You make great content

[@marcopohl4875]

A possible solution to this that I came up with: you could exclude anything closely related to land vertebrates (lungfish, lobefinned fish, etc) from fish and give them their own clade, protopoda maybe. Not sure if that would work.

[@satanofficial3902]

Fun fact... "fish" spelled backwards is "hsif". Which explains so much.

[@coconutcore]

YEEEEES! FINALLY TACKLING THE IMPORTANT ISSUES! I’ve been thinking about this for ages. Edit: I would like to tank the Monterey Bay Aquarium for this. It was VERY finteresting findeed.

[@birbman5186]

HANK I didn't even know you had another Channel! I used to LOVE your Biology and History lessons back in highschool and helped me matriculate with an 80% pass! I'm so glad I get to actually watch your content for fun now, now that I'm a tertiary student.

[@demonac]

This "fish issue" should definitely be called "the Fissue"

[@MarinoHorvat]

It is a dad joke, but damn they missed a opportunity...

[@ayush21399]

Quality content, every time I learn something new from here.. 10/10

[@alien9279]

The first real hanklerfish has been spotted and captured for today's thumbnail!!

[@RazorBaze]

05:41 monterey bay aquarium proposition was brilliant :D

[@jakobraahauge7299]

aww! Hank is such a delightfully wholesome guy!

[@lucasmendoza7576]

Fascinating, do you think you could do an episode on the cladistics of crustaceans, I have heard they are acutally not monophyletic and I was wondering if you could cover that topic.

[@SpikedHairVSGravity]

All protostome cladistics are wild

[@CorbiniteVids]

Yup! If we were to make crustaceans monophyletic, that makes insects a kind of crustacean

[@sdfkjgh]

Everything becomes crab. Welcome to the Crab Cycle: There is only one step *AND IT IS CRAB!*

[@toddbod94]

@@CorbiniteVids everything with an exoskeleton is a crab.

[@SimonClarkstone]

@@toddbod94 as was alluded to above, crustaceans keep re-inventing the "crab" shape from different ancestors. It has evolved like 12 times.

[@AlvarM]

I was recently wondering about the usefulness of calling something a fish. I was about to ask Hank via TikTok. Glad to get an answer? 😂

[@nasry1445]

bro was telepathic 💀

[@micameows]

whoever did the thumbnail for this one’s a genius

[@__-ln7sb]

brb making fish hank yt account

[@whtiequillBj]

I was hoping for a longer video explaining the advantages and disadvantages of cladistics vs phylogeny vs taxonomy

[@Temp0raryName]

Well I am planning on having fish and chips tomorrow. But now that makes me worry that I might be a cannibal!

[@BonaparteBardithion]

It's only cannibalism if you eat the same species. As long as you eat any non-human species you're okay. So, enjoy your vertebrate and chips.

[@pedroff_1]

The version I had heard on the whole Catholic Churc and lent thing was on Capibaras, not beavers, but I wouldn't put it past them to have done it twice

[@michaelmicek]

In Louisiana, alligator counts. The idea is that you have to abstain from meat rich people grow to eat; stuff that a poor person would grub up to survive is going to be okay.

[@BonaparteBardithion]

My understanding was that they reinterpreted fish to be whatever protein source was readily available to trappers and settlers, at least as far as beavers go and I assume the same applies to capybara and gators. Another comment mentioned sailors eating penguin. The exceptions did seem to focus mostly on animals that lived at least part time in the water to justify it.

[@conure3029]

i have never heard of the Devonian having the “Age of Fishes”, but I’m absolutely delighted by it

[@CatBarefield]

The thumbnail. The PUNS 😂😂 you are killing me

[@varsityomega]

Finally! I've been saying that we're all walking, talking fish for years!

[@Laff700]

Same, I just sent this video to my family lol.

[@Dasycottus]

As a fish biologist teaching evolution, I couldn't be happier to see this 🤩🐟 P.S.: Sarcopterygian squad fall innnnn

[@sachiel197]

Hey I actually know a similar case to this! it's about the clade Lepidoptera moths are not a monophyletic group, because butterflies are technically a subgroup of moth so either they are also moths, or moths as a category don't exist

[@fmarquaire]

I would recommend a very appropriate podcast channel for lovers of this video: No Such Thing as a Fish! They’re awesome

[@marielozoria]

I read “why fish don’t exist” earlier this year and I definitely understood the concept but I have trouble replicating the basic definition myself. So if anyone asks me what the book is about, I’ll point them here!

[@Bowie_E]

Neil Shubin has an excellent documentary on how we are just fish... I think it's called Your Inner Fish 🐠

[@bugguyonline]

awesome

[@emm6064]

It's a book too. Explains everything from hangovers to hiccups!

[@Bowie_E]

@@emm6064 oh nice, I didn't know that! Thank you 🤗 🙌

[@AndreaCrisp]

So cool. Thanks for sharing! Science is wild! I love MBARI and watching the ROV footage. Question - When did Clades become the common way of talking about organisms? Because I never learned this in school. Is this only college level science/biology? Or is this now taught instead of or along side the Kingdom, Phlylum, Class, Order, Family, Genus, Species? DNA was hot when I was in college, but it wasn't until after I graduated that the human genome was sequenced. I'm thinking Clades are probably only talked about in more advanced schooling, not with kids. But since I don't have children I don't actually know what they teach now...

[@mrainbowgs]

I believe a big part of why the beaver was accepted as a lent meal is its scales. The beaver has a scaly tail and scales normally being assosiated with fish did the trick.

[@SilverScarletSpider]

i am fish. and i am proud to be fish. we will no longer sit in silence inside a closet. #fishypride

[@straps-of-skin]

Im proud of my fish ancestry. Thanks for slowly morphing into me! I like it here 👍

[@Tesserex]

Slight mistake at 4:03, tetrapods are lobe finned fish (sarcopterygii), not a sister clade of them.

[@jessicaromo4369]

I always think it's cool when they partner up with MBA. While it's not the same city, it's in the area and have been there multiple times. Beautiful place to visit.

[@zxzxzzxx7396]

By the way, how much is the fish?

[@bugguyonline]

200 thousand

[@glenngriffon8032]

Wow talk about a callback

[@maturepopcorn]

I wish I was a fish. Such a simpler life…

[@bugguyonline]

ok but u get eaten by bear 😔

[@maturepopcorn]

@@bugguyonline Sounds like a cool way to go out

[@kirkmorrison6131]

I wish I was my dog she is so pampered

[@oiltoast3723]

Trust me being a fish is quite boring you'll have to find fun and it's difficult to do.

[@Iscannon]

Best thumbnail in the history of scishow

[@dailyStoic641]

Finally! someone who’s asking the real questions

[@NemoVonFish]

Okay hang on, but if you're saying beavers are fish, that means I can eat human flesh for lent. Thanks, Hank!

[@invisiblepants6477]

Even if I'm not technically a fish, I still identify as a fish.

[@jtjames79]

I identify as a bigger fish. Checkmate.

[@bugguyonline]

@@jtjames79 i am a bear, i eat you 😂

[@mastaw]

But technically you are a fish

[@mastaw]

@@jtjames79 I got to fry you

[@SunroseStudios]

nothin wrong with that

[@bunnygirl2448]

This reminds me of how, as a kid, my zoo used to have a “pachyderm house.” It included rhinos, hippos, elephants, and tapirs. Now we know most of these animals couldn’t be more unrelated in the evolutionary family tree.

[@J.A.Smith2397]

Great one

[@MadDragon75]

Fintersting? 😆

[@bugguyonline]

LOL

[@MadDragon75]

Monterey Bay Aquarium is just the next county north of me. Ask Dory. 😆

[@ESLTopics]

So ... does this mean I can eat humans during Lent? 🤔

[@marietailor3100]

Omg. This feels like Hank was taking his vlogbrothers video from last week about planets to the next level lol😂

[@KayossPlays]

Okay this man must be John green's brother? I thought it was him and that he'd taken a step sideways from lit... then checked his name and it would just make too much sense. Love both of their videos!

[@kafuuchino3236]

I think the "all vertebrates except tetrapods" definition is fine, tbh! It's paraphyletic, sure, but it's still a useful category when talking about, say, the physiology or ecology of fish and how they differ from land vertebrates. It's not a clade, but cladistics is one way to look at the natural world, not the only way!

[@MrCmon113]

Whales are fish.

[@servantofaeie1569]

What I got from this video: either the teacher was wrong about whales and dolphins not being fish, or was wrong about sharks being fish.

[@yeuxdal]

Ok that’s the FIRST ever sign-off pun on any PBS channel that actually made me laugh

[@BrotherAlpha]

I tried to explain this to someone and how we are technically more closely related to salmon than salmon are related to sharks. They called me a creationist.