Why is the liver so weirdly regenerative?

(dynomight.substack.com)

40 points | by jbotz 2 hours ago

8 comments

  • vconnor 17 minutes ago
    The punishment for Prometheus stealing fire from the Gods and gifting it to humanity, was to be chained to a rock and having an eagle feed on his liver which would regrow the next day.
  • Aeolun 5 minutes ago
    I feel like this is obvious. Eventually dying of all the weird body failures doesn’t inhibit your ability to procreate, but if you cannot survive alcohol or other various poisons you’ll never make it to a fertile age.
  • amluto 1 hour ago
    The lack of heart cancer might be more complex than the OP imagines:

    https://www.science.org/content/blog-post/no-heart-cancer-th...

    • jaggederest 16 minutes ago
      Other animals do get heart cancer, which is fascinating. It's still very uncommon compared to other cancers, but not virtually absent as it is in people.
  • schnuri 1 hour ago
    I am in awe about how wonderfully engineered by evolution the body is. E.g., what we are able to do with it and how it heals itself when we have an injury. Sure, many people would not live long without external intervention, but many others would. I still want to see the robot that can survive 80 active years without maintenance.
    • dgunay 31 minutes ago
      Well, we do at least have to eat enough food and sleep ~1/3rd of our lives. That's kinda maintenance
      • micromacrofoot 18 minutes ago
        that's absolutely maintenance, without it you have a total system failure in a week
    • ericmay 21 minutes ago
      When you watch those sci-fi shows and folks have nanobots implanted in them that heal wounds really fast or do other cool things I can't help but think in many ways we already have that technology we just need it to do more, faster as our brains and ability to create things have outpaced the rate of evolutionary change.
    • RobotToaster 31 minutes ago
      Humans don't last long without topping up their fluids and consumables.
    • markyc 37 minutes ago
      no you don't
    • chistev 39 minutes ago
      The human body can't survive 80 active years without maintainance. They take drugs, they see the doctor, etc.
      • CookieCrisp 32 minutes ago
        What did people do 500 years ago?
        • EduardoBautista 31 minutes ago
          Die as a child at alarming rates
          • lukan 25 minutes ago
            But those who did not, got quite old without ever seeing a doctor.

            (If we are talking about hunter gatherers, not poor exploited peasants)

            • 1attice 11 minutes ago
              Citation required
  • agumonkey 14 minutes ago
    Anybody on HN knows platforms to discuss this ?
    • gchamonlive 10 minutes ago
      This is a platform and we are discussing this, which means such a platform isn't enough for what you need. Not judging, actually I've felt a degradation in engagement quality as of late, maybe it's personal bias, but the discussions seem more shallow or aggressive.

      In any case, what would you expect from such a platform? That would help with recomendations.

  • card_zero 1 hour ago
    > Evolution decided the good outweighed the bad, and I expect that evolution was right.

    We can expect evolution to do the right thing for the genes. Not for us.

    • cortesoft 35 minutes ago
      I get its just a framework to understand what is happening, but I always hate the phrasing of describing a 'decision' to a process like evolution. There are no decisions being made in the process, just a series of outcomes that lead in a direction
      • someonebaggy 20 minutes ago
        Evolution is literally just the observation that there are lots of things that self-replicate.

        That's it. That's the entire thing. Plus some nuance about things that self-replicate faster than other things...

        It occurs at all levels. Amyloid protein in Alzheimer's patients is self-replicating. So are cells. So are individual parts of cells. Sometimes things replicate by being parts of a larger thing that replicates, sometimes they don't. It's all one big chaotic tangled mess with no particular purpose or design. Human cells evolve, so do humans, so do human societies. So do rocks.

        • cwillu 17 minutes ago
          Rocko can't have kids, because Rocko is just a stupid rock.
      • CookieCrisp 28 minutes ago
        Indeed, I’ve heard so many people misunderstand it because of this type of wording. Like there is still some plan and series of steps we’re following - which really misses the whole point and why it’s worth knowing in the first place
  • bbor 1 hour ago

       I greatly resent having to be a biological organism and subject to all the poor engineering and design decisions that entails.
    
    The first word of that sentence implies its absurdity quite beautifully. She resents, therefor she is.

    And then this:

      Brains. After you reach adulthood, neurons don’t divide. If some of your neurons die—which happens every day—then they’re gone. If you get a brain injury, the other neurons will try to “learn around” the injury, but the neurons themselves are never replaced.
    
    We need more neuroscience in schools! This summary is technically correct ofc, but to imply that the brain is missing some obviously-better option is absurd. We're meat that thinks, y'all; it's far from crap.
    • someonebaggy 19 minutes ago
      IIRC the slow loss of neurons is more than balanced by the additional fine-tuning - unless you get dementia, if course.

      Loss of neurons isn't disastrous as long as it's not too many. Babies are born with several times more neurons than children have, and spend a few months letting all the useless ones die. Apparently it's better to start with a random tangle and prune it to shape (like cutting a box hedge) than to make a hedge grow in a box shape to begin with.

      And IIRC brains can grow more neurons under some circumstances (certain drugs?) - they just normally don't.

      • rzzzt 4 minutes ago
        "While questions remain regarding the precise extent, rate, and functional relevance of adult neurogenesis in the human brain, as well as important methodological considerations, multiple independent approaches now converge in support of its persistence throughout adulthood."

        https://www.sciencedirect.com/science/article/pii/S193459092...

    • done_lurking 8 minutes ago
      Why is it absurd to say that the human brain could be better? That seems obviously true to me.
  • dekhn 1 hour ago
    [flagged]
    • dang 44 minutes ago
      "Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something."

      https://news.ycombinator.com/newsguidelines.html

    • rwmj 1 hour ago
      I can't judge if you are correct or not. It would be more convincing if you could name some of the problems. Since the article is "garbage", there should be lots of things wrong to choose from.
    • haskellandchill 1 hour ago
      I agree. Very shallow "sources" and no qualifications to be speaking on a medical topic. There is a role for pop science to disseminate knowledge but this is pure speculation.
      • dang 15 minutes ago
        There's nothing wrong with speculation on HN. Speculation is intimate with curiosity, and curiosity, not correctness, is the guiding value of this site.

        It may sound odd to demote correctness like that, but it doesn't mean we value incorrectness. Correctness is good, it's just not at the top of the hierarchy. Curiosity—specifically, intellectual curiosity—is what we're optimizing for (https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor...).

        We value the freedom to meander around topics in a curious way. Of course this means following paths that turn out to be wrong [1], but that is how new things are learned, and it's a good way to spend time. In that sense, people are allowed to be wrong on HN. It's part of figuring out what's true.

        [1] not saying the OP is right or wrong - I have no idea about that - but the article looks like the fun kind of meandering speculation that has a good place here.