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Human gene linked to bigger brains was born from seemingly useless DNA
- seydor 4y agoI for one welcome our big brain mouse overlords. We frankly know more about them than we know about ourselves.
- deleted 4y ago[deleted]
- xeromal 4y agoThis brings up a question for me. Does brain size always correlate to intelligence? I see a dolphin brain that looks very human and I think that it does, but then I see how smart crows are and I'd honestly say that they're smarter than my dog in most ways.
- bpodgursky 4y agoWithin generally similar animals, brain size is correlated with intelligence. Across different branches of the tree, it's harder to compare. Bigger bird brains ~= smarter birds. Bigger dog brains ~= smarter dogs. But you can't directly compare dogs and birds in that way.
- kanzure 4y agoIt's the absolute number of cortical neurons, not the size of the brain. "Brains matter, bodies maybe not: the case for examining neuron numbers irrespective of body size" https://nyaspubs.onlinelibrary.wiley.com/doi/10.1111/j.1749-6632.2011.05976.x https://nyaspubs.onlinelibrary.wiley.com/doi/10.1111/j.1749-... "No relative expansion of the number of prefrontal neurons in primate and human evolution" https://www.pnas.org/doi/full/10.1073/pnas.1610178113 https://www.pnas.org/doi/full/10.1073/pnas.1610178113 "The human brain in numbers: A linearly scaled-up primate brain" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2776484/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2776484/ "The elephant brain in numbers" https://www.frontiersin.org/articles/10.3389/fnana.2014.00046/full https://www.frontiersin.org/articles/10.3389/fnana.2014.0004...
- bpodgursky 4y agoYeah, I don't think that's in contrast to what I said. Neural architectures are very similar between closely related species, and differ wildly between birds and whales.
- f6v 4y agoI’d rather ask about body/brain ratio and % energy consumed by a brain.
- hutzlibu 4y ago"Does brain size always correlate to intelligence?" Not really, otherwise whales and elephants would be way smarter, than us. Well, some people say, they are, but it does not show in our intelligence tests. And birds brains evolved differently than those of mammals, so maybe they are more efficient with their relative small brain? Because yeah, they are definitely smarter than dogs, who have a bigger brain.
- Zamicol 4y agoMaybe whales are "smarter" than us. How can we empirically test whale intelligence? Their technological abilities are obviously inferior, but I wouldn't be surprised if they were surprisingly intelligent in other ways. I'm trumpet dumb, that doesn't mean I'm not "overall smarter" or "niche smarter" than some people who play trumpet.
- prox 4y ago“For instance, on the planet Earth, man had always assumed that he was more intelligent than dolphins because he had achieved so much—the wheel, New York, wars and so on—whilst all the dolphins had ever done was muck about in the water having a good time. But conversely, the dolphins had always believed that they were far more intelligent than man—for precisely the same reasons.” - Douglas Adams
- xen2xen1 4y agoThis quote is always in the back of my head anytime brain size or intelligence is discussed, and is especially when dolphins are mentioned. And, he has a point.
- prox 4y agoAs I reflect on the quote more and more, I believe the dolphins have the right idea.
- hutzlibu 4y agoBut apparently the dolphins in hitchhikers guide to the galaxy did a bit more, than just having a good time in the water - because unlike the humans, they managed to find a way to leave the earth, when it was destroyed. (Book 4) And this is not further explained in the book, but it likely sounds like technology. And when you want to have and use technology, you have to do more than just splashing around..
- cjbgkagh 4y agoBirds have a higher neuron density. Each neuron is a mini Turing machine running on DNA instructions so they could also have better instinctual software.
- dcow 4y agoNot sure if that analogy holds exactly. Neurons don't “compute”, they simply emit a signal that depends on how “saturated” they currently are, right?
- deleted 4y ago[deleted]
- cjbgkagh 4y agoFeel free to research it. The ‘saturated’ analogy is overly simplistic and elides the incredible complexity of what’s actually going on.
- dcow 4y agoBut neurons certainly aren’t mini Turing machines, either? Happy to inform myself more if you can point me in the right direction.
- svnt 4y agoCells perform a staggering number of parallel computations. Neurons are cells, and perform these same calculations and more in addition to emitting spikes. Spikes, rather than being the major form of computation, appear instead to be a means of maintaining synchronization.
- dcow 4y agoI quite honestly did not think of it this way. But it makes some sense. I always thought cells perform, for lack of a better term, self-maintenance operations independently from their macro function (the receiving and emitting of spikes, in this case). I did not think of the internal operations of a cell being connected to the macro function in any sophisticated or meaningful way. I would love to inform myself better on this topic since it is not by area of expertise, and I have an admittedly cursory understanding.
- gonehome 4y agoIt’s an interesting question and the answer is also pretty interesting: https://obscuredinosaurfacts.com/post/2022/11/30/bird-brains.html https://obscuredinosaurfacts.com/post/2022/11/30/bird-brains... There are a few factors and that post gives a nice overview.
- xeromal 4y agoThanks! I've always been curious. Just opened this up.
- kick_in_the_dor 4y agoI haven't yet read the main article at that link, but its opening links to another long blogpost on whatbuywhy.com about the human brain and it's fascinating! Highly recommended: https://waitbutwhy.com/2017/04/neuralink.html https://waitbutwhy.com/2017/04/neuralink.html
- User23 4y agoDogs have been bred for docility not intelligence. Their wild cousins, wolves, are considerably more intelligent, they’re just prone to get bored and engage in undesirable behaviors. I’m told that it’s very easy to teach a tame wolf tricks, but they quickly lose interest in obviously pointless activities, especially as they mature.
- taneq 4y agoSo wolves have ADHD, right. :P
- svnt 4y agoIf you think about it, ADHD behaviors would likely be much more adaptive in the wild than non-ADHD. It is possible ADHD stems from genetic regression.
- tigerlily 4y agoWhat are you trying to say?
- svnt 4y agoIt is possible that the selective processes that led to ”modern” brains are essentially a process of self-domestication, and certain “diagnoses” are just reflections of diversity in that process. If society collapsed I think it would be more beneficial to be ADHD than not.
- emmelaich 4y agoI've seen studies relating hyperactivity to Neanderthal and older genes. They persist because not enough time has passed to mutate them out.
- taneq 4y agoNot them but just guessing... that most ADHD traits are only 'disordered' if you expect humans to be able to sit still, shut up, and focus exclusively on what you tell them to focus on for 8 hours a day?
- bmitc 4y agoDolphins and orcas specifically actually have higher density of folds in their brains than human brains in addition to being big. The book Deep Thinkers: Inside the Minds of Whales, Dolphins, and Porpoises is quite good.
- sieste 4y agoNot exactly an answer to your question, but a few studies report a weak positive correlation (around .3) between head size and IQ in humans. https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=correlation+head+size+iq&btnG= https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=corr...
- svnt 4y agoBut several in your search, including the twin study, report no correlation, and others report correlation only within race and sex groups.
- clnq 4y agoIf there's a weak correlation in a population, finding no correlation in some subpopulations and a stronger correlation in others is expected. For example, a very weak correlation between GPA and job performance exists. In some disciplines, like law, the correlation is strong. In other fields, like extreme medicine, there is no correlation.
- astrange 4y agoAre there studies on GPAs of extreme medics? …Why? (And how much education did they have? The field includes people who have and haven't gone to medical school, I assume.)
- clnq 4y agoNo, this was meant to be an intuitive example of weak correlation. It could have been about a correlation between the redness of a fruit and its sweetness. For the entire population of fruit, it is weakly correlated. For some apples, it is strongly correlated. And for tomatoes, there is no correlation. Extreme medicine, which includes field, mountain, and battlefield medicine, is a specialization of general medicine. You can study it as a part of various programs. I studied it as a specialization in a general practitioner's MSc program in Central Europe. Depending on the region, it is probably possible to specialize in extreme medicine as a nurse or an EMT. There was a wide range of GPAs in that program because success was measured by a narrow range of criteria that did not include things usually considered "academic aptitude" - mainly the ability to follow resuscitation algorithms in simulations precisely. Some of the things we were scored by automatically were time to ECG, time to defibrillation, correct callouts to the team, intubation depth and time, and chest compression depth and rate. And failing to execute a particular algorithm meant immediate failure. Every other imperfection immediately meant a reduced score, and scoring was entirely metric-based in simulators, not open to human interpretation. Scoring just 45% of the possible grade on tests was considered excellent. You had to demonstrate very high competency to pass. Mediocre knowledge of algorithms or skills in resuscitation was unacceptable because that would severely worsen the outcomes of actual patients. If you either cared about your GPA or were primarily motivated by your GPA at school or university, it was clear that this would be a very difficult specialization for you. It was more for people who excelled in algorithm following, composure under stress, and perseverance; and those who wanted a high skill ceiling.
- taneq 4y agoBirds are smarter per unit of brain matter than mammals and it baffles me why more people aren't intrigued by this.
- catskul2 4y agoWhich people are not intrigued by this?
- perth 4y agoI’ve read there’s decent correlation on a few scientific journals on Google scholar. Namely, that while head size doesn’t guarantee intelligence, if you are predisposed to intelligence you can’t be as smart as someone else who is predisposed to intelligence but has a larger head. See: the spatial packing problem in human brains
- joe__f 4y agoDon't you want to look for something like brain/body mass ratio and see how that correlates with intelligence?
- coyotespike 4y agoYes to a first approximation this is a good heuristic! https://en.wikipedia.org/wiki/Brain%E2%80%93body_mass_ratio https://en.wikipedia.org/wiki/Brain%E2%80%93body_mass_ratio https://en.wikipedia.org/wiki/Encephalization_quotient https://en.wikipedia.org/wiki/Encephalization_quotient
- svnt 4y agoNo because the structure and function of the organ is at least as important as the size. Size (or rather some bound of neuron/glial count + complexity) is more in the necessary-but-not-sufficient category. Secondly the question is not well-posed enough to answer accurately. What is intelligence, in this case? The cytoarchitecture of brain parcels/regions varies significantly. If you have a giant cerebellum you are not going to seem very smart to us, but you may have a very large brain. At the other end, people have lived normal (if perhaps internally simpler) lives with tiny fractions of a typical neocortex. [0] 0 : https://www.sciencealert.com/a-man-who-lives-without-90-of-his-brain-is-challenging-our-understanding-of-consciousness https://www.sciencealert.com/a-man-who-lives-without-90-of-h...
- LarryMullins 4y agoLarger animals tend to have larger brains than smaller animals. If you divide the actual brain size of an animal by the size of brain an average animal that size would have, you get the "encephalization quotient". If you rank some common animals by encephalization quotient, most of the resulting order probably isn't surprising to many people: Human: 7.4 - 7.8 Dolphins: 5.3 Chimps: 2.2 - 2.5 Ravens: 2.49 Dog: 1.2 Cat: 1.0 Some of them are surprising: Mouse: 0.5 Rat: 0.4 Rats are certainly smarter than mice, so this analysis is obviously limited. Still, it seems to generally give expected results. https://en.wikipedia.org/wiki/Encephalization_quotient https://en.wikipedia.org/wiki/Encephalization_quotient
- svnt 4y agoVery familiar with EQ. If you read the wiki article you cited, most of it is references to people disputing the relevance of EQ. eg 0 Currently the best predictor for intelligence across all animals is [forebrain]neuron count.[[5]](https://en.m.wikipedia.org/wiki/Encephalization_quotient#cite_note-houzel2017-5 https://en.m.wikipedia.org/wiki/Encephalization_quotient#cit...) 1 In a meta-analysis, Deaner et al. (2007) tested ABS, cortex size, cortex-to-brain ratio, EQ, and corrected relative brain size (cRBS) against global cognitive capacities. They have found that, after normalization, only ABS and neocortex size showed significant correlation to cognitive abilities. 2 The notion that encephalization quotient corresponds to intelligence has been disputed by Roth and Dicke (2012). They consider the absolute [number of cortical neurons] and [neural connections]as better correlates of cognitive ability.[[16]](https://en.m.wikipedia.org/wiki/Encephalization_quotient#cite_note-16 https://en.m.wikipedia.org/wiki/Encephalization_quotient#cit...)
- cscurmudgeon 4y agoOne analogy is computers: bigger is not more powerful, structure matters more.
- polski-g 4y agoWithin a species, yes. There is a 0.41 correlation between brain size and intelligence in humans, for example.
- JamesBarney 4y agoBirds have evolved to have very space efficient neurons, due to their weight constraints.
- suzzer99 4y agoInterestingly, the biggest bird of all, the ostrich, might also be the dumbest. Or at least ostriches are in the conversation with pigeons and turkeys.
- mtlmtlmtlmtl 4y agoProbably this is because the ostrich doesn't need to be as intelligent. No flight, big clumsy beak etc. And they can avoid predation just by being huge and kicking really hard. City birds like crows and pigeons have puzzles they can play with like getting food out of garbage bins and so on. City birds tend to be more intelligent than countryside birds, even within the same species. I always felt like cats are actually smarter than dogs in a lot of ways. Dogs have a lot of their brain power dedicated to manipulating and communicating with humans, as well as trainability. But untrained dogs just seem kinda stupid and helpless to me whereas cats can learn to be almost completely independent with next to no training. Dogs are evolved from pack animals of course which explains a lot of this. I do love dogs though, just to be clear.
- Breadmaker 4y agohttp://www.xenology.info/Xeno/3.3.htm http://www.xenology.info/Xeno/3.3.htm some correlation atleast.
- terminal_d 4y agohttps://pumpkinperson.com/2019/01/04/what-is-the-correlation-between-iq-and-brain-size-and-how-causal-is-it/ https://pumpkinperson.com/2019/01/04/what-is-the-correlation... https://pumpkinperson.com/2019/08/15/increasing-u-s-head-size-1946-to-2012/ https://pumpkinperson.com/2019/08/15/increasing-u-s-head-siz... Last link has a formula to calculate cranial volume. Animal intelligence is vastly underplayed. Ants seem to be a very intelligent creature but they're little more than part of nature to us. We're similarly adapted to our environment, and those animals are adapted to our patterns and mentation by virtue of millennia of close contact / purposeful genetic pushes (eg, dogs)
- TheRealNGenius 4y ago[dead]
- buywarbonds 4y agoNo. A tiger is not 10x smarter than a house cat.
- feet 4y agoThat assumes the correlation would be linear
- stared 4y agoIt is the easiest way to add more brainpower within the same architecture. Think: adding more RAM or another GPU. Different architectures, like in tech, have different specs. More is not always better, as a bigger brain is costly, and the price is only sometimes justified - as with buying more GPUs.
- hinkley 4y agoDinosaurs had their chance and they lost, but I'm slightly terrified of the idea of a crow scaled up to the size of a chimpanzee, and I actually like corvids (though not as much as some). There are raptors roughly that size, so it's not impossible, unlike scaling an ant to the size of a crow, which would only give you a paperweight made out of chitin. They clearly have a different 'instructions per cycle' ratio from mammal brains.
- stoat_meniscus 4y agoRISC? Reduced instruction set corvidae
- Rury 4y agoBrain size has more to do with body size than anything. Most of your brain functions as a motor control and sensory processing center. To willfully move muscle in your body, requires brain power. This is why after a stroke, and a part of your brain dies, you can lose both the ability to move sections of your body, along with feeling anything in those sections. As so, larger animals have bigger bodies, and hence typically have bigger brains in order to handle/control their larger bodies.
- agumonkey 4y agoI'd be extremely interested, because good biological foundation for intelligence doesn't necessary leads to advanced thinking. Size + internal structure + context.
- xyzelement 4y ago[flagged]
- nobleach 4y agoI remember several years ago reading about "junk DNA" or "useless DNA" in sequences. Even then, I was certain that it probably wasn't "junk", we were just yet to understand it. I wish we'd take that attitude a bit more with science journalism. "It doesn't make sense..... YET".
- andai 4y agoWe need a few more copies of this gene before we can recognize all the patterns ;)
- VeninVidiaVicii 4y agoHello, ChatGPT
- User23 4y agoThat was born of the widely held metaphysical position that evolution is purposeless. Given that assumption one would expect to find plenty of “junk” DNA.
- Geezus-42 4y agoI don't think that follows as well as you think. If the primary goal is survival based primarily on efficient use of energy. A lot of evolution is about organisms becoming more efficient by adapting to their environment. So then keeping unnecessary junk around is inefficient and we would expect orgasms that lose to would benefit and out breed the others.
- deleted 4y ago[deleted]
- fnordpiglet 4y agoUnsurprising our brains are cancerous mutations. Observing the world it’s clear we’ve done little net positive with them.
- sassyonsunday 4y ago> The tragedy of a species becoming unfit for life by overevolving one ability is not confined to humankind. Thus it is thought, for instance, that certain deer in paleontological times succumbed as they acquired overly-heavy horns. The mutations must be considered blind, they work, are thrown forth, without any contact of interest with their environment. > In depressive states, the mind may be seen in the image of such an antler, in all its fantastic splendour pinning its bearer to the ground. https://philosophynow.org/issues/45/The_Last_Messiah https://philosophynow.org/issues/45/The_Last_Messiah
- giantg2 4y ago"Human gene linked to bigger brains was born from seemingly useless DNA" Considering how we've managed to use those bigger brains, that DNA still seems useless. It would be interesting to use seemingly unused DNA to express genes. But I also wonder if these truly lack a function, or if we just don't know the function.
- xyzzy4747 4y agoThe human genome is causing the planet to transition from a beautiful paradise to a seemingly useless ever-growing pile of trash and concrete.
- deleted 4y ago[deleted]
- graderjs 4y agoI've always suspected the junk DNA is where the morphogenetic algorithms are kept. Published science just doesn't know how to decode most of morphogenesis for now.
- ly3xqhl8g9 4y agoDNA specifies proteins, anatomy is not there. Something much more interesting must be going on [1]. [1] Morphogenesis as a Model for Computation and Basal Cognition by Michael Levin https://www.youtube.com/watch?v=ZW73LgOM5Bw https://www.youtube.com/watch?v=ZW73LgOM5Bw (Where is Anatomical Information Specified - from 7:30 onwards)
- graderjs 4y agoMore interesting? What could be more interesting that finding the secret to shape in “junk” ? :)
- ly3xqhl8g9 4y agoSorry for being cryptic. Mr. Levin uses this metaphor [1]: just as in the 1950s in order to change the state of a computer you would have to physically change the wires, in a proportional manner, today, when we play with genes we try to alter state at a hardware level, and from the past 70+ years of software development we simply know there is a better way to control state. Imagine you'd have to pull a soldering iron each time you wanted to switch between Adobe Photoshop and Microsoft Word, to paraphrase Mr. Levin's remark. Therefore, there might not be any morphological secret in the DNA, junk or not: DNA encodes a recipe for the building tools to be used in the eventuality of development. Imagine I would extract the exact state of the transistors from my computer, a ridiculously long string of 0s and 1s. Which strings of 0s and 1s codify this very textbox, its background color, the position of the cursor, the cursor itself? The questions are simply at the wrong level of abstraction, even if of course the state of the textbox is certainly somewhere in that string, but if I wanted to alter state at this wrong level then I would have to move very carefully a lot of 0s and 1s, in a very particular manner, with almost no room for errors, in order to add a simple "a" character to this very textbox. Isn't it much more simple and much more interesting, in the waterfall of effects through the abstraction layers if not in action, to push the key "A" on the keyboard? The question then becomes what is and how do we press the keyboard to alter the morphospace location of a cell, a tissue, an organism. A possible answer researched by Mr. Levin's group is voltage-gated ion channels controlling bioelectrical gradients [2]. Of course, at the lowest level, we are all stardust, a collection of femtoevents between femtoparticles, but we simply do not have to operate at that level to understand and control biology: biology itself has done the work, for at least the past 4+ billions of years of evolution, to increase the level of abstraction, from bonds between carbon and sulfur [3], to rotary motors to store and transfer energy [4], to organisms capable of running some kind of simulation of the world in which their reflected self becomes an agent in the world which sometimes knows they are an agent. [1] Michael Levin | Cell Intelligence in Physiological and Morphological Spaces https://youtu.be/jLiHLDrOTW8?t=1201 https://youtu.be/jLiHLDrOTW8?t=1201 [2] Exploring the Behavior of Bioelectric Circuits Using Evolution Heuristic Search, https://www.liebertpub.com/doi/epub/10.1089/bioe.2022.0033 https://www.liebertpub.com/doi/epub/10.1089/bioe.2022.0033 [3] At the very beginning of life on Earth: the thiol-rich peptide (TRP) world hypothesis, https://pubmed.ncbi.nlm.nih.gov/29139533 https://pubmed.ncbi.nlm.nih.gov/29139533 [4] ATP synthase — a marvellous rotary engine of the cell, https://www.nature.com/articles/35089509 https://www.nature.com/articles/35089509
- 2-718-281-828 4y agobrain size correspond to muscle mass in mammals.
- kurthr 4y agoI think your point is that size correlates with size, but that whales don't seem to be 10x the IQ of humans?
- 2-718-281-828 4y agono, specifically muscle mass. just google it. but obviously size will also correlate with it.
- thriftwy 4y agoThis one is quite suspicious. Imagine you're the proverbial alien tasked with introducing sentient life on Earth without arising much suspicion. Replacing useless DNA with de novo genes (of high correlation) would likely be your favorite approach. Whereas I'm not even sure that a million of generations is sufficient to evolve new genes from scratch (i.e. not via duplication or fixing) Wheteas
- acqbu 4y agoseemingly - is the key word here is this research done by the same people that expect us to believe that the universe simply exploded into existence?
- clint 4y agoWhat an amazingly stupid post lol
- mensetmanusman 4y ago‘Junk’ or ‘useless’ DNA is such silly nomenclature, because obviously we will learn more in the unlimited future, and we know so little about biology now that proclaiming anything useless is short-sighted to the max.
- type0 4y ago> When added to mice, one made the rodent brains grow bigger and more humanlike and then we get IRL "Pinky and the Brain"
- sobkas 4y agoSurface to volume ratio so brains wouldn't boil in hot(African savannah) climate?