How These Animals Lost Their Heads (And Bodies, and Butts)
You'd think that there are some features that, once an animal group evolved to have them, could never really go away, right? Well, Stefan is joined today by hosts from PBS Eons, Journey To The Microcosmos, and Bizarre Beasts to break down just how wrong that is! And yes, we will be talking about tardigrades.
Eons: / @eons
Journey to the Microcosmos: / @journeytomicro
Bizarre Beasts: / @bizarrebeasts
Hosted by: Stefan Chin (he/him)
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Sources & Image Sources: drive.google.com/file/d/1k1OP...
...so no head?
[Tartagrades has entered the chat]
I understood that reference. *Proceeds to stomp on a skateboard*
I didn't even watch the video, I just ran straight to the comments SPECIFICALLY for this!
No head 😢
Sometimes you just want to get down to business😉
I gotta say I'm absolutely loving the refreshed style on scishow, it's great and the slightly longer videos and new hosts are great too!
They couldn't stand much longer, now that they have chairs they can do 15 minute episodes 😂
Very much same. Very cool. Much more laid back. Love it.
It's my favorite clown show
same, i love how comfy the new living room background makes the videos look!
I’m happy for the people who are happy, but to be honest, I miss the more frenetic, energetic style.
As a geology student, putting the line of symmetry down the middle of the bivalve instead of inbetween the shells hurts me a little bit, because its the main way we distinguish between bivalves and brachiopods
THANK YOU i was like how did u not split it the most obvious way
Especially since scallops are the only ones symmetrical along that axis. Mussels, oysters, and a lot of clams certainly aren’t. Of course, it doesn’t help that oysters and many scallops are not completely symmetrical between the valves, either, at least their shells aren’t.
I mean, brachiopods have holes in the shell. I’d think that’s a pretty easy way to distinguish them.
Can you explain the geology aspect of your comment? I feel like I'm missing the connection.
@@ajchapeliere I'm talking about in fossil specimens (there are much easier ways to tell in living ones), and I know in some other places Palaeontology is considered completely separate, but in the UK its a subset of Geology
Im liking the new style guys. The small mix of comedy into the knowledge is not only refreshing, as a science nerd I feel like it helps people who are here learning for the first time feel more comfortable and open to learning. So keep it up guys! Y'all are a great channel.
What a fun crossover! Seems like Complexly is digging into more complexity with production!
stefan got comfy on his couch and summoned 3 juniors to take over xD
A lot of people I’ve encountered never really progressed past the early stages of being a deuterostome.
Ya...They are also know as Republicans.
@ArchFundy Don’t bring politics to Scishow, please!! Even though I agree with you lolll
Some i know are multi-butts!
This coming from a starfish lefty...
Huur hurr hurr a joke like that's never made before
Dude, that starfish thumbnail was already great. This headless rhino is just macabre.
It's likely been both the whole time. KZhead has a new feature for creators where they can upload two thumbnails and KZhead will show both of them, depending on which they think that specific user (you) will click on. It can also change between the two if you've not watched the video and the algorithm has updated data that shows similar users responded to the other pic.
It reminds me of a cartoon by James Thurber, who was going blind at the time. He was going to draw a sofa with a couple sitting on it but ended up with a rhino with its head turned.
@@SavageMinnow Good to know.
@@sophierobinson2738 this is a tiny part of a person’s story I never would have thought to learn. The world is bafflingly big
"Multi-armed head" brought back memories of John Carpenter's The Thing. Evolution was a bit faster in this case though.
Thats a parasite mutating their host (changing phenotype/ physiology). I would not call it evolution. Also it was a great practical effects horror / thriller movie :D
Really? That description brings Krang and Utroms to my mind instantly.
i was thinking of Davy Jones from the pirates of the caribbean
@@kleinerprinz99 It's shown killing other lifeforms and mimicking them, not infecting hosts. We might speculate that it is a parasitoid though.
@@alveolate Did he poop out the top of his head too?
I remember hearing or reading about certain tube worms that have no digestive system. Not even a mouth or anus. They live near volcanic thermal vents and absorb nutrients straight through their skin.
😮😮😮😮😮
If memory serves, Don't they have bacteria growing within them, that consume the nutrients before being digested by the tube worms?
@@rateeightx Close. I looked it up, they don't actually digest the bacteria; they form a symbiosis. The tube worm provides the bacteria hydrogen sulfide and a safe home and in turn the bacteria produces food for the tube worm which, I suppose, just enters the bloodstream. oceanexplorer.noaa.gov/explorations/02mexico/background/tubeworms/tubeworms.html Sometimes real life is stranger than science fiction.
I always assumed that molluscs _with_ heads and molluscs _without_ heads evolved from a common, headless ancestor. Learn something new every day.
'Attack of The Ambulatory Head' - In theaters this Summer.
A few years ago I saw an old black and white movie, "The Crawling Eye". It's comedically bad
@@BionicMilkaholicThe one with the invisible flying brains got me. (They were visible under certain circumstances.)
For a lot of sea creatures, those ambulatory heads are terrifying. Do you know how starfish eat?
I think the number one thing I’ve learned from this episode is that I never want to step into the ocean ever again.
Maybe do a little wading, but any farther….No!
The deadliest thing in the ocean, by far, is the water.
@@sophierobinson2738 You hear people argue a lot about row versus wade these days, but I think it all depends on how deep the water is.
I was expecting to see tunicates on the list. They are some of the first chordates diverge from the rest of us. Their larval form is basically a free swimming fish, but when they mature they metamorphosize into basically a sea sponge and lose the ability to move, their heads and limbs, and most of their nervous system.
I was thinking about that too.
The new format is wayyy more entertaining, may the algorithm gods bless Scishow!
I already knew that echinoderms are deuterostomes, but it's still wild to me that we have more in common with them (evolutionarily) than we do with insects.
Loving the recent crossovers on the SciShow main channel. I was unaware there were more than just the SciShow spinoffs under the same company and am glad to know more now :)
Dude I love PBS eons. They're so cool.
A curse upon your thumbnail!
Im glad Scishow can still conjure up Great and Original Videos after so many years! I love to see the hosts interact like that. Very funny 😊
in re. tardigrades and minified body plans, parasitic wasps (megaphragma mymaripenne, for instance) have impressively /scrunched themselves down/
I'm going to accept this as my most-wanted Bizarre Beasts episode for tardigrades
It is so sad that this is the last year of Journy to the Microcosmos.
Seriously? Why?
Stefan's acting in this was great. The personality in the script is also really good and refreshing.
I love this collaboration so much ❣️ We definitely need more mashups between the completely channels!
I enjoyed and would love to see more episodes of Bizarre Sci Cosmo Eon Show
+
6:15 never seen that in my life but immediately makes sense that’s the water bears cousin with his cute little feet.
Im really enjoying the laid-back atmosphere at scishow and todays episode was an awesome collab of 4 of the best channels. ❤
I've never had such a strong feeling of joy accompanied by such a strong thought of "these guys are dorks," please never change, it's delightful
it's the cambrian explosion
The sun is a deadly lazer
6:09 aww why is it so cute
Wow, all three are disturbing in the best of ways. Thank you all!!!
I know there's debates about where sponges fit into the animal tree, where depending on what's right could mean that sponges lost a *lot*
Loved this collab (and the newer change in content format in general). I didn't know about all of those sister channels, so I love being introduced to more amazing content.
great colab! very interesting stuff, thank you :)
The wandering head idea reminds me of the one type of vampire which looks human by day, but by night its ears turn into wings and the head flies around looking for a meal.
Kipling: If you can keep your head ... Bivalves: No thanks!
This cross over is so fun!
Each of your videos generally prompts a flurry of wikipedia-browsing in me, leading me off on many diverse tangents and fascinating side quests. And people wonder why my head is stuffed with the most obscure and esoteric knowledge from all kinds of disciplines...
4:07 Oh wow I never knew about those eyes. That's strangely terrifying to me.
So no head?
*breaks skateboard*
loving the collabs ♡♡ always excited to find a new sister channel to follow!
You're right, "how animals lost their bodies" wouldn't sound right, perfect title as always
And now, "happy as a clam" maybe come back in full force!😂🎉 Great crossover!❤
I want four more brains.
What a mash up. All my favorite channels. On one episode 😍
These episodes keep getting better and better! Whatever you guys are doing, keep doing it. I LOVE all your channels.
woahhh i've never been this early to an upload !
Good to see Eons here! A big fan of it! Also good to see a Collab between some of my favorite channels!
Evolution is all about survival of the sufficiently fit.
Survival of the doesn't need to work out.
I can't believe they chose this grotesque thumbnail over the starfish.
"Being a bivalve sounds pretty chill." Yea, until you find yourself at THE OYSTER BAR!
Doesn't mermaids eat them too?
Oh hey Kallie, be watching that channel later😂
You know its gonna get crazy when the video starts with a definition of what a head is.
Really like that the sister channels get to have a get together to feature in one video, getting some of the attention they deserve as well.
Great show!
Nice collaboration
I'm so glad they're finally letting you guys sit down after all those years trapped in the scishow studio
The most mysterious part of the video was what you mean by an animal losing its body. First I thought: "Are we talking about ghosts now??"
Same, I still don't know what they meant, they defined a head but not a body.
@@AidanRatnage I suspect they meant something like torso, rump or upper body, but I'm not entirely certain. And you're right, I didn't even realize they defined what a head is, even though that one is much less ambiguous
Point of order: The diagram dividing the scallop shell into "left" and "right halves is incorrect. Bivalves are organized such that each valve ("shell") is on either the right or left side of the animal, not the top and bottom as seems obvious from looking at how most of them orient themselves. Most of them are, in fact, lying on their sides😊
True. But brachiopods have that one tho. But they are something completely different.
@@turkoositerapsidi Yep. But they're such an obscure phylum I didn't think I'd need to mention them🤪
@@scibear9944 You didn't need, but I wanted to. 🙂
I love the way sci show presentation style has Evolved. :).
I was JUST hoping for another PBS Eons episode… and then the crossover happened!!!
I love a good crossover!!❤
A long time ago I saw a story about a chicken that lost its head and lived a a pet for quite a while
Cool format! Neat to see other hosts/channels featured.
Really love this episode format❤
I really love the new set. Sitting down presenting is a lot nicer actually!
The plane of symmetry of the bivalve seems wrong at 1:54... Great video though!
Yeah
(eagerly raises hand) Ooh ooh ooh!! As I read the title and listen to the intro, I'm hoping they'd bring up sea squirts! I'm still in awe of how they're supposedly more closely related to us than a lancelet, implying that a free swimming chordate at some point found it more advantageous to stick its head into a surface transforming their adult stage into something that we may easily mistake for a sponge or sessile cnidarian
Barnacles found it advantageous to stick their heads to a surface as well. I wonder how many other times that's happened?
I thought this was going to be about Mike the Headless Chicken.
Such a good vid!
Love the new look and format
I’m geeking out at this cross over, I watch all of these channels religiously 😂
I loved the intro! Wonderful little skit :D
I just love how much genetic research has been done on species since I started watching documentaries on TV as a kid. There's so much new information that I keep finding out about every year now.
I saw this title and was like _please talk about the new starfish discoveries._ Happy to see that you did! :D
Avengers level crossover from all of my favorite channels. Genuinely made me smile. Thanks for this!
Multiarmed head for the win. xD Love the collab.
Loved the video as always!! may I ask what is the first song that plays?
10:16 That must definitely be the inspiration for Patrick Star :D Even the scientific name is similar.
Seeing Callie in the thumbnail, immediately watches video
They just changed it, but I agree though, lol
@@marilynlucero9363 I am sofa king grateful for your comment; I thought I was losing my mind! I could have sworn I saw something different a moment ago! 😂
That’s a headless rhino Bro
@@jeaniebird999 it's the KZhead meta now, they will have 2 or 3 thumbnails and swap them out in the first hour to see what pulls the most engagement
I thought we were calling someone a headless rhino. Was harsh bro haha
nah y'all KNEW what y'all were doin' with the caption on the thumbnail LOLLL 😂
That premise! 🤣Well done! 👍
an example of this type of body plan change i recently learned about is the subphylum Myxozoa! They're cnidarians that have opted into parasitism so strongly that theyre only a few cells large- some are even unicellular, and one species *doesnt even have any mitochondria.* As far as "animals evolving to lose things you'd think theyd like to keep, i think they deserve top billing for just deciding to leave this "being an animal" thing behind
very cute light humor in the beginning of the video :D
This was a cool mashup of channels. Doing a show like this every few months would be a great way to cross promote.
This is fantastic
bivalve life sounds sweet, where do i sign up?
So tardi grades found a genetic way to become chibi versions of themselves
Come to think of it, WHY is it that our sensory systems and our central processing facility are collocated? Sure, there are a whole lot of good evolutionary arguments like sensory organs requiring lots of nerves, short neural paths to the central brain and such, but there is a definite survival advantage to remote sensing facilities at the extremities and a well protected central brain in the body center. Just imagine a soldier being shot in the head, turning to his squad mates saying, "Sniper is on the left, behind the burned-out truck. Also, ouch, medic! Somebody else can stick their sensor pod out next, I've only three left as it is"
this is a cool collab of the major Complexly channels!
We need to do that genetic test on sea lillies (or whatever it is the few living crinoids are called). If their root and stalk are the trunk, which the starfish are thought to have lost when the groups split, it would explain where their bodies went!
Butt, no-body is arguing that these animals sacrificed too much to get a-head of the game!
thanks for the crossover episode
I'm liking the new aesthetics.
oh wow i was just watching old hank stuff and had no clue this was a new upload
Oooh does this mean we might get a feature of Matt from SpaceTime, too? I like the idea of rolling some of the extended PBS/Hankiverse together like this. Might be good for boosting viewership on the various channels too. Wouldn't mind seeing Dr. Becky featured either, but I'm biased lol.
I loved this episode
What a classy collaboration. This crossover felt like 2012 all over again when the Avengers have assembled. Shame for the inaccuracies...
One of these days, you guys are gonna have to do a video on Dendrogaster
There's also an example that's lost even more. There is a type of jellyfish that has evolved back into a single-celled life form. Sadly, I don't remember what it's called and I can't find it online, as the search results are drowned out by the more well-known jellyfish.
The biggest crossover event in history.