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-RU-vidrs 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."
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.
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.
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-RU-vidrs are blood-related-in-spirit to Atheist-Channels?
@@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.
“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....,,💻
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.
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-RU-vidrs 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.
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.
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.
"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.
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 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
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
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)
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
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 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!
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
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.
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 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)
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--".
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.
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.
@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.
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'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
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!
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.
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.
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.
3:36 this aside is absolutely hilarious 😂 When people sometimes talk too much about those listed lifestyles, parasites can sound like pleasant alternatives :p
going through the back catalogue of videos and i gotta say. sometimes the funniest thing about these old jokes is just blake's reaction to them (or lack thereof)
