[HN Gopher] A cell so minimal that it challenges definitions of ...
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A cell so minimal that it challenges definitions of life
Author : ibobev
Score : 227 points
Date : 2025-11-26 10:06 UTC (12 hours ago)
(HTM) web link (www.quantamagazine.org)
(TXT) w3m dump (www.quantamagazine.org)
| cnnlives1987 wrote:
| We don't even fundamentally understand physics yet. Certainly
| there is much to life that we don't understand.
| jacquesm wrote:
| This is not so much about the understanding of life as it is
| about the _definition_ of life.
| IAmBroom wrote:
| Eh, you're quibbling with words. We're getting closer to the
| quantum (indivisible) definition of life, and that's
| understanding.
| willis936 wrote:
| I don't think that they are. The term life, as it's
| currently defined, is not very useful. The reality is that
| there is a very colorful spectrum of microscopic biology
| and that a single bin of "alive" and "not alive" is like
| trying to paint the mona lisa with a single pixel.
|
| This scishow video gives a good look at the tip of the
| iceberg.
|
| https://youtu.be/FXqmzKwBB_w
| Noaidi wrote:
| As they said in another comment, life is the ability to
| decrease entropy. That definition would tie in quantum
| mechanics.
| tshaddox wrote:
| I don't think a precise definition of life is particularly
| important or of particular interest to most biologists. This
| thing is life in the sense that it's definitely in scope of
| being studied by biologists (same is true for viruses, of
| course). And the reason it is speculated that it may be
| crucial to understanding life is mentioned in the article:
| "This organism might be a fascinating living fossil--an
| evolutionary waypoint that managed to hang on."
| russdill wrote:
| We understand enough physics to model all the possible
| interactions life might have on this planet. Unless this planet
| is having a really bad day.
| HarHarVeryFunny wrote:
| Maybe better to say "We understand enough physics to model
| all the possible interactions PHYSICS might have on this
| planet".
|
| There are many levels of abstraction between quantum/particle
| physics and life, or even just cosmology (things like dark
| matter, etc), that we really know very little about.
| bloomingeek wrote:
| Let SCOTUS have a look, they seem to know what life is without
| the benefit of any bothersome science.
| flobosg wrote:
| See also: "Microbe with bizarrely tiny genome may be evolving
| into a virus" - https://www.science.org/content/article/microbe-
| bizarrely-ti...
| IAmBroom wrote:
| Which, BTW, is about the same researcher and microbial
| host/parasite pair. More info, so I'm not complaining.
| flobosg wrote:
| Yeah, I should have mentioned that. Article about the same
| topic and preprint, but released earlier this year.
| HarHarVeryFunny wrote:
| Maybe devolving would be a better term if that's the case
| XorNot wrote:
| Reminds me of how the discovery of giant viruses - like truly
| huge viral particles - was immediately also followed by
| discovering "virophages" which parasitized them.
|
| Which of course makes sense to some degree: if an adaptive
| strategy is successful enough, then parasitizing something which
| successfully implements it is going to be resource favorable (and
| likely, presumably by being a member of that species and just
| shedding components you don't need if you take them).
| IAmBroom wrote:
| Indeed. Well deduced.
|
| Inevitability of Genetic Parasites Open Access Jaime Iranzo,
| Pere Puigbo, Alexander E. Lobkovsky, Yuri I. Wolf, Eugene V.
| Koonin https://academic.oup.com/gbe/article/8/9/2856/2236450
| flobosg wrote:
| Unsurprisingly maybe, DPANN archaea can also host viruses:
| https://www.nature.com/articles/s41564-025-02149-7 (Paywalled,
| but there's a preprint at
| https://www.biorxiv.org/content/10.1101/2025.02.15.638363v1)
| djoldman wrote:
| From the paper:
| https://www.biorxiv.org/content/10.1101/2025.05.02.651781v1
|
| > ... we report the discovery of Candidatus Sukunaarchaeum
| mirabile, a novel archaeon with an unprecedentedly small genome
| of only 238 kbp --less than half the size of the smallest
| previously known archaeal genome-- from a dinoflagellate-
| associated microbial community.
| russdill wrote:
| For comparison, the smallest bacteria genome, nasuia
| deltocephalinicola, is 139 kbp.
| smollOrg wrote:
| > According to the shocked researchers
|
| What is this, some content creator run Biohacker Lab in some
| basement on Microflix premises?
|
| Ominous voice: the tiny cell withdrew into the cracks of
| existence and saved it's entire code to be in the lines between,
| the Singular Point which was neither a fraction of space, nor a
| unit of time, hidden in the void of Chututululu's (33rd degree
| cousin of Cthulhu) dreams, written in the unspeakable language of
| the subtext of the book of neither life nor death, that nobody
| would decipher until the time was right AND GODZILLA GETS TO WALK
| THE EARTH AGAIN.
| IAmBroom wrote:
| They were shocked. It is shocking.
| moffkalast wrote:
| Well tell them to quit playing with the stun gun.
| zkmon wrote:
| The ultimate form of outsourcing.
| b3lvedere wrote:
| Which makes C. Regius a very tiny CEO? :)
| falcor84 wrote:
| Only if it has a mechanism to send signals into the host and
| cell. For the CEO metaphor to hold, I'll accept that these
| signals can be entirely ignored, but they need to be
| transmitted.
| zkmon wrote:
| There must be some interaction with the host involved.
| Otherwise there is no point in being hosted or stripping
| off own features.
| falcor84 wrote:
| What do you mean? The interaction described in the
| article is just of the small cell stealing nutrients from
| the host's pouch. That seems like enough of a "point" for
| the parasitic cell, while giving it zero incentive to
| advertise its presence with signals.
| pretzellogician wrote:
| Very impressive! To be clear, this is not the smallest known
| bacterial genome; only the smallest known _archaeal_ bacterial
| genome, at 238k base pairs.
|
| In the article they mention _C. ruddii_ , with a smaller 159k
| base pair genome.
|
| But according to wikipedia, it seems _N. deltocephalinicola_ , at
| 112k base pairs, may be the smallest known bacterial genome.
| https://en.wikipedia.org/wiki/Nasuia_deltocephalinicola
| flobosg wrote:
| A nitpick: Although similar in some aspects, archaea are not
| bacteria; they are classified under their own phylogenetic
| domain.
| api wrote:
| Still far, far too complex to occur "randomly," which is
| fascinating. The odds of 112k bases arranging in any meaningful
| way by chance within a membrane are the kind of thing you
| wouldn't get if you ran a trillion trillion trillion universes.
|
| There's many hypotheses, basically all different variations on
| "soup of organic compounds forming complex catalytic cycles
| that eventually result in the soup producing more similar soup,
| at which point it begins to be subject to differential
| selection." It's a reasonable idea but where did this happen,
| and do the conditions still exist? If we went to that place
| would it still be happening?
|
| There's reason to believe the answer would be no because modern
| lifeforms would probably find this goo nutritious. So life may
| have chemically pulled up the ladder from itself once it
| formed.
|
| This of course assumes no to more fanciful options: panspermia
| that pushes the origin back to the beginning of the cosmos and
| gives you more billions of years, creation by a God or some
| other kind of supernatural or extra-dimensional entity, etc.
| smallmancontrov wrote:
| 1. Autocatalytic RNA reaction networks -- "soup producing
| more soup" -- are easily replicated in the lab, subject to
| Darwinean processes, and are at the center of ongoing study.
| "0 to Darwin" is now easy, "Darwin to Life" is the new focus,
| and God of the Gaps must retreat once again.
|
| 2. Spores hitchhiking on impact ejecta sounds exotic until
| you realize that anywhere life is present at all spores will
| be everywhere and extremely sturdy. That desktop wallpaper
| you have of planets crashing together and kicking off an epic
| debris cloud? Everything not molten is full of spores.
|
| 3. Religious explanations are not in the same universe of
| seriousness as 1 and 2. Opening with a religious talking
| point and closing with a false equivalence is mega sus.
| bavell wrote:
| Would love to see some sources for #1. #2 sounds plausible
| but speculative?
| smallmancontrov wrote:
| RNA World is really cooking:
| https://pubmed.ncbi.nlm.nih.gov/39358873/
|
| Ejection:
| https://link.springer.com/chapter/10.1007/3-540-25736-5_3
|
| Reentry: https://journals.plos.org/plosone/article?id=10.
| 1371/journal...
|
| Not to mention the constant trickle of "X survived in
| space" stories that we get every time someone bothers to
| collect and culture a sample. The amount of success at
| every stage with, frankly, very little effort spent
| tuning the conditions, multiplied by "bacteria are
| everywhere" makes hitchhiking less crazy than it sounds.
| Our intuition misleads us because bacteria are so much
| better at handling acceleration (easy if you're small)
| and dessiccation (everywhere is a desert if you're small)
| than anything we are used to thinking about.
| 9dev wrote:
| Panspermia is pretty much irrelevant to the actual
| question though; even assuming life got to Earth the
| hitchhiker way, it would have to have developed on
| another planet, and we're back to square one.
| alonmower wrote:
| If you're interested in this area I highly recommend "The
| Vital Question" by Nick Lane if you haven't read it.
|
| The TLDR of his theory is that life originated in alkaline
| hydrothermal vents on the ocean floor, where natural energy
| gradients could have driven primitive metabolic reactions
| before the development of DNA.
|
| Book goes into a lot of layperson-accessible detail.
| ferfumarma wrote:
| > Still far, far too complex to occur "randomly," which is
| fascinating
|
| Why spend time making this point? Nobody believes that this
| occurred randomly: it occurred via evolution.
|
| The _mutations_ are a random part of evolution, but the
| process overall is not random at all - no more so than your
| immune system (which randomly generates antibodies, then
| selects against those that target innate epitopes), or stable
| diffusion (which starts with random noise, then marches up a
| gradient toward a known target).
|
| It is the selection step that makes similar processes non-
| random, because a random selection step would just be noise.
| threethirtytwo wrote:
| This is technically random. The entire creationist argument
| is that complexity cannot come from randomness but
| evolution is the method in which it does.
|
| Evolution is just a sort of way for low entropy structures
| to form from randomness. It's still random all the way
| down.
|
| The man is just trying to reconcile a belief in god with
| the scientific reality. He needs to bend the evidence to
| fit his identity he cannot bend his identity to fit the
| evidence because that could break his identity. The fact he
| commented here on this topic is sort of unhinged. It seems
| like the article presented evidence that is strikingly
| against his world view and he needed to justify something
| in order to prevent his identity from rearranging itself
| according to external reality.
| cozyman wrote:
| I'd like to see some form of evidence that creatures can
| change kinds, it seems impossible to me, how do you
| account for that?
| rcxdude wrote:
| The entire fossil record and the mountains of shared DNA
| between very different creatures is pretty compelling
| evidence. Not to mention the idea of changing 'kinds' is
| an entirely human-derived categorisation, not something
| that has some natural definition.
| fwip wrote:
| "Change kinds" is something that only people who believe
| in a rather literal view of the Christian bible say, and
| only because that's the popular fundamentalist argument
| against evolution.
|
| Fundamentally, it's impossible to reconstruct something
| from the fossil record that's convincing to these folks,
| because they will always arbitrarily decide "fossil 1 is
| kind X, and fossil 2 is kind Y, you need to find me
| fossil 1.5," no matter how close in time and likeness the
| fossils are.
|
| So what they actually want is "evolve a lizard species
| into cats" which fundamentally misrepresents both A) how
| evolution works (it does not concern itself with human
| categories) and B) the vast timescale over which small
| changes accrue.
|
| "Kinds" are just human categories we've mapped onto the
| results of billions of years of evolution after the fact.
| akomtu wrote:
| "It's all random all the way down" is just another
| religious belief. Besides, has anyone estimated the
| probability of creating organisms so complex using this
| random evolution scheme? Another problem is why would
| randomly-evolved organisms be so geometrically symmetric?
| I'd expect a random process to create an unholy blob of
| matter.
| rcxdude wrote:
| You're lacking imagination and understanding of how these
| systems form. Symmetry is very commonplace in nature, for
| very unsurprising reasons, because what's random is how
| the processes that create those forms change over time,
| not the entirety of those processes themselves. And yes,
| there is a huge amount of study of how life could form in
| the kinds of environments we think existed on earth near
| the start of life. ATM it's not so much 'how could this
| happen at all' and more 'what looks like the most likely
| way that it happened'.
| api wrote:
| People misread my comment as creationism.
|
| The point I was making was that the complexity curve has to
| meet the floor at some point, and thinking about how this
| happens and what that looks like is interesting.
|
| I was familiar with RNA world but wasn't aware of how much
| progress had been made.
| 0134340 wrote:
| >Still far, far too complex to occur "randomly," which is
| fascinating
|
| I don't see the word "random" anywhere in the article. By
| random maybe you mean it's seemingly indeterministic?
| Regardless of the nature of the underlying process, at the
| classical level, the environment acts as a deterministic
| filter, ie, other chemical processes.
| estimator7292 wrote:
| Good news: the primordial oceans were so vast (literally
| planet-scale) and persisted for so long (millions to billions
| of years) that you _can_ run a trillion trillion individual
| random reactions.
|
| You are being severely restricted by your imagination. You
| seem to have presupposed that random abiogenesis is
| impossible and reconstructed the facts to support that claim
| because you can't conceive of the alternative.
|
| Planets are really, _really_ big. Any one chemical reaction
| is on the scale of molecules. If you let those figures
| compound for a long time, the number of total reactions gets
| very, _very_ large. Far larger than you imagine. Many times
| more.
| reedlaw wrote:
| The probability space of a 140-nucleotide chain is 10^84.
| The estimated number of atoms in the universe is 10^80. The
| hypothesized RNA self-replicator is far simpler than the
| 238,000 base pair archaeal genome. But how are they formed?
| Even the most favorable prebiotic lab conditions have only
| produced short nucleotide chains. Direct chemical synthesis
| only recently achieved chains over 1700 nucleotides long
| [1].
|
| 1. https://www.chemistryworld.com/news/first-direct-
| chemical-sy...
| oersted wrote:
| That's interesting. The main difference seems to be that those
| other tiny organisms only encode how to produce some metabolic
| products for the host but cannot reproduce independently, so
| they are quite close to being organelles. Instead, this new one
| pretty much _only_ produces the proteins it needs to reproduce
| and nothing for the host.
|
| The new one with 238 kbp:
|
| > Sukunaarchaeum encodes the barest minimum of proteins for its
| own replication, and that's about all. Most strangely, its
| genome is missing any hints of the genes required to process
| and build molecules, outside of those needed to reproduce.
|
| Referencing the 159 kbp one:
|
| > However, these and other super-small bacteria have metabolic
| genes to produce nutrients, such as amino acids and vitamins,
| for their hosts. Instead, their genome has cast off much of
| their ability to reproduce on their own.
| codedokode wrote:
| > the bacterium Carsonella ruddii, which lives as a symbiont
| within the guts of sap-feeding insects, has an even smaller
| genome than Sukunaarchaeum, at around 159,000 base pairs
|
| 159 000 base pairs is ~320 Kbit, or 40 KBytes. I wonder, if that
| is the minimum size of a cell firmware. Also, if the cell is that
| simple, can we study it exhaustively and completely? Like,
| decipher every base pair in DNA, and determine what it is
| responsible for. And make an interactive website for that.
| ErroneousBosh wrote:
| This is the biological equivalent of sectorlisp.
| agumonkey wrote:
| Makes me wonder, do geneticist count epigenetic methylation as
| information to add to the genetic information set ?
| empiricus wrote:
| I think the genome might be mostly just the "config file". So the
| cell already contains most of the information and mechanisms
| needed for the organism. The genome is config flags and some more
| detailed settings that turn things on and off in the cell, at
| specific times in the life of the organism. From this point of
| view, the discussion about how many pairs/bytes of information
| are in the genome is misleading. Similar analogy: I can write a
| hello world program, which displays hello world on the screen.
| But the screen is 4k, the windows background is also visible, so
| the hardware and OS are 6-8 orders of magnitude more complex than
| the puny program, and the output is then much more complex than
| the puny program.
| stevenjgarner wrote:
| Isn't replication the single most important act of metabolism for
| an organism? I am trying to reconcile their ""lost genes include
| those central to cell metabolism, meaning it can neither process
| nutrients nor grow on its own" with their "The organism's
| "replicative core" -- the genetic components needed to reproduce
| itself -- remains, making up more than half of its genome".
|
| Replication (making DNA, RNA, and proteins, and ultimately
| dividing) is a highly energy-intensive and material-intensive
| process. What appears to be lost by Sukunaarchaeum are the genes
| to build basic building blocks (amino acids, vitamins,
| nucleotides) from scratch. It cannot find a sugar molecule and
| break it down for energy (it can "neither process nutrients nor
| grow on its own"). Yet it can take pre-made energy and building
| blocks and assemble them into a new organism.
|
| What is the exact line between the host's metabolic contribution
| and the archaeon's replicative assembly? How "finished" are the
| raw materials that the host provides, and how does the archaeon's
| extremely reduced genome still manage the subsequent steps of
| self-replication?
| sigmoid10 wrote:
| You could argue the same way for a lot of parasite species,
| many of which are ridiculously more complex. Is a complex
| multicellular organism (an animal even) not alive because it
| needs to get some component needed for its reproduction from
| another species? If you get hung on such _specific_ components,
| where do you draw the line?
| pron wrote:
| As I understand it, it's not so much that they got "hung up"
| on some specific capabilities for theoretical reasons, but
| that it's rare to find cells without these capabilities. In
| other words, it's nature that seemed so "hung up" on these
| things.
| sysguest wrote:
| well people want simple models and explanations -- just
| like physicists want to model cows as "spherical boing
| boing cows"
| tshaddox wrote:
| Are there any animals which don't need components from
| another organism? Isn't heterotrophy one of the notable
| attributes of Animalia? There are the infamous sea slugs
| which eat algae then use the algae's photosynthetic
| chloroplasts to photosynthesize the chemical energy they
| need, but they still need the algae to make those
| chloroplasts.
| stevenjgarner wrote:
| So in this sense then, human beings themselves are obligate
| metabolic parasites on the planetary ecosystem, particularly
| on other life forms (plants, animals, microbes). The term
| "parasite" here is used in the metabolic sense of relying on
| another organism to produce essential compounds one cannot
| produce oneself. The molecules we must obtain fully
| synthesized from our diet are called essential nutrients. And
| for a Sukunaarchaeum, everything is an essential nutrient.
| neom wrote:
| Agent Smith said a virus:
| https://www.youtube.com/watch?v=L5foZIKuEWQ
| matt-attack wrote:
| We can survive without a constant stream of incoming raw
| materials. I wouldn't think that makes us any less alive. Nor
| are we a parasite on the food.
| sigmoid10 wrote:
| You could make a distinction here in that we only need raw
| materials, we don't need another organism to reproduce.
| Mosquitos can also easily consume raw materials in the form
| of nectar to survive, but they need to take blood from
| other animals if they want to reproduce. If you go along
| this chain of thought, you can come up with arbitrary
| definitions.
| AbortedLaunch wrote:
| We need mitochondria.
| stevenjgarner wrote:
| We need 20 different amino acids to build all our proteins.
| We can synthesize 11 of them (non-essential amino acids),
| but we must obtain the other 9 Essential Amino Acids fully
| formed from the food we eat.
| astrobe_ wrote:
| I wonder if this minimal cell could be described instead as
| something between a bacteria and a virus. I am not a biologist,
| but IIRC viruses penetrate cells then hijack the cell's
| standard machinery to replicate itself, until the cell
| explodes; sort of like a DNA/RNA injection exploit.
| freakynit wrote:
| I've been thinking about a wild theory regarding the incredible
| biological complexity we see in mammals today.
|
| What if our bodies (apart from the brain) are actually the result
| of an ancient aggregation of once-separate "organisms" that
| evolved to live symbiotically?
|
| Over millions of years, their DNA might have fused and co-evolved
| into a single, unified genome. What began as cooperation between
| distinct life forms could have gradually become inseparable,
| giving rise to the intricate multicellular systems we now take
| for granted.
| luxcem wrote:
| It's called Symbiogenesis [0] and it's not at all a wild
| theory. But it's limited to cell components, not multiples
| organs fusing to create something as complex as a mammal.
|
| [0] https://en.wikipedia.org/wiki/Symbiogenesis
| Noaidi wrote:
| I believe that we're living in that situation now. I don't
| think life can be divided into smaller organisms. That there is
| just one complex life that we failed to see based on our past
| prejudice.
| esafak wrote:
| https://en.wikipedia.org/wiki/Intragenomic_conflict
| caymanjim wrote:
| This isn't a wild theory or a novel one. It's well-established
| that endogenous retroviruses alter DNA and are inherited. In
| addition to the primary genome being modified this way, all
| mitochondria are symbiotic organisms inside plant and animal
| cells, with their own DNA, and are vital to life. Same thing
| for chloroplasts in plants. And then there are gut bacteria,
| which are vital to life, symbiotic, and directly influence
| evolution and the genome.
| bavell wrote:
| You should look into the origin of mitochondria.
| busyant wrote:
| Why do you say "apart from the brain"?
|
| Also, as others have noted, your idea is not necessarily wild.
| Certainly, at the sub-cellular level, there is tremendous
| evidence that symbiosis played a part in creating "higher
| level" organisms (i.e., eukaryotes).
|
| Many genomes are like a junk-yard with fossilized relics of
| infectious agent nucleic acid (e.g., viruses), etc. Apologies
| for the junk-yard / fossil mixed metaphor.
| Noaidi wrote:
| Life is the process of decreasing entropy. If they stick with
| that definition, they'd be fine. And they'd find out that life is
| even more abundant than they can imagine.
| chermi wrote:
| What? A liquid solidifying is life?
| Noaidi wrote:
| Water does not decrease its own entropy. If you can't
| understand the distinction I'm making then you do not have
| the imagination and creativity to create new understanding.
| dpark wrote:
| A glass of water in a cold environment radiates away heat
| until it freezes, decreasing its local entropy and
| increasing global entropy.
|
| > If you can't understand the distinction I'm making then
| you do not have the imagination and creativity to create
| new understanding.
|
| Perhaps you could explain your distinction instead of
| insulting people. It's possible you have some interesting
| and insightful distinction but as of now you've not
| explained it nor given any examples of this "more abundant"
| life.
| Noaidi wrote:
| I'm not insulting you. I'm pointing out a reality. You're
| reading comprehension is failing you right now.
|
| Water does not freeze itself. That is the distinction.
| But myself, as a living being, can turn water into ice.
| And I can create an organize materials inside of my own
| body.
|
| I pointed out something interesting. The least thing you
| could do is actually look up to see if there's any
| validity or research on what I'm talking about.
|
| By more abundant life, I'm talking about how the
| definition of life we have is limited, but it's ever
| expanding based on the papers of the original post. I'm
| talking about a greater expansion of our understanding of
| life that's discussed in papers that deal with entropy
| and life.
|
| For instance:
|
| https://www.quantamagazine.org/a-new-thermodynamics-
| theory-o...
|
| But this has been a topic of conversation since the early
| 1900s. It's not like I'm saying anything new.
| dpark wrote:
| This is one of those things that sounds profound, but only
| until you think about it. Depending on how you read this, it
| either excludes life entirely or includes all sorts of things
| that are not meaningfully alive.
|
| 1. Living things locally decrease entropy but globally increase
| it.
|
| 2. Many other processes do the same. As chermi noted, a liquid
| solidifying has the same characteristic.
| Noaidi wrote:
| I definitely choose the second of your two outcomes. That it
| includes all sorts of things that you think are not
| meaningfully alive. But these things are actually life.
|
| Yes, living things locally decrease entropy and that's my
| point.
|
| And maybe I should've been more clear for people who cannot
| grasp new understandings, anything that can decrease its own
| entropy is living.
|
| I mean, do you think life has nothing to do with the
| organization matter into a lower entropy state?
| tete wrote:
| Talking about tiny cells and staring at a tube with liquid. Made
| me chuckle.
| subroutine wrote:
| Impressive. However, still a-ways to go before its as degenerate
| as viruses like SARS-CoV-2 (which have an order of magnitude
| fewer base-pairs)
| andrewflnr wrote:
| This is cool but doesn't say much about the definition of life
| IMO. They're obligate parasites. This isn't a new category.
| They're still eating stuff from their host (probably, given the
| caveat later in the article), and still using it to replicate,
| it's just a more limited diet.
| flobosg wrote:
| > They're still eating stuff from their host
|
| They aren't. Apart from DNA replication, transcription, and
| translation, their genome lacks elements encoding for even the
| most simple metabolic pathways.
| andrewflnr wrote:
| Then where are they getting the materials to replicate? Where
| are they getting the energy? Magic? No, they're pulling pre-
| metabolized materials and energy from the host.
| Y_Y wrote:
| 400K should be enough for any body
| kylehotchkiss wrote:
| Maybe this is a case of an inception of overlapping genes?
| catlikesshrimp wrote:
| Virus are simpler and have challenged the definition of life for
| a long time already. This article excludes virus from life
| because they lack ribosomes.
|
| Last time I checked, they are considered "not alive" when outside
| of a host, and "alive" when inside a host.
|
| About size: "Genome size varies greatly between species. The
| smallest--the ssDNA circoviruses, family Circoviridae--code for
| only two proteins and have a genome size of only two
| kilobases;[61] the largest--the pandoraviruses--have genome sizes
| of around two megabases which code for about 2500 proteins"
|
| https://en.wikipedia.org/wiki/Virus
| threethirtytwo wrote:
| The definition of life is also uninteresting. At its core it is
| just a vocabulary and classification issue. We humans invented
| the word life and we humans chose to make the word vague,
| confusing and differently defined among different people. An
| arbitrary vocabulary and definitional choice for a word "life"
| is not in actuality interesting to think about.
|
| Yet people get hung up about it as if it's a philosophical
| problem. It is not a philosophy problem. The word is loaded and
| you're simply spending an inordinate amount of time trying to
| define some made up boundary of what fits this category you
| made up. It is a communication problem disguised as deeper.
| pfdietz wrote:
| It's like the word "planet", ultimately a tired game of
| definitions.
| tbrownaw wrote:
| Can we also study very small collections of sand to challenge the
| definition of what counts as a heap?
| kylehotchkiss wrote:
| This sounds more like a SuperVirus than a cell to me -\\_(tsu)_/-
| ____tom____ wrote:
| The standard definition of life is too restrictive.
|
| I suggest If it can reproduce and mutate
| heritably, it's alive.
|
| Or, in other words, things that can evolve.
|
| I find the idea that viruses aren't alive ridiculous.
| 3cats-in-a-coat wrote:
| Atoms and sub-atomic particles fit this definition.
|
| Machines fit this definition.
|
| Fire fits this definition.
|
| Truth is "life" is not a distinct category. We just think of
| life as complex life. A complex system that mines energy
| gradients to preserve and replicate its forms.
|
| But there's no hard boundary. It's just in our head.
| halestock wrote:
| How do any of those things fit that definition?
| nrhrjrjrjtntbt wrote:
| Code can fit the definition. Genetic algorithms.
| ____tom____ wrote:
| Yep.
|
| People always come up with people-centric definitions.
| They need to be updated based on what are the fundamental
| characteristic of something that is alive.
|
| The current, more standard definition, seems to be based
| on metabolism. I disagree and argue for reproduction and
| evolution.
| ____tom____ wrote:
| No, none of those can mutate, that's the point of "and mutate
| heritably"
|
| Crystals can "reproduce", but it's always the same (there can
| be errors, but they don't inherit), so they don't count.
|
| And atoms don't reproduce, so I'm missing your point there.
| rbartelme wrote:
| For all the folks saying, "Isn't this just a virus?"
|
| The actual paper states that the genome encodes transfer RNA's
| and ribosomal RNA's. I think that's a really important biological
| distinction missing from the popular press junket. The primary
| source material is well written and elucidates a lot more than
| the Quanta article.
| https://www.biorxiv.org/content/10.1101/2025.05.02.651781v1
| tsoukase wrote:
| Life's two most fundamental properties are homeostasis and
| reproduction. The loss of these two combined with its parasitic
| nature makes this cell a form on non-life.
| anothernewdude wrote:
| Lots of types of life give up on homeostasis along particular
| dimensions because the environment is doing it well enough.
| Viruses do reproduce.
|
| If you say "well not by themselves" neither do humans.
| tsoukase wrote:
| No life exists "by themselves". Self-replication means using
| only its own DNA and not mangling with other's. Virii are not
| only parasites but dead matter (a ribonucl molecule
| surrounded by proteins that happens to stick to other cells,
| like dirt on the skin). Gut microbioma is parasite.
|
| There is another life property that this object does not
| fulfill and is called Teleonomia, that is governed by an
| ultimate goal.
| agumonkey wrote:
| how do biologist consider virus like replication then ? which
| is a two-part system, the virus + the host (and even, a dense
| population of hosts)
| citruscomputing wrote:
| Hm. Not the biggest fan of the "parasite" framing given how
| little we know. I feel the default should be something more like
| lichens.
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