ฝัง
- เผยแพร่เมื่อ 17 มี.ค. 2022
- Beware the Adaptationist Fallacy! Not all traits are the result of natural selection, there are many other possibilities such as spandrels and other neutral traits. And in the big scheme of things, is understanding adaptations really the central problem of biology?
Twitter: / subanima_
Instagram: / subanima_
Website (and mailing list): subanima.org
SOURCES + FURTHER READING:
www.subanima.org/adaptationism/
#adaptationism #naturalselection #evolution
Watched this while eating a peanut butter bread with jam, and decided to subscribe.
relatable. I had just finished mine.
And here I am at the crossroads, to make a PB&J or to Not make a PB&J.
@@___Truth___ I chose oatmeal with fruit.
You guys are all sick.😒
Don't you know you should never eat plants babies.
They fill them with poisons and addictive zombie chemicals, to enslave you to raise their babies, then turn you into compost at an early age.
Plants have been around much longer than us, and are far more cunning and dangerous. 🙄
So it's come to this. I'm out of bread but still have peanut butter and jam... and I've got some newspapers lying around. Wish me luck - I'm so hungry I'm feeling deleterious...
If human close to chimpanzee doesn’t have chin as we only had it, we call ourselves the ‘Chinpanzee’
Haha funny!
Ah I have a bit of prognathism (my lower jaw is a bit more protruding than normal), and I perked up, thinking I might be more evolved than my fellow humans. Guess not... Haha!
I think accepting the assumption that a majority of DNA "has no function" is a fraught position to take. We thought a lot *more* of it was "junk" just a few years ago. There's a certain amount of hubris in the ideas here. as they make the almost manifestly wrong assumption that we now do understand what *all* DNA does, whereas we have a history of just ignoring the parts we don't understand now.
Agreed. This is one of those videos that I believe will not age well as we come to understand more about DNA
There are some bits of our chromosomal makeup that are retroviral.
Ditto. But the point is not that it has no function but that it is variability that doesn't significantly alters fitness, that's what "neutral" means. Like people having slightly bigger or slightly smaller noses, slightly thicker or thinner eyebrows, etc. (mind you that skin color is not neutral, it was driven by dramatic selective pressures: solar protection first, vitamin D urgency later).
It's not like it has no function, but it doesn't encode proteins.
Exactly the same thing happened with the brain in the past
Interesting fact related to the panda segment. The evolution of the human thumb (enabling more complex tool use) is a similar example of pleiotropic changes put into motion by the older changes in the foot to allow long distance, energy efficient bipedalism. I would love to see a video on all the features of human evolution that set us apart from other species along these lines.
For a second I thought he was going to say "The male panda's genitals no longer serve any purpose."
Darwin lived in an era in which natural theology was still popularly used to explain the existence of biological function (that is, god created organisms to live in certain ways), and introducing the idea that function could be created and maintained naturally (by natural selection) was revolutionary. But more than a century later we find the possibility of natural selection obvious and intuitive, so now we are free to investigate all of the traits of organisms that are non-functional, or at least non-optimal. Darwin himself discussed this in terms of sexual selection, of course.
A similar debate happened in the history of geology. Initially geologists believed that Earth was largely shaped by catastrophic events, including the biblical flood. In response, other geologists argued that given enough time even gradual, uniform forces could change the face of the planet, and we don't need to use religious myths to explain things. Now we understand that the Earth does change slowly over long periods, but it also suffers periodic catastrophes, like erupting volcanoes, ice ages, and asteroid impacts.
The problem was many capitalist oriented mind saw it as the zero sum game (winners take all) between enterprises and coined the expression survival of the fittest while it just says natural selection logic is about the non-survival of the non-fit to their current environment.
@@The0ldg0atI think that it's partly an issue with the fluidity of semantic meaning. Something being fit for purpose just means it's features don't cause unnecessary frictions when applied to a specific purpose. When that purpose is survival, then it should just mean those with features that better help them survive, will survive. The catchphrase is not wrong but the question of what fitness looks like depends entirely on the situation. On its own It's an empty phrase that people read with a colloquial understanding and missed the entire point of the statement.
True, very true, most phenomena can be explained thoroughly with a natural degree, but the anima remains paradoxical and unexplainable under a mechanical and naturalist paradigm
@@The0ldg0atHerbert Spencer was the person who first coined the term "survival of the fittest" and was largely and more significantly derived from his Naturalistic view of life. His theories regarding naturalism bled into creating a world understood solely by nature and nature alone exempt from the influence of God. So "survival of the fittest" was his mantra which driven partly by Darwins book "On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life". "or the Preservation of Favoured Races in the Struggle for Life"" should give you a clue why he would be called a White Supremacist today as he embraced the idea that Europeans where the favoured race. Capitalism was not the reason but naturalism
If I could save a reply this would be the one. Geology is fascinating and I appreciated the context I wouldn't have remembered otherwise
Great video! One critique: I think a substantial number of biologist would disagree with referring to DNA that doesn't code for protein as "non-functional". That DNA impacts the cell whether it is the energy used for the frequent replication and transcription that DNA, or the interaction that DNA (and it's RNA) has with other molecules in the cell, or cis-regulatory elements within that DNA etc. The function of that DNA is typically more robust to point mutations, but that doesn't make that DNA non-functional
It is non-functional in terms of protein synthesis.
Yeah, it's horrible obsolete vocabulary. "Junk DNA" does encode and is functional, it's just not the bits where the protein chain are encoded as such but we're not just protein, we are "order".
Thanks for actually explaining pangloss and not just saying "it's not important"
Great video. I was familiar with many of the ideas presented, but it's been a long time since I learned about them and you did a great job of presenting the information in a concise and entertaining way.
Have been looking for a theoretical biology/ philosophy of biology channel since forever. Happy to have found one now!
Wonderfully constructed video essay and thank you for all the new to me ideas you exposed me to!
Your videos are amazing man! Nice animations, funny moments, simple explanations, great pacing! Keep doing it my man! I hope this channel grows as it deserves. This content has great quality
I read an article that said we have chins because if we didn’t, our jaws would split in half when we got punched in the face. It explored how chins appeared at the same time that our hands started to be capable of forming fists.
That’s very interesting. Do you have a link to the article?
Omg I just had the same line of thinking. I deduced: males have strong chins bc females prefer those and selected for them. But why would they like them? What comes to my mind when I think of a man with a strong chin? He is perceived as Dominant and intimidating. So this could be related to males fighting? And how do people fight different from apes? They use boxing! And in Boxing you often hear that you need a strong chin to not be easily knocked out. Super interesting that you found such an article!
It could be that by chance, the jaw genes are interconnected with some genes that at some point were essential for a person to live long enough to reproduce.
Mild correction. Males have heavy chins designed to take a punch and that is what started roughly the same time frame. Look at 2 men fight now; you can see the reason.
The idea that the lower jaw was incomplete has never been shown in the fossil record even of our most primate ancestors.
Did John Wayne write that article?
When fish evolved, they evolved with jaw bones, and the amphibians, reptiles, mammals and birds thet have branched off since there have almost all kept the jaw bone.
Hominim & hominid and ape and human jaw shapes have all been niche evolution, teeth shaped to best suit the available foods eaten, and jaw shapes to best accommodate those teeth.
Getting enough to eat and being able to eat it would have had a greater impact on natural selection than winning fist fights.
Great video, really good job with condensing so much work and theory down to such easy-to-understand explanations.
Love your videos!! I’ve always wondered if the things I learn at school are 100% accurate. Thank you for allowing me to think from different perspectives! If possible, could you do a video on epigenetics and the interaction of our genes and the environment?
Different environments select different characteristics.
The array of genes you possess is partially responsive, and like brain cells and muscle fibers, most of them are off at any time unless you’re discovering a real creative way to die. Epigenes are merely a class of genes dramatically less likely to activate than the rest of your genes.
Man, you're channel is incredible!
Your content is great! Congratulations
And thank you for the discussion, i'll get deeper into this for sure, and i'll spread the word haha!
This channel deserves more subscribers. Some of the best explanations I’ve ever seen.
Awesome video! Held my interest and I have no background in such topics. But from various things I've read or seen about medicine, science, and their attending philosophies as of late, holistic approaches are succeeding and age old schisms becoming bridged as false dichotomies are revealed in thinking. Like neutralism vs adaptationism, nature vs nurture, etc. Thank you for sharing
Thanks so much for the feedback! Glad to hear it wasn’t too complex. I think this century will be very interesting for the development of biological theory indeed :))
- Jake
Love your videos, man! Keep up the fantastic work.
Thanks you so much!
I love what you're doing. Thank you so much.
well researched, insightful and simply explained. thank you so much
Fantastic! I would definitely use this as a supplement to readings and lectures. You even broke down the Panglossian part of it!
Thank you!!
Just be warned that the chin actually does have a purpose: it's a lever that allows us to have less chewing muscles than Neanderthals and still bite harder than them, this in turn allows for globularity of the head which almost certainly has something to do with our evolutionary success vs other Human (but chin-less) species.
Great explanation! Thank you for the effort!
i love your videos, and your attitude, and also you’re pretty funny.
This is excellent content! Awesome job!
Interesting video, really sparks a thought.
I'll be waitning for more :))
Thanks so much! Got two videos planned and will be coming out soonish. Trying to stick to one a month :))
- Jake
Thought provoking. Thanks for making it!
This was a very interesting and entertaining video, thank you.
I find that last segment incredibly fucking fascinanting because that same sort of approach (Environment and subjects as interrelated, mutually influencing parts of a system) is currently extremely relevant in humanities in fields like geography (As in, societies and their environments mutually influencing eachother). Its so bloody interesting seeing these sorts of concepts applied to rather different fields, as, in retrospective, shows a lot of their similarities, as well as their own positions within the own development of sciences as a whole. Epistemology is cool as fuck
Amazing video. The niche construction thought is simply beautiful. It is probably very common thing to occur. We as humans took this to another level by adapting our environment to us (spanning from building cities to occupying space on the ISS).
An interesting example came to my mind. It has been shown, that as we are using our smartphones, the number of connections between out thumb and the brain is increasing. Moreover, in some cases, the thigh is more responsive to touch (vibrations) as we carry our phones in a pocket. This isn't really a matter of evolution though. It simply isn't that fast. It's more like an adaptation of our nervous system to a new part of the enviroment. But we made this environment possible in the first place...
very interesting topic & engaging presentation! i think this video offered a different perspective of just how complex & varied the mechanisms & techniques that play into this thing we define as "life". also instant subcribed! 😊💚
Thank you so much!! Glad you liked the video :)
I instantly subscribed. You are destined to have at least 1 million subs soon. I'm an economist but I'veread Stephen J Gould ( Panda's Thumb?) What you are saying is super intriguing. I wi.l now have to study this. Than you.
Thank you for these videos. They are very enlightening for someone like me who only learned biology in hischool but creeps on thinking about it and doesn't always get it to work out.
Great channel!
Thanks!
I’ve always thought of rephrasing “the survival of the fittest” more accurately as “ survival of the mostly random, including the things that are just enough above unfitness not to get the organism killed”
Exactly
we can even shorten it to SOTMRITTTAJEAUNTGTOK
@@name-nam lol “shorten” I know there’s got to be a much less clunky way to say it, but it was a spur of the moment TH-cam comment. Maybe something more like “survival of the highly random yet not egregiously unfit” or something. I don’t know. A better wordsmith than me should come up with a more pithy phrase
@@JohnMiller-mmuldoor survival of the least unhelpful mutations
Evolution is the survival of the good enough
Marvellous. Mind blown. Thank you. (A newly enlightened adaptionist) 😊
your videos are so under rated in my opinion
While random mutation can influence evolution, it's important to note that natural selection is still by far the most important factor. Mutations that may seem neutral may actually have very slight positive or negative effects on a species. Over a long enough period of time, mutations that have slight negative effects would be weeded out and vice versa for positive traits. You can see this in traits such as not having wisdom teeth, this has only a slight benefit but is still naturally selected on.
If only there were a way to prove that baseless assertion. Two hundred years of the theory and there isn’t one because that would mean having access to information that is simple not available. Of course environment exerts an evolutionary pressure. But it’s not a sufficient explanation for most things in complex organisms because there’s so much that’s simply superfluous to a given environment so it isn’t the environment that’s determinative. A “better” adapted species can go extinct while a nearly useless organism survives, even over millions of years. All of your so-called explanations are “just-so” post hoc reasoning and it’s very unconvincing.
@sgttomas Species only go extinct when their environment changes faster than the species can adapt. For example, if a new species comes to compete for the same resources. There are no "better" species that go extinct randomly, and there are no "useless" species that simply survive. Keep in mind that most beneficial mutations only give a slight advantage to an individual. If luck leading to individual outcomes was stronger than this, then evolution wouldn't exist.
@@gatuarhin this is post hoc reasoning and the video provides an alternative way to approach evolution, which of course occurs. It’s just only a small part of the overall story, which is entirely inexplicable at the moment.
Natural selection is when the organisms carrying a mutation
a) can reproduce sufficiently more that those without, and eventually supplant them (adapting to evolutionary niche) or
B) are the only ones capable of living to reproductive age after a major change in the environment or
c) after a major extinction, there seem to have been explosions of diversity among a category of organism, presumably because the environment temporarily increases the rate of mutation and/or allow for easier survival of mutations in a depopulated and less competitive period.
As per the video, mutations happen all the time, at a fairly predictable rate, and most either don't allow the mutated organism to live to reproductive age, or they don't influence the organism's chances of survival either way.
My Dad had three kidneys and one testicle.
Those mutations didn't prevent him from reproducing, but neither I nor my sisters inherited either mutation.
TLDR: Without mutations, no species could adapt to better suit its environment, there'd be nothing for natural selection to select for.
This is the best content I could stumb upon, cant believe you are not famous yet
This was so well made and funny. Have you adapted your videos to gain the engagement unmotivated college kids who don't want to read the original paper.
Thank you for the kind words, appreciate it!
Great video review, thanks !
Thank you. Finally someone has simplified this debate to a level I understand. On "no environment without an organism", sorry, failing to grasp this concept as Big Bang, whole of lot exploding stars and billions of years passed without any organism present. Maybe I am missing something.
It's also important to note that previously useless traits can become useful again, selected for.
As an example: The Chin (by raw chance) is sexually dimorphic, and is, as a result, small chins are strongly selected against in men, but not in women.
Thus, the Chin started off useless, but became useful at a later time as a way of peacocking.
Describing it as selecting against makes more sense than selecting for. Although it’s all just words in the end. People get the idea that NS is creating traits or choosing from them. All it’s really doing is describing the fact that if something doesn’t replicate genes over the course of long time spans than that thing ceases to exist. So by definition, all things that exist are good enough at existing that they still exist. And if they aren’t good enough the go away (or get selected against by NS if you want to put it that way).
No, those traits are a consequence of other changes which were selected for, just as domesticated foxes changed in appearance.
this video needs like 10,000 views
Thanks againnnnn!!
it has 20k views now
@@thecritiquer9407 It's about time
Amazing video, thanks!
Honestly thanks for explaining the chin thing. I’ve heard that my whole life but no one ever put it so simply. I feel dumb but a little smarter now
I feel dumber now
@@DanielAbreu-tz9bl you are duh
You're the only non-textile manufacturer besides myself I've seen try to pull so many threads together. Big Liebnitz fan here, Voltaire straw-manned him, which made funny satire but bad argument. What does random mean, anyway? Back when, I noted that even if we could assume random mutation of genes, evolution couldn't be random if it SELECTED for fitness. (I had to point out that "fit" meant, not Most Buff, but tetrised into the eat and be eaten chain.) 16:37 In spite of Punctuated Equilibrium, Gould was considered a strict Darwinian, but I don't think even Darwin was a strict Darwinian. Wallace was the OG (Original Gradualist). Competitive publication problem, solved by cooperation, who'da thunk? Loving the advance of epigenetics! Give ol' Lamarck a crumb. In summary: What fun you are! Thanks for looking at all the little reduced pieces and making a coherent and detailed picture of them.
Great video! Also, genetic drift can destroy important genes which are currently neutral, but significant longer term. For example human's (and relatives) loss of ability to synthesize vitamin C, though its loss could also have been beneficial. Another is cats losing the ability to synthesize Taurine, which is only found in meat, which is all cats eat. These changes could severely harm the emergence of some herbivore cat or humans ability to travel the seas eating nothing but dried jerky and hardtack. Even if these examples turn out to be advantageous, it seems clear that genetic drift COULD destroy significant, but neutral genes, which hurt the long-term adaptability of a species.
Genetic drift can destroy important genes that are currently beneficial if they're held by a small enough percentage of the population. It is pure randomness, even if your population has better odds of surviving that doesn't guarantee anything.
Another part of the neutral theory which wasn't touched on in this video is that not only are beneficial mutations rare, they're made even rarer by the fact that genetic drift destroys a significant amount of them. Within the first few generations of a gene's existence it is very vulnerable to simply having the entire population carrying that gene be wiped out completely. It doesn't matter how beneficial the gene is, there's always a chance that every member of the species with that gene is killed by a predator when we're talking about a gene that less than ten individuals may have.
i know that no one is proberly going to see this but i felt like expanding of from the perfect world hypothosis you mentioned, the ideas of perfect or good and bad are just subjective perspective based ideas, if we went from this world to a world that was better or perfect in our perspective we would believe it was perfect but if we had always been on that world we would have found different problems that we proberly wouldnt have even considered or cared about if we hadnt originated there. basically what im saying is no matter how good somthing is there will always be bad and vice versa our idea of one never compleatly disapears but would just get smaller but never reach 0, so to know how good or bad our world realy is we would have to know all others. problems may seem big or small to us but may seem bigger or smaller to others.
say you are poor and have just won the lottery all of the problesm you can currently think of can now be fixed, old cloths buy some new onces, hungry you can get food when ever you want, your homeless well now you can by a mansion. now lets say you were always rich but have alot of problems. the money isnt going to help with that as thoes problems have arived regarless of you having alot of money becuase thoes problems are able to exist with you having alot of money the money has no effect or meaning for thoes problems so you will have to find other solutions to thoes problems. so in short we must know everything to know one thing
As a hard determinist, I'm triggered by the gall to even ask such a question. Everything that happens in existance is part of a larger equation that we can sometimes peer into its workings to predict what is going to happen next. Nothing is random, everything's already happened... and I'm not saying this just to feel better about the 3 pigeon stinkbombs that fell on my jacket and beanie this afternoon.
There cannot be a coincidence in an inherently deterministic world
this video is absolutely amazing!
It even cleared up some questions I had about netrual evolution, which is part of an exam I have this week.
Thank you, and godspeed SubAnima
here's where i've been on all this for a few yrs now (from the most foundational, 'on up'):
*Habitat Adaption, Habitat Survival, and Habitat Dominance, for >
*Feeding, Breeding, and Status, for >
*Passing on: Individual and Group Genes, Social Structures, Cultural Values, and Technologies (eg, beaver dam, bee hive)
It is obvious to anyone who has engaged in deep thought, that such intense pondering requires one to sit down, secure their elbow onto the leg, and rest the chin upon the hand. Clearly, as the only species known to engage in this deep thought activity, we are also the only species that requires this extended thinking platform, otherwise known as the "chin".
You've earned a new viewer!
Every single videos you make are super high quality, interesting and awesome. Keep on the good work!
Just wow, thanks for the algorithm that make me find this channel
Nice video! Btw chins evolved to better protect teeth from punches, we are one of the few animals that instinctively punch, also it's an attractive sexual trait because woman like manly men who can take a punch, think about it like a lion's mane sort of deal.
Also beards are more masculine traits like chins that work together to exentuate the jawline, maybe some intimidation factor and posibly may help punches slide off a bit
This is my understanding as well
The jaw is one of the hardest bones in the body. I don't buy the fisticuffs notion though.
However, until a century or so ago, a damaged jaw from any impact could reduce your chances of survival.
imo, until the advent of boxing gloves and Hollywood, you'd be better off hitting places that weren't the most likely place on the body to break some bones on your hand.
@@oakfat5178 Pre-gloves boxing and bareknuckle boxing still around today disagrees. Hitting the chin with your larger knuckles is the safest spot to hit for a clean punch to the head and hitting the head is the only effective way of incapacitating someone when weapons and grappling is not an option. Wrestling/grappling is way more important than boxing though and what fights reduce to if unarmed and not as rulebound. Wrestling is much more common as a sport for competition and play in the past and present since injury is much less likely. And elbows, feet, knees, and forehead are good for striking as well. Punching safely and effectively is definitely more of a refined, trained technique than it is instinctual fighting.
@@skyworm8006 In the journal The Physician and Sports Medicine, the article "Epidemiology of professional bare-knuckle fighting injuries"
suggests that jw injuries and concussions were fairly unlikely in bare-knuckle fighting, compared with fractured hands and facial bones.
Jaw bones are harder than knuckles, but if you think it's low risk, by all means try it out on a consenting adult's chin.
A throat punch has been known to kill and often temporarily disables the victim.
The temple is the thinnest part of the skull, and easier to break than the jaw.
You might damage the cervical spine nerves with a punch to the back of the neck.
0:22 - Without waiting to watch more, my answer is "Why not? It doesn't harm..." I am curious in which direction will you go...
Cool! Thanks for the video
Thanks for watching!
Adorei conhecer esse canal!
Your examples showcase that more knowledge is needed to ascertain anything about the adaptionism point of view. That's true for any theory. What are the testable predictions of the other factors of evolution. What knowledge do we need to say that was a factor (say for chin growth) with reasonable confidence.
A while ago, I made my own extremely basic life simulator where each organism had a set of instructions it would follow, sort of like DNA. These instructions would randomly mutate upon reproduction. What I found was that the organisms would gradually accumulate hundreds of instructions, with most of them being completely useless except for a select few. I was originally kinda confused by this and came up with wild theories, but after watching this video, everything makes sense. There was no reason, it was just random chance.
Let the genome be capable of selecting for ability to mutate
did you gave them any cost for information at all?
@@zuz-ve4ro I tried, but then they became extremely simple. Maybe more adjustment could've fixed that, but I was lazy and didn't feel like it.
@@samuelthecamel did you make it possible for them to select for variability of mutation regions? the idea for this means that the organism can compartmentalize and only expose parts of the genome to mutation as opposed to all at once... though not sure how to get this to evolve naturally, but mutatability needs to be able to mutate.
@@cabudagavin3896 I did have them have a seperate and mutation rate for each type of instruction that could individually mutate, but I don't think that's what you're describing here. That sounds interesting though.
Very nice video. If you are ambitious, you can cover constructive neutral evolution next.
Thank you! CNE is certainly an interesting theory, I haven't thought much about it to be honest, but yes perhaps a future video
New here I just wanna note that all this talk about chins and then BAM yours is like, RIGHT THERE.
Great video! One minor complaint is that chins are an odd example to use, given that people with weak chins are typically far less attractive than other people. I don’t know how universal that viewpoint is, so I don’t know if attractiveness is a plausible explanation for modern chins, but most of your audience probably do view chins as more attractive than lacking them (even though super strong chins are far more polarizing), and may decide natural selection to be a more favorable interpretation of that particular trait than random chance.
Also, quick question, isn’t it possible for new genes to occasionally arise out of non-coding DNA. Obviously not often given the low probabilities involved, and even more rarely positive, but isn’t it a possibility, or does something prevent noncoding DNA from ever being recognized as coding DNA again, and new genes have to always arise from duplicates of existing ones?
I appreciate your click bait title to your video. Kinda overhyped is understating the facts of all scientific studies. Great video !
A geologist once said, "If we ever find a planet that looks like Earth we can be certain that life has existed there, because it is living organisms that have shaped it"
He was referring to granite and chalk and such
Okay but this is so interesting!
Thanks Sun!
I think I love this channel. Obviously (now that I've watched this video) we're attracted to the world we see, hear and know. And that's the one we believe in. But there's more to a pale blue dot than you'd know from a distant fly-by on the way back to Andromeda Z-89/&~55.
Desperate evo cope artistry is overhyped? Who could've guessed
Natural selection brought me here
Great video😁
Drift is very real but only shuffling in the end. If your people randomly gets a bad hand, it will still lose in the end. Natural selection is more about culling the less fit than selecting super-fit ones, although by eliminating the worst hands, you end up with the ones with the best actually existing hands.
My one criticism so far at 6:45. A deleterious mutation is a mutation that lowers an organism’s fitness. It doesn’t make a useless protein but a harmful one
I think what he meant was a mutation that turned a useful protein into a useless one, which is by definition bad for the organism
I'd think that when a mutation for a new trait occurs though, the large the current population the less likely it would be to spread... but, that said, in a larger population you'd have more random mutations occuring, so the overall chance of one of them spreading would remain fairly high. So, if the gene for chins appeared in humans (or one of our ancestors) it's chance of going from one individual to dominant would largely depend on it being a survival trait, or at the very least that individual having a good set of other genes.
If it's spandrels, then I'd argue that the chin is not the adaptation... the smaller jaw do to smaller teeth would be the adaptation. The chin would just be an artifact of that adaptation.
In addition to deleterious, neutral, and advantageous mutations I'd think a lot of mutations are situational. A mutation that makes you taller is great for a creature that eats leaves off of trees, but maybe not so good for a creature that lives tight caves.
You are awesome 💯
i laughed so much during this video. thank you
This is honestly the nicest comment I've gotten in a while - makes me smile to see people enjoying the videos. Thank you!!
Thanks for the awesome video. The Florida snail kite has grown their beak in one generation, in order to eat the African snail.
Agh my picky eater autistic brain cringed at the thought of a nutella sandwich and especially at the thought of mixing nutella with jam (yuck!), but I adored the video. Your energy is great and your organization and presentation of the subject matter is top notch!
Glad the algorithm showed me this channel
Beautiful
Thanks again!
Great video! I studied the genomes of hybrids formed between nascent species in my PhD (I’ll not name the specific organism). There the central assumption is that the vast majority of fixed genetic differences between species/populations are the result drift. To my knowledge I never met anyone up in arms about drift vs. selection. It is interesting to reflect on the Spandrels debate - I often found it difficult to get to grips with the history of these apparently earth shattering debates after the fact. Especially when your field doesn’t see it as a controversy in the present day. Thanks for the insightful video. 😊
Oh hey! I have that same bracelet! Crazy world we live in 🥰
Wow that's so cool !!!!
merci
This is pretty interesting in the context of genetic evolution - individual genes compete to reproduce most effectively within a genome, but a common end result of that competition is complex multicellular life, due to the emergent patterns of those genes cooperating for increased fitness. A trait that is a spandrel in a macroscopic perspective can easily be the result of a gene or genes that's reliant on other genes with more overtly beneficial traits at that level, or even be the product of a gene that's successful at the genetic level and merely neutral to the organism as a whole.
Im fascinated that Leibniz argument is explained by the Architect at the end of The Matrix: Reloaded. I know that scene seemed dull to a lot of people but im still fascinated that conversation happened in a blockbuster movie.
However they are completely different. Architect had to deal with humans with specific traits, and humans are not adapted to the Utopia at all, we are adapted to the environment where there is conflict, aggression and the need to compete for limited resources. All powerful God could just create different humans to fit this better world. Or just artificially support unstable world if it is not possible to be self sustained for some reason.
When you consider the hundreds of millions of years that can span between species, it’s easy to imagine that any specific trait may be a snapshot during a process that takes eons. Consider an animated drawing. Different key frames define the overall movement, but inbetween frames may or may not be intelligible, but they are necessary to get from one key frame to the other over time. Now imagine it takes millions of years to get form one key frame to the other instead of 24 frames. You’re not going to be able to tell if that weird squishing motion or that motion blur is a defined or useful state, but it’s a process. Mutations are random by definition. Who’s to say a mutation is useful or not ? If it doesn’t hurt the species in any way, it’s just propagated until it disappears naturally over eons. Language go through the same changes over time. Their particularities may or may not be useful to communicate anything, but we gain or lose spelling, grammar or even whole words by usage, code transfer, assimilation, erosion or obsolescence.
Whatever the species’ trait looks like now may or may not be useful, but it’s just a snapshot from an extremely slow motion movie.
I need you to make a video just about the animals with chins picture at 0:21.
Chins are for Chinese phone books!...by the way I love your channel.
The truth is the binary "Neutral/useful" is likely too simplistic all change have some effect to sexual/natural selection. change totally neutral will have to be very rare and likely might become positif/negative at some point in a continuously changing environment.
We learned about spandrels at Calarts 👍
Interesting, Genetic drift makes way more sense to me for certain adaptations now, specifically the patterns on animals, and how some of them work for camouflage.
It’s better to think about natural selection as selecting against non-viable traits rather than selecting for beneficial ones. Natural selection doesn’t “create” traits. All it really does is describe the obvious reality that things that don’t survive go extinct.
Simply regarding the title and thumbnail text, it’s important to understand that at the end of the day what natural selection is really doing is weeding out reproductively non-viable traits.
It doesn’t matter if something is the best or most optimal for a given task. All that matters is that it works well enough to continue to exist.
So if something randomly evolves and it works then it stays. If it doesn’t work then it goes away. In this way things that don’t negatively effect reproductive success can stick around.
The point isn’t to believe that natural selection is choosing a bunch of things that work. It’s just eliminating what doesn’t. What we’re left with is traits that are beneficial and traits that don’t matter. Or traits that are harmful but still work enough to not go extinct.
I don’t think natural selection is over hyped. I think people get confused when we personify it. But those nerds who actually study it don’t make the mistakes that lay people do.
This is great news for me tbh
I was always a little troubled by adaptation alone
It just seemed to me like a creature adapting to its environment by randomly mutating and getting obscenely lucky by evolving the proverbial peanut butter and jelly gene would be just.. WAY too unlikely, and take far too long. Genetic drift, combined with a more complete consideration of the relationship between organisms and their environments, and maybe some natural selection sprinkled in for zest, sits much better with me
Same. Adaptationism is just post hoc reasoning which is a really fallacious way to go about asserting things. Seriously, try the same approach in the rest of your life and we’d call it superstition. Silly biologists. Never trying to be consistent in their thinking they reach any conclusion so long as enough others assent to it they call “facts”.
wum adaptaion alone??? this is adaptation at work randomness-bad gets removed-good and not bad->good ones are expressed not bad ones are not expressed. yk just over millions of years
@@redditreviews9698 except the video would like to draw your attention to the controversy of that idea beginning in the 1980s and today is regarded as an anachronism in the evolution of evolutionary theory. Ironic 😉
@@redditreviews9698 Adaption still requires some mutations to be selected for and others selected against.
@@oakfat5178 uhhhh yes??? ???? Bad ones are bad and bring down fitness so only the ones with good mutations survive. That waht I'm saying
this is why scientists are more excited when the same trait evolves again and again independently, then we are more confident that there are adaptation advantages
there is a dynamic hidden in the gene and physical interaction of chemicals and cell behavior, against an environment, evolution is not as random as it may seem, families of species could be sharing a common evolution program that guides them through a subset of possibilities way faster and directed than we can prove right now. This program is life itself and it's extremely expensive to model accurately. Life is not only species and specimens, it's also a system that generates them, this is what we don't understand clearly, we can only point at some small aspects participating in the system. The high level understanding isn't there yet. Take nutrition for instance, we don't even have a clear picture of all the gut bacteria species and how they interact and help or work against us. We can't heal someone that has the wrong ones, it's still a science in its infancy, but it's critical to health and it's the most important aspect of any animal life. We can't read someone's epi-genetics, we can't read someone's immune system state (all memory gathered, all cells activation state, all produced antibody) we can't fix hormonal issues at the root (only compensate with huge side effects), mental health is still hard to improve. We seem to improve our way of life but disease rate skyrockets All of this is about only one species and we don't have a clue or we need all the science strength to diagnose one individual as a study only partially at huge costs. We're sill far from fully simulating an animal lineage to prove any theory. I suspect that individuals control their descendant evolution in a limited way but in a directed way, only a few generation exposed to big changes will evolve drastically. Then there is a superseding system in which descendant must belong, this system belongs to the species family, this system evolves slower and you do not need to evolve it a lot to produce seemingly completely different species. For instance cats, apes, dogs, horses have many variants but they share most of this framework within their group, what we need to learn is how signals go to living experience to evolution, what are the variable that are controlled when producing offspring. Could we live better lives by improving the evolution quality to our descendants ?
No one knew anything about genes when Mendel was doing his plant studies. This presentation still points out the importance of natural selection when you threw out the newspaper and peanut butter sandwich. After which, the 99% of neutral adaptions can allow variation without risking extinction. I liked that the presentation started with a question of why the chin, leading to an underappreciated aspect of genetics. Very good presentation 🏆. Definitely worth watching.
We need more if your video
This has an interesting implication for machine learning. Natural selection was a basis for hope for genetic algorithms to create incredible effects as our computers become more and more powerful (quantum computing was especially promising for this). But if the evolution itself, far more powerful than any computer we can dream of creating, gets stuck in its way and never changes, because positive changes in the functional element of DNA by random chance are extremely rare, this dampen the enthusiasm for self-improving programs, who will improve themself by the process of replication and evolution.
be interesting to see how this has played out with covid. Have mutations that give resistance to something like molnuperivar become more common compared to random ones
I think we have a chicken and egg thing going on here. I totally agree with you that changes that arise generation to generation are entirely independent of the environment. But, it is definitely the case that *if* one of those changes makes an organism more fit for survival, it is more likely to survive. Natural selection has nothing to do with what genetic changes *appear* in the population - it has to do with the likelihood of each change *suviving*.
When you look at the incredible complexity of life on Earth in general, you immediately recognize the need for something like natural selection. The unvierse just hasn't been here long enough for us to have "just gotten here randomly." There is some kind of engine contributing to the process.
Dude, you are smart. I'm impressed.