Very well explained. You should do a video about yeasts as well, since their ancestors were multicellular but ended up evolving back to being unicellular.
Evolution is somehow simultaneously minimalist and a massive hoarder hahaha. If something has a cost it gets eliminated if the benefit isnt equal to or greater than that cost, but most neutral traits are kept around until genetic entropy gets em.
Anyone who held an office job for a few years and/or spent some time watching a jellyfish can tell that some of the most successful creatures are very simple and don't have brains.
@@magichands135 no. Not at all. Its more like that pwrson that doesnt do much work but make zero trouble, eventually become invisible and can Skip shifts because noone noticies... And still gets paíd Pinnacle of Office job
May i recommend various Science-Channel like Sci Man Dan and Sci Show, but also shine light on the fact that Science-CZcamsrs are blood-related-in-spirit to Atheist-Channels? Try Prophet of Zod and Sir Sirc in quick sucession to see the 2 Main-Flavors, so you see why they're worth your Time.
@@loturzelrestaurant I traveled the world on my spiritual search and decided that religion isn’t for me and have become agnostic, but I appreciate the recommendations
The phrase "Survival of the fittest" has unfortunately (and ironically) been affected by the evolution of language. "Fittest" in that context meant the puzzle piece kind of fit: fitting/suitable; not the exercise kind of fit: strong/athletic. In modern parlance it should be re-phrased as "Survival of the most fitting."
Did you know that H.G. Wells’ “The Time Machine” was originally written with another chapter (or two?) that describes how the time traveler continues his journey into the very very far future? And in that future, the traveler glimpses some small, kangaroo-like animals the size of rats ... but with very human-looking faces! However, this chapter is almost never included in any printing of the book. I suspect that the idea of the evolution - or “devolution” - of humans into something so “primitive” was (is?) too unsettling for most people to even contemplate.
@@akumaking1 what does that mean? Are you making judgment on the perceived intelligence of people you dislike? Because I can't think of any scientifically coherent interpretation.
Not sure if progress and regress are accurate when talking about adaptations to increase fitness within an environment. Humans losing tails would technically be regression yet made us better in our niché of endurance so progressed down that path.
Even more important is reproduction. They only need to survive long enough to reproduce to be a "successful" when it comes to evolution. The crappiest evolutionary traits can survive as long as the population is able to survive just long enough to replicate.
@Krogan Love isnt it simple logic that survival comes before to increase the odds of reproduction, case in point, in the wild, bears would eat their own cubs if its needed to survive to ensure they get a shot at the next season.
H.P. Lovecraft's At the Mountains of Madness describes a race of aliens that settled on Earth, and over the course of eons they lost the traits that made space travel possible for them, their limbs became "atrophied" and they overall became simpler as they adapted to life on Earth. The idea of life evolving from a more complex form always captivated me and gave all sorts of existentialist butteflies but I didn't expect real life evolution to have such extreme examples of this as well...
May i recommend various Science-Channel like Sci Man Dan and Sci Show, but also shine light on the fact that Science-CZcamsrs are blood-related-in-spirit to Atheist-Channels?
“Regressive evolution” is just part of the game. In humans, our reduced fur, our inability to manufacture vitamin C, and our lack of a tail are just a few examples.
@@minimo3631 okay but also, we're the only apes that can launch a football 70 yards, which is pretty cool. Chimps Gorillas and even Orangutans are many times stronger than us but all they can do without falling is uselessly lob a rock in an arc because of their anatomy, whereas our short arms long legs big butts and different shoulders we're the only animals who can kill something from a distance with a stone or pointy stick also i mean plenty of people still climb cliffs and stuff its just pretty hard
En unos años. Todas esas "ventajas" habrán desaparecido para favorecer a los que prefieren quedarse echados en el sofá consumiendo azúcar y grasa sin control. Cuyos cerebros no son capaces de recordar lo mínimo indispensable porque todo se le pregunta al oráculo....,,💻
@@antidogmattic one could argue the multitudes of individual animals within the lineage are the agents. They are the ones who have to solve the problems, after all.
Evolution doesn't solve problems, it's random. We see creatures in the configurations we see because a certain random mutation is more successful. Evolution of species by natural selection.
People tend to forget that evolution's ' goal ' is to adapt to the environment it lives in, not to become as complex and intelligent as possible. If the environment never changes and the creatures that live in it have adapted themselves to the point where death by environmental factors are rare. Evolution pretty much stops. ( correct me if I'm wrong, this is my impression of it )
If an organism is perfectly adapted for it's niche, evolution doesn't stop, it just selects for exactly what that organism already is. Coelacanth, Lobsters, Sharks, Ginko, Ants, just to name a few animals that haven't changed in a long time.
@@flingage you need to head over to Chimerasuchus' channel because the crocodilliomorph line of archosaurs was just as big a rollercoaster as avemetatarsalia (pterosaurs and dinosaurs).
@@TlalocTemporal The interesting thing is, (and there's a Scishow video about this), all the animals (and one tree) that you mention have actually changed a lot in their genes - only the genes that determine what they *look like* haven't changed. It's things like immune systems, hormones, and other internal things that don't cause visible differences on the outside but need to go on changing to stay 'fit enough to survive' in an environment where, for example, viruses and bacteria do still evolve constantly.
The only thing that matters from an evolutionary perspective is reproduction and getting to that point. This is why you will have animals who die after reproducing, as part of the process, who still succeeded.
"It's pretty common among parasites. After all, when a species can exploit the features of their hosts, many of their own features just become redundant. Like nothing more than evolutionary baggage." This kind of reminds me of the theory that one bacterium went inside another larger bacterium and basically became the mitochondria of that cell and stopped working as it's own organism, becoming a part of the larger bacterium/host.
I feel like the term regressive evolution is misleading since evolution isn't progressing towards something (it's just an organism adapting to fit its environment), any "regression" an organism makes isn't a regression at all
I mean, you could argue that almost always evolution has to do with an increase in the complexity of an organism. In that sense regressive could mean going back to a more basic form.
It's "regressive" in the sense that it's reversing or doubling-back on steps that have already been taken (though also taking a step or two to the side). Doesn't imply anything about an intended destination, just about the path taken so far.
Is it me or is Blake getting closer and closer to achieving Superman levels of fitness? Seems to me that he's been taking "survival of the fittest" to its most literal sense!
Kind of a shame that you didn't talk about the SCANDAL hypothesis, which postulates that the radical simplicity and complicated ultraparasitic lifecycle of Myxozoans are explainable by them being derived from a clonally-transmissible _cancer_ of Myxosporean cells that managed to re-evolve a stable form. I mean, it _is_ radical, but it is also radical (dude).
@@capturedflame "the only living descendants of pre Colombian dogs". Uh, there is a lot of descendants of pre colombian dogs. They are entire breeds like the Chihuahua, the peruvian Hairless dog and the Chiribaya dog, which is basically a latin american shepherd.
The molecular clock is clearly a major tool when studying evolution and the deep past. But polymerases can have wildly different error rates, which you have to assume affects how the clocks are measured within and across clades. Would you guys consider doing an episode on that? I think it'd be pretty neat and informative...
May i recommend various Science-Channel like Sci Man Dan and Sci Show, but also shine light on the fact that Science-CZcamsrs are blood-related-in-spirit to Atheist-Channels? Try Prophet of Zod and Sir Sirc in quick sucession to see the 2 Main-Flavors, so you see why they're worth your Time.
6:52 As a Unix geek, there is a utility called "less", which is a more-developed version of another utility, called "more". XD (The "more" command displays output from a file or another program a screenful at a time, instead of the whole thing just flying at you at once. The "less" command does that, too, but unlike "more", which only scrolls one way, a screenful at a time, you can scroll up and down, by a line or a screenful, you can do useful things like search for text, and a bunch more.)
It's also an old artifact of nerd humor. Unix-like systems are filled with inside jokes, retronyms, and the like. GNU = GNU's Not Unix. grep comes from the single-letter commands used in the ex editor and its descendants: Global Regular Expression Print. The newer version of the Bourne shell is bash, the Bourne Again SHell. A lighter, faster implementation is called dash. BTW, "more" got its name from the prompt at he bottom of each screen of text: "--More--".
As far as we know, all existing tetrapods go back to a single fish or a cluster of very closely related fish, but way in the past it happened more than once and the others were out competed. However there are lots of fish today that can hang out on land that are not closely related.
Its not just evolution its all things, alot of engineers make the unfortunate mistake of overcomplicating things, anyone can make a complicated device but a true genius makes something simple that does the same job.
The pictures of myxozoans instantly reminded me of how Giardia looks (intestinal parasite of humans and animals that we vets see alot of) I guess because both have double nuclei, are tear drop shaped and have flagellae
Weirdly while giardia is a protozoan, it is more complex than some mixizoan. I'm a little disappointed they didn't highlight the more complex mixizoans
I have an issue called I can't eat a meal without watching some sort of documentary style video 😭👍🏻 and you uploaded right on time for my supper! Thank you pbs eons 🥰
Evolution being a process with many different results is so important to understand! It's great to have an animal like this that gets us thinking outside the box
I actually discovered this phenomena independently through experimentation, before I had even learned it formally. I was developing yet another natural selection simulation, this one based on "organisms" being emulated extremely simple von neumann architectures (or CPU's). Their DNA was essentially their program. The idea originated from the idea of thinking of DNA as software rather than a blueprint, in lieu of epigenetics. So I had designed them such that certain program instructions had an impact on their interaction with their environment. I set it off, and I realized that all organisms, over multiple runs, quickly converged towards an extremely simple program of only 4 instructions. The problem was that the environment I had designed around it was extremely simple, it was simply a grid where organisms couldn't move, but they could turn, query their neighbours, eat neighbours and procreate into neighbouring cells. The main issue was that each organism operated under the same clock pulse, and there wasn't that much complexity to compute in regards to how and when to consume and reproduce in your sphere (circle?) of influence. So the main deciding resource was simply clock cycles, so it was hugely beneficial to have a small program which attempted the core tasks of attacking and reproducing in all directions often enough nondiscriminatory of any information that could be gathered.
This is amazing. Thank you. Evolution is way stranger and more incredible than science journalism portrays. Again, thank you for covering this. Injected a dose of wonder into my morning.
Simple, especially sessile animals make me wonder if there are any cases where a particular plant, animal, and fungus become harder to distinguish from each other
@hayven angoromanana it wouldn't even take that much; if nothing else, plants have a cell wall of cellulose, fungi of chitin, and animals lack one altogether. I'm just wondering, looking at sponges, if there's a plant and fungus you could put beside one and it's not immediately clear which is which. Like, when the evolution diverged, there might have been a time where they weren't all that different from each other
Um, no, you can't really say that. Now, *LIFE* had been evolving the whole time. But not everything has. Most of today's critters (us included) didn't exist a few handfuls of millions of years ago. So you can't say _we_ have been evolving that long, or the Cheetah, or the Red Tailed Hawk, etc. We can't even say us eukaryotes, altogether, have been evolving that long. (Edited typo)
This was a really cool video guys! In the community post talking about this topic I said that I thought this was *Symbion pandora* and was obviously wrong lol. I’d love to see you guys do a video on S. pandora though because their life cycle is so unique and interesting!
Very interesting that a complex animal even if it's not super complex can become very simple but not too single bacterial complex evolution is very very weird
I always personally thought of evolution as mutations in species of life that happen to get passed down to the next generation, it doesn't matter what the mutations are, just that the individuals must survive long enough to reproduce, in term passing down whatever mutations they had.
It doesn't entirely "not matter" what the mutations are-if they are beneficial in some way, then they can be selected for over subsequent generations (i.e., natural selection), since individuals with that mutation have a better chance at surviving and reproducing. But yes, that's essentially all evolution is at the end of the day! Changes in the frequencies of alleles (which originate from mutations) from generation to generation. The more random method of passing down mutations that you're talking about is the process of genetic drift, where mutations that may be neither beneficial nor harmful can be passed down randomly just based on chance events that allow some individuals to survive and reproduce and some to die, regardless of their fitness. A classic example would be a natural disaster destroying half of a population, and the remaining half repopulates, now with different allele frequencies in the gene pool since the alleles from individuals in the previous population were completely lost from the gene pool.
Hi Blake & the PBS Eons team! I've been watching Eons for a long time now, and I've got to say I'm impressed by how much you've improved as a Host compared to the past. Nice work and thanks for doing what you do :)
genius of you guys to plug this video in your most recent upload i’m a huge fan but i somehow missed this episode when it came out so it felt like getting two uploads in one day
What if millions of years from now humans are not the space travelling pinnacle of civilization we think we'll be but instead we evolve to be weird rodent like creatures that had to evolve to survive an Earth that we trashed?
@@KillenOlsson yeah, though it's based directly on the abusive class system of capitalism rather than the destruction of the current ecosystem through its exploitation (though, well, that's also by capitalists mainly)
3:36 this aside is absolutely hilarious 😂 When people sometimes talk too much about those listed lifestyles, parasites can sound like pleasant alternatives :p
Far Cry 3 taught me I have no desire to ever come face to face with one of those things in real life without several inches of glass between me and it xD
That was really cool! We all know of jellyfishes and anemones, but it seems really incredible that 20% of their family is composed of microscopic parasites!
What the “March of Progress” looks like that I think a lot of people get wrong is that humans evolved from apes. That’s inaccurate, humans are apes. We didn’t evolve from apes because we still technically are apes. Humans, chimpanzees and bonobos share a common ancestor, possibly Ardipithecus, that lived about 4 million years ago. The common ancestor we share with gorillas and orangutans lived much earlier than that. So technically, chimps, gorillas and orangutans are our cousins.
Pan Narrans Sapiens Europus in my case, and by the name probably yourself. I'd love to drop in to Flores and find baby Komodo to train.. Plus meet some Pan Floresensis. North02 does a good vidset on hominid species. Sadly we didn't evolve from Pan Paniscus.
@4:05 its reminds me of the theory that a single celled organism ate another and the swallowed organism shed most of its functions to become mitochondria.
I feel that an organism's evolution should be looked at historically through the lens of efficiency towards its survival in an always changing environment. It should not be a reference to mere physical complexity. For example, viruses and parasitism might be an END result of the evolution of multicellular organisms, IF their biomes force them to adapt accordingly over time.
FINALLY some Myxozoan love! One crazy fun fact is that experts estimate there could be over 50,000 species of these things! Each with its own unique hosts
That's an excellent question. If it shed its DNA like these critters shed their RNA, I'm not sure you'd be able to discern one's genetic history enough to tell.
That's one of the leading theories on the origin of viruses! It's called the reduction hypothesis and the discovery of giant viruses give some credit towards it
Because of all thumbnails showing their time stamp in the bottom right corner in this era of youtube the title I saw was "How the Smallest Animal Got So Simp" and I was horrified.
I think, the term "regressive evolution" is misleading. Evolution is never regressive, never conservative. It's about constant change. Often change involves reduction if it is beneficial. I think this principle could (and should) also be applied to economics and politics.
Called it. I started studying Cryptosporidium to find a cure recently, but have been a casual parasitologist for almost two decades. Glad to see parasites getting some attention lately on eons. They aren't just sculpted by evolution, they are a major driver of it. I'd ask for a crypto episode, but let's face it, we still need to finish the basic research and you covered it's relatives. Personally though, I think crypto is the most elegant of the apicomplexa, even if half of what we know right now is paradoxical.
I am probably only one of has a dozen biologists in the US who teaches about Myxozoa. I am by no means an expert, but they are covered in my Biology of Protists class. Even though they are NOT protists.
This is so messed up. It's nuts how different "animals" alone can be. How are we ever supposed to identify aliens when we find them if even on Earth, we can barely recognize other animals that share the same molecular building blocks as us!
I loved the intro. The fact that we have animals who evolved to eventually breathe air and walk on land before evolving to return right back to our oceans is the only reason I haven't carried this mentality about evolution.
That's a really interesting idea but it wouldn't really be a parasite, since it benefits the host . Which would make it some kind of power-boosting symbiotic organism. Very cool!
@@priapulida Pretty much the benefits of parasites in ecosystems is "what doesn't kill you makes you stronger". Due to the fact that parasites are a non fatal bodily invader that trains their host's immune system to be better at dealing with pathogens. Which is a great thing to have if a dangerous decease rolls around.
I guess? I know that in the human and many other animal digestive systems, they have microbes that eat organic macromolecules like most famously cellulose, that allow the animal to eat foods that are high in the macromolecules that they otherwise wouldn’t be able to. I could see the way though that that relationship started out as being like a parasitic relationship where the microbes were originally stealing the macromolecules from the animal but as they coevolved, the animal became able to completely resist the parasite, meanwhile the parasite got better at digesting the macromolecules and not hurting its host, such that it got to the point it turned into mutualism.
Very well explained. You should do a video about yeasts as well, since their ancestors were multicellular but ended up evolving back to being unicellular.
I'd love to see this!
News to, this would be fascinating to learn about.
I would like to see that.
Mmmmm I watch if they decide to make a video of it
Yeah. It would be nice
The original founders of the minimalist movement.
Evolution is somehow simultaneously minimalist and a massive hoarder hahaha. If something has a cost it gets eliminated if the benefit isnt equal to or greater than that cost, but most neutral traits are kept around until genetic entropy gets em.
"This one sparks joy."
Real “shakers”
XDXDXXDXDXXDXDDXDXDDXDXXXXDX
Yah, they had not yet evolved egos.
Anyone who held an office job for a few years and/or spent some time watching a jellyfish can tell that some of the most successful creatures are very simple and don't have brains.
The more complex an organism the more energy required to support the hardware.
Jelly's and their cousins are amazing products of evolution
That office job comment...
*Chef's kiss*
Its almost like being famous without being talented.
@@magichands135 social parasites.
I mean.. influenzas, ..ers, influencers.
@@magichands135 no. Not at all. Its more like that pwrson that doesnt do much work but make zero trouble, eventually become invisible and can Skip shifts because noone noticies... And still gets paíd
Pinnacle of Office job
Speaking of parasites, the evolution of Anglerfish male or Ceratiidae male as you would probably say, would be nice to see.
AGREE STRONGLY
oh definitely, that'd be so cool!
Not a parasite, but okay
@@Jaxck77 true, but still cool
Yes a video on sexual dimorphism and the mechanisms that make it possible would be great
PBS CZcams Has become what the history channel, animal planet, and some others used to be. Actually educational
May i recommend various Science-Channel like Sci Man Dan and Sci Show,
but also shine light on the fact
that Science-CZcamsrs are blood-related-in-spirit to Atheist-Channels?
Try Prophet of Zod and Sir Sirc in quick sucession to see the 2 Main-Flavors,
so you see why they're worth your Time.
@@loturzelrestaurant I traveled the world on my spiritual search and decided that religion isn’t for me and have become agnostic, but I appreciate the recommendations
Evolution is evolving to adapt to your environment so it doesn’t necessarily mean getting bigger, faster, stronger, etc.
The phrase "Survival of the fittest" has unfortunately (and ironically) been affected by the evolution of language. "Fittest" in that context meant the puzzle piece kind of fit: fitting/suitable; not the exercise kind of fit: strong/athletic. In modern parlance it should be re-phrased as "Survival of the most fitting."
@@benjaminmiller3620 Or possibly as "survival of the suited." Though that may call to mind birds in formal wear. :p
Sometimes the fittest is the smallest and squishiest!
@@KianaWolf So....Penguins? :-)
@@benjaminmiller3620 Actual irony for once. Almost nobody uses that right.
Did you know that H.G. Wells’ “The Time Machine” was originally written with another chapter (or two?) that describes how the time traveler continues his journey into the very very far future? And in that future, the traveler glimpses some small, kangaroo-like animals the size of rats ... but with very human-looking faces! However, this chapter is almost never included in any printing of the book. I suspect that the idea of the evolution - or “devolution” - of humans into something so “primitive” was (is?) too unsettling for most people to even contemplate.
Unfortunately a lot of humans are already in the process of devolving
Spooky
@@akumaking1 what does that mean? Are you making judgment on the perceived intelligence of people you dislike? Because I can't think of any scientifically coherent interpretation.
H.G. Wells was at the break of writing Man after Man
but if people are really just monkeys in clothes, why care at all?
Evolution is all about survival, whatever is need, rather progress or regress, complex or simple, whatever works
Survival of the species, specifically.
Not sure if progress and regress are accurate when talking about adaptations to increase fitness within an environment. Humans losing tails would technically be regression yet made us better in our niché of endurance so progressed down that path.
Even more important is reproduction. They only need to survive long enough to reproduce to be a "successful" when it comes to evolution. The crappiest evolutionary traits can survive as long as the population is able to survive just long enough to replicate.
@Krogan Love hence why many of our debilitating illnesses pop up after the age of reproductive ability.
@Krogan Love isnt it simple logic that survival comes before to increase the odds of reproduction, case in point, in the wild, bears would eat their own cubs if its needed to survive to ensure they get a shot at the next season.
H.P. Lovecraft's At the Mountains of Madness describes a race of aliens that settled on Earth, and over the course of eons they lost the traits that made space travel possible for them, their limbs became "atrophied" and they overall became simpler as they adapted to life on Earth.
The idea of life evolving from a more complex form always captivated me and gave all sorts of existentialist butteflies but I didn't expect real life evolution to have such extreme examples of this as well...
May i recommend various Science-Channel like Sci Man Dan and Sci Show,
but also shine light on the fact
that Science-CZcamsrs are blood-related-in-spirit to Atheist-Channels?
“Regressive evolution” is just part of the game. In humans, our reduced fur, our inability to manufacture vitamin C, and our lack of a tail are just a few examples.
And of course, our arms and legs are no longer made to primarily climb trees.
@@horsepowermultimedia Truly our biggest evolutionary loss
@@minimo3631 okay but also, we're the only apes that can launch a football 70 yards, which is pretty cool. Chimps Gorillas and even Orangutans are many times stronger than us but all they can do without falling is uselessly lob a rock in an arc because of their anatomy, whereas our short arms long legs big butts and different shoulders we're the only animals who can kill something from a distance with a stone or pointy stick
also i mean plenty of people still climb cliffs and stuff its just pretty hard
En unos años. Todas esas "ventajas" habrán desaparecido para favorecer a los que prefieren quedarse echados en el sofá consumiendo azúcar y grasa sin control. Cuyos cerebros no son capaces de recordar lo mínimo indispensable porque todo se le pregunta al oráculo....,,💻
And more recently, our difficulty processing complex information in order to coexist in society...
Evolution: not a linear trajectory, but rather a multifaceted, iterative problem-solving methodology. 👍🏻
Thanks captain obvious
@@antidogmattic one could argue the multitudes of individual animals within the lineage are the agents. They are the ones who have to solve the problems, after all.
@@FluffyToxin Someone is just sharing their insight and your compelled to diminish it … why be rude like that?
Best part is that it has no foresight so we can end up with very strange creatures.
Evolution doesn't solve problems, it's random. We see creatures in the configurations we see because a certain random mutation is more successful. Evolution of species by natural selection.
People tend to forget that evolution's ' goal ' is to adapt to the environment it lives in, not to become as complex and intelligent as possible. If the environment never changes and the creatures that live in it have adapted themselves to the point where death by environmental factors are rare. Evolution pretty much stops. ( correct me if I'm wrong, this is my impression of it )
If an organism is perfectly adapted for it's niche, evolution doesn't stop, it just selects for exactly what that organism already is.
Coelacanth, Lobsters, Sharks, Ginko, Ants, just to name a few animals that haven't changed in a long time.
@@TlalocTemporal
Also crocodilians
@@flingage you need to head over to Chimerasuchus' channel because the crocodilliomorph line of archosaurs was just as big a rollercoaster as avemetatarsalia (pterosaurs and dinosaurs).
@@TlalocTemporal The interesting thing is, (and there's a Scishow video about this), all the animals (and one tree) that you mention have actually changed a lot in their genes - only the genes that determine what they *look like* haven't changed. It's things like immune systems, hormones, and other internal things that don't cause visible differences on the outside but need to go on changing to stay 'fit enough to survive' in an environment where, for example, viruses and bacteria do still evolve constantly.
The only thing that matters from an evolutionary perspective is reproduction and getting to that point. This is why you will have animals who die after reproducing, as part of the process, who still succeeded.
"It's pretty common among parasites. After all, when a species can exploit the features of their hosts, many of their own features just become redundant. Like nothing more than evolutionary baggage."
This kind of reminds me of the theory that one bacterium went inside another larger bacterium and basically became the mitochondria of that cell and stopped working as it's own organism, becoming a part of the larger bacterium/host.
yup that's pretty well accepted in biology now a days.
I feel like the term regressive evolution is misleading since evolution isn't progressing towards something (it's just an organism adapting to fit its environment), any "regression" an organism makes isn't a regression at all
I mean, you could argue that almost always evolution has to do with an increase in the complexity of an organism. In that sense regressive could mean going back to a more basic form.
It's "regressive" in the sense that it's reversing or doubling-back on steps that have already been taken (though also taking a step or two to the side). Doesn't imply anything about an intended destination, just about the path taken so far.
@@therealpbristowah that makes sense, also I guess our own human perception of evolutionary 'progression' clouds it sometimes
"evolution" itself is a misleading term to begin with XD
also why I hate the term "devolving", I feel like it should stay in digimon where it makes sense. evolution is simply change.
Is it me or is Blake getting closer and closer to achieving Superman levels of fitness? Seems to me that he's been taking "survival of the fittest" to its most literal sense!
I’m not ordering but I’m reading the menu if you catch my drift
Kind of a shame that you didn't talk about the SCANDAL hypothesis, which postulates that the radical simplicity and complicated ultraparasitic lifecycle of Myxozoans are explainable by them being derived from a clonally-transmissible _cancer_ of Myxosporean cells that managed to re-evolve a stable form. I mean, it _is_ radical, but it is also radical (dude).
Interesting theory. Can you share links to a more detailed explanation. I would like to read more about this.
If that does turn out to be true, I feel like that would imply that cancers of other species would also be able to turn into their own species.
You're wrinkling my brain, dude.
@@capturedflame "the only living descendants of pre Colombian dogs".
Uh, there is a lot of descendants of pre colombian dogs. They are entire breeds like the Chihuahua, the peruvian Hairless dog and the Chiribaya dog, which is basically a latin american shepherd.
Now without the jargon
The molecular clock is clearly a major tool when studying evolution and the deep past. But polymerases can have wildly different error rates, which you have to assume affects how the clocks are measured within and across clades. Would you guys consider doing an episode on that? I think it'd be pretty neat and informative...
May i recommend various Science-Channel like Sci Man Dan and Sci Show,
but also shine light on the fact
that Science-CZcamsrs are blood-related-in-spirit to Atheist-Channels?
Try Prophet of Zod and Sir Sirc in quick sucession to see the 2 Main-Flavors,
so you see why they're worth your Time.
@@loturzelrestaurant Hit or miss? It's a miss!
@@fandroid6491 ?
6:52 As a Unix geek, there is a utility called "less", which is a more-developed version of another utility, called "more". XD
(The "more" command displays output from a file or another program a screenful at a time, instead of the whole thing just flying at you at once. The "less" command does that, too, but unlike "more", which only scrolls one way, a screenful at a time, you can scroll up and down, by a line or a screenful, you can do useful things like search for text, and a bunch more.)
Less is, indeed, more. 😄🙂
It's also an old artifact of nerd humor. Unix-like systems are filled with inside jokes, retronyms, and the like. GNU = GNU's Not Unix. grep comes from the single-letter commands used in the ex editor and its descendants: Global Regular Expression Print. The newer version of the Bourne shell is bash, the Bourne Again SHell. A lighter, faster implementation is called dash.
BTW, "more" got its name from the prompt at he bottom of each screen of text: "--More--".
I've listened to all the podcast episodes. I've thoroughly enjoyed them, It's definitely a new favorite.
Question: Did all tetrapods diverge from the exact same fish species, or did fish adapt to land several times and tetrapods from different fish?
As far as we know, all existing tetrapods go back to a single fish or a cluster of very closely related fish, but way in the past it happened more than once and the others were out competed. However there are lots of fish today that can hang out on land that are not closely related.
Its not just evolution its all things, alot of engineers make the unfortunate mistake of overcomplicating things, anyone can make a complicated device but a true genius makes something simple that does the same job.
i like the way you phrased certain parts, it sounds like the script was carefully considered to suggest just the right implications of the information
The pictures of myxozoans instantly reminded me of how Giardia looks (intestinal parasite of humans and animals that we vets see alot of) I guess because both have double nuclei, are tear drop shaped and have flagellae
Weirdly while giardia is a protozoan, it is more complex than some mixizoan. I'm a little disappointed they didn't highlight the more complex mixizoans
@@darcieclements4880 but... this was about the _simplest_ critter, not more complex ones. 🤨 How does your wish make sense in this context?
I am so so glad that y'all have done a video on these creatures. I was literally thinking about them just a few hours ago
I have an issue called I can't eat a meal without watching some sort of documentary style video 😭👍🏻 and you uploaded right on time for my supper! Thank you pbs eons 🥰
Evolution being a process with many different results is so important to understand!
It's great to have an animal like this that gets us thinking outside the box
It's interesting to think that maybe virus descend from a more complex thing too for the same reasons.
There are some hypotheses that say exactly that.
@@seb0rn739 I know they have looked at things like Megaviruses as part of at least some of those hypotheses
Viruses are likely polyphyletic with some being stripped down cells and some being dressed up nucleic acids.
sars-cov is human!
"...evolving doesn't have to me becoming bigger, or more complex." Well it looks like I've got a new dating profile.
I actually discovered this phenomena independently through experimentation, before I had even learned it formally. I was developing yet another natural selection simulation, this one based on "organisms" being emulated extremely simple von neumann architectures (or CPU's). Their DNA was essentially their program. The idea originated from the idea of thinking of DNA as software rather than a blueprint, in lieu of epigenetics. So I had designed them such that certain program instructions had an impact on their interaction with their environment. I set it off, and I realized that all organisms, over multiple runs, quickly converged towards an extremely simple program of only 4 instructions. The problem was that the environment I had designed around it was extremely simple, it was simply a grid where organisms couldn't move, but they could turn, query their neighbours, eat neighbours and procreate into neighbouring cells. The main issue was that each organism operated under the same clock pulse, and there wasn't that much complexity to compute in regards to how and when to consume and reproduce in your sphere (circle?) of influence. So the main deciding resource was simply clock cycles, so it was hugely beneficial to have a small program which attempted the core tasks of attacking and reproducing in all directions often enough nondiscriminatory of any information that could be gathered.
This sounds fascinating, would you have any resources you could please share that shed some light on how one might go about this?
Evolution: * invents fish *
Myxozoans: It’s free real estate
FINALLY a full length video again. Very interesting!
This is amazing. Thank you. Evolution is way stranger and more incredible than science journalism portrays. Again, thank you for covering this. Injected a dose of wonder into my morning.
3:36 this lifestyle tangent made me cackle. It was so unexpected and genuine.
You explained this in an approachable and persuasive manner. Thank you.
Simple, especially sessile animals make me wonder if there are any cases where a particular plant, animal, and fungus become harder to distinguish from each other
@hayven angoromanana it wouldn't even take that much; if nothing else, plants have a cell wall of cellulose, fungi of chitin, and animals lack one altogether. I'm just wondering, looking at sponges, if there's a plant and fungus you could put beside one and it's not immediately clear which is which. Like, when the evolution diverged, there might have been a time where they weren't all that different from each other
Last time I was this early for a PBS Eons video, I was a single celled organism
Evolution may not only go towards getting bigger and bigger, but Blake sure does
That little bird at 5:12 (A bluebird) is absolutely beautiful.
Takes the "We're evolving just backwards" to a whole new meaning
Everything on earth has been evolving the same length of time... they all go back to that first common ancestor of all life.
What if life didn’t start with one organism 👀👽😳🙀⁉️
You could argue that you should count generations, in which case many of the smallest and simplest organisms are generally far more evolved.
Um, no, you can't really say that. Now, *LIFE* had been evolving the whole time. But not everything has. Most of today's critters (us included) didn't exist a few handfuls of millions of years ago. So you can't say _we_ have been evolving that long, or the Cheetah, or the Red Tailed Hawk, etc. We can't even say us eukaryotes, altogether, have been evolving that long.
(Edited typo)
Addressing teleologic misconceptions about evolution - me likey! I would love to see more nature of science content related to paleontology!
0:39 we all know that crabs are the ultimate lifeform
This was a really cool video guys! In the community post talking about this topic I said that I thought this was *Symbion pandora* and was obviously wrong lol. I’d love to see you guys do a video on S. pandora though because their life cycle is so unique and interesting!
@@longboy7 same
Good video. “I’ve been called worse” was the funniest line I’ve heard in weeks.
Just the thought that a sort of animal still alive today was set on its path of evolution when fish weren't around yet. Wild.
Very interesting that a complex animal even if it's not super complex can become very simple but not too single bacterial complex evolution is very very weird
Great episode guys. Thanks to everyone involved.
I always personally thought of evolution as mutations in species of life that happen to get passed down to the next generation, it doesn't matter what the mutations are, just that the individuals must survive long enough to reproduce, in term passing down whatever mutations they had.
It doesn't entirely "not matter" what the mutations are-if they are beneficial in some way, then they can be selected for over subsequent generations (i.e., natural selection), since individuals with that mutation have a better chance at surviving and reproducing. But yes, that's essentially all evolution is at the end of the day! Changes in the frequencies of alleles (which originate from mutations) from generation to generation. The more random method of passing down mutations that you're talking about is the process of genetic drift, where mutations that may be neither beneficial nor harmful can be passed down randomly just based on chance events that allow some individuals to survive and reproduce and some to die, regardless of their fitness. A classic example would be a natural disaster destroying half of a population, and the remaining half repopulates, now with different allele frequencies in the gene pool since the alleles from individuals in the previous population were completely lost from the gene pool.
@@rustyshackleford9888 okay yeah I forgot about the detail of genes that may seem attractive to others of their kind.
"I used to be a big city animal like you. But I realized that the hustle and bustle wasn't worth it. So now I am a small city animal".
I love this channel. All the videos are so interesting and they always make me enthusiastic about learning
The true final state of evolution is a crab
Absolutely delightful episode!!!! I love Myxozoans!!
I wonder what is steve doing these days?
Gould was an excellent writer in pointing this aspect of evolution, his insight truly was one of best among evolutionary biologists.
Hi Blake & the PBS Eons team! I've been watching Eons for a long time now, and I've got to say I'm impressed by how much you've improved as a Host compared to the past. Nice work and thanks for doing what you do :)
genius of you guys to plug this video in your most recent upload i’m a huge fan but i somehow missed this episode when it came out so it felt like getting two uploads in one day
What if millions of years from now humans are not the space travelling pinnacle of civilization we think we'll be but instead we evolve to be weird rodent like creatures that had to evolve to survive an Earth that we trashed?
A reverse Mesozoic?
That's pretty similar to the plot of The Time Machine
@@KillenOlsson yeah, though it's based directly on the abusive class system of capitalism rather than the destruction of the current ecosystem through its exploitation (though, well, that's also by capitalists mainly)
Plenty are not utilizing our potential intelligence and they are breeding just fine...
..l oh my goddesss
@3:38 “I have nothing against parasites, I just don’t agree with their lifestyle”
Tunicates when larva form have a hotochord, but when they ecomeadults they loose theirspinalchord.
hoto?
I'm pretty sure some loriciferans have also lost the ability to use oxygen though. So glad you made a video about these cool organisms!
3:36 this aside is absolutely hilarious 😂
When people sometimes talk too much about those listed lifestyles, parasites can sound like pleasant alternatives :p
"Are we jellyfish?"
"No! We are Devo!"
Anyone who says birds dont look like dinosaurs has never met a Cassowary.
Far Cry 3 taught me I have no desire to ever come face to face with one of those things in real life without several inches of glass between me and it xD
That was really cool! We all know of jellyfishes and anemones, but it seems really incredible that 20% of their family is composed of microscopic parasites!
What the “March of Progress” looks like that I think a lot of people get wrong is that humans evolved from apes. That’s inaccurate, humans are apes. We didn’t evolve from apes because we still technically are apes. Humans, chimpanzees and bonobos share a common ancestor, possibly Ardipithecus, that lived about 4 million years ago. The common ancestor we share with gorillas and orangutans lived much earlier than that. So technically, chimps, gorillas and orangutans are our cousins.
Pan Narrans Sapiens Europus in my case, and by the name probably yourself. I'd love to drop in to Flores and find baby Komodo to train.. Plus meet some Pan Floresensis. North02 does a good vidset on hominid species. Sadly we didn't evolve from Pan Paniscus.
When family gathering?
@@rosiehawtrey are you referring to Homo Narrans and Homo Floresiensis?
I've been waiting for this episode. I just hope it's good
Do viruses have a similar story, being extremely simplified versions of some ancient parasite?
I wish my bio teacher showed us this video as an example of molecular clock, I better understand it, AND I have an example right here.
You said these were the only animals that can't breathe oxygen? But what about the anaerobic Loriciferans?
Cool, thanks for telling me about them!
This is why I love the comments section.
@@darcieclements4880 Science youtubers seem to be the exception to the "CZcams comments are toxic" rule.
@4:05 its reminds me of the theory that a single celled organism ate another and the swallowed organism shed most of its functions to become mitochondria.
I feel that an organism's evolution should be looked at historically through the lens of efficiency towards its survival in an always changing environment. It should not be a reference to mere physical complexity.
For example, viruses and parasitism might be an END result of the evolution of multicellular organisms, IF their biomes force them to adapt accordingly over time.
FINALLY some Myxozoan love! One crazy fun fact is that experts estimate there could be over 50,000 species of these things! Each with its own unique hosts
The mitochondria is the powerhou - wait what? No mitochondria? Blasphemy!
In this case, the mitochondria are outsourced.
Cnidarians also used cnidoblasts (stinging capsules) with namatocyst for anchorage. They also uses them for defence and prey.
My dad was a myxozoan, and he died in a simple-folk helicopter crash.
It would scream in horror over what it has become, but it no longer can.
What do we know about the parasitic viruses? Could viruses have evolved backwards from a larger, more complex organism?
Virus are heavily regressive by their very nature
That's an excellent question. If it shed its DNA like these critters shed their RNA, I'm not sure you'd be able to discern one's genetic history enough to tell.
That's one of the leading theories on the origin of viruses! It's called the reduction hypothesis and the discovery of giant viruses give some credit towards it
The trichoplaxes and myxozoans are in a competition for who can be the greatest minimalist in the Animal kingdom.
Evolution is interesting. We go from monkeys to humans to Boris Johnson.
Because of all thumbnails showing their time stamp in the bottom right corner in this era of youtube the title I saw was "How the Smallest Animal Got So Simp" and I was horrified.
I think, the term "regressive evolution" is misleading. Evolution is never regressive, never conservative. It's about constant change. Often change involves reduction if it is beneficial. I think this principle could (and should) also be applied to economics and politics.
*Robert Venturi:* "Less is a bore."
*Myxozoans:* "Hold my everything..."
As soon as he said it's a parasite, my first thought was "Oh, that makes sense"...
I just love him, my most favorite PBS host.
Called it. I started studying Cryptosporidium to find a cure recently, but have been a casual parasitologist for almost two decades. Glad to see parasites getting some attention lately on eons. They aren't just sculpted by evolution, they are a major driver of it. I'd ask for a crypto episode, but let's face it, we still need to finish the basic research and you covered it's relatives. Personally though, I think crypto is the most elegant of the apicomplexa, even if half of what we know right now is paradoxical.
Into the Microcosmos gives several minutes of nothing but tiny critters of one kind or another! It's from Hank Green, of Scissors fame. 🙂
I always thought barnacles are one of those retro evolutionists. Shrimps and crabs are getting tougher and badder, but they literally got stuck.
I am probably only one of has a dozen biologists in the US who teaches about Myxozoa. I am by no means an expert, but they are covered in my Biology of Protists class.
Even though they are NOT protists.
That's very helpful to understand Evolution. Thanks a Mill!
This is so messed up. It's nuts how different "animals" alone can be. How are we ever supposed to identify aliens when we find them if even on Earth, we can barely recognize other animals that share the same molecular building blocks as us!
I loved the intro. The fact that we have animals who evolved to eventually breathe air and walk on land before evolving to return right back to our oceans is the only reason I haven't carried this mentality about evolution.
Is there parasite which makes the host stronger because it’s in the parasites interest to have a long living host
That's a really interesting idea but it wouldn't really be a parasite, since it benefits the host . Which would make it some kind of power-boosting symbiotic organism. Very cool!
Symbiotes, like lichen and coral
@@priapulida Pretty much the benefits of parasites in ecosystems is "what doesn't kill you makes you stronger". Due to the fact that parasites are a non fatal bodily invader that trains their host's immune system to be better at dealing with pathogens. Which is a great thing to have if a dangerous decease rolls around.
yes, venom
I guess? I know that in the human and many other animal digestive systems, they have microbes that eat organic macromolecules like most famously cellulose, that allow the animal to eat foods that are high in the macromolecules that they otherwise wouldn’t be able to. I could see the way though that that relationship started out as being like a parasitic relationship where the microbes were originally stealing the macromolecules from the animal but as they coevolved, the animal became able to completely resist the parasite, meanwhile the parasite got better at digesting the macromolecules and not hurting its host, such that it got to the point it turned into mutualism.
that's minimalism to the extreme right there
"I've been called worse."
Eon humor kind of sticks to you forever. lol
"It's evolving just backwards"
How sturgeons evolved as one of the last remaining plate-armor fish and might be the closest living example to the extinct Placoderms of the Devonian
This is some powerful stuff
This is yours best video. Super deep. Thanks for doing this.
“regressive evolution is common among parasites” me going back to live with my parents
"We are the pinnacle!"
"Bruh, we can't even make our own vitamin C."