There are animals that don't "age"[1] so of course it's programmed. There's a balance between how often you want to recombine genetics and how long you want to be able to remember. It seems like a better system would have humans decline differently (i.e. no dementia) but having people grow old is almost certainly beneficial to the species.
[1] Their risk of death does not increase after reaching adulthood. I.e. every year after adulthood has the same risk of unexpected death. Humans and other animals that age have their risks of death climb in "old" age.
Naked mole rats are social animals that live in colonies. There are differences of course, but I do not think the evidence suggests that aging is a 'requirement' for complexity. The simplest explanation is that aging is an evolutionary adaption that gives species that age an advantage. Human cells obviously possess the potential to persist past their programmed deaths - that's what cancer is. So I think it's obvious there are no biological limits to us stopping our physical age at whatever stage we want - but I'm equally sure that would involve changes to the experience of being human we may not like (perhaps being in the body of a 20 year old means being in the mind of a 20 year old, for instance).
They seem to have a biological clock and are just more isolated from the effects of aging. Humans are similar that we live three to four times as long as other great apes.
The best example of human cells having programmed death is simply the main exception: offspring.
Children are made from a cell of the mother, combined with some DNA of the father. It is not created out of nothing or from scratch, it quite literally just one of the cells of the mother. So if a child survives one of the cells of the mother survives the mother's death.
Obviously the process involves resetting the "death counter". In fact there's a disease where that step seems to have gotten skipped: progeria.
I've always thought eternal life would steal from the next generation if resources are scarce. If your reaction times, intelligence, etc are always good, and your experience and memories get better, it just seems like you'd out compete your kids and younger cohorts. All well and good but basically stops genetic turnover that got us to this point.
OTOH, you'd accumulate uncurable disease, injuries, etc as well. Maybe you become a disease resevoir inside your own growing family. Or you pass on as-yet-unknown genetic anomalies that are unhelpful, and you do so forever.
Granted that's a modern take, and in particular a modern rpg-like take. Regardless though getting rid of oldies seems like a reasonable way to move a species forward if natural selection is driving "forward".
> getting rid of oldies seems like a reasonable way to move a species forward
This is the real feature of aging, death, and dying. Progress is measured in funerals, not years. If everyone lived forever, nothing would ever change.
There's the saying in science that progress happens 'one funeral at a time,' but that's not because older scientists are less intelligent - it's more like they begin to intellectually ossify. Or in the arts, the critics that rejected Matisse's 'Woman With a Hat' weren't stupid, but their thinking had stagnated.
I think we underrate the value of a fresh perspective. People living longer lifespans would dilute that benefit, imo. Sidenote: this is also an underrated issue with LLMs and their application to science - collapsing to single modes of thought over time.
Maintaining order and fighting entropy is hard, but also planned obsolescence is a good thing for systemic resilience.
You have to regularly clear out the old to both a) keep the process of creating new things well exercised and b) prevent old things from monopolizing resources due to more time to compound interest. Otherwise, you end up with Saturn devouring his son.
most of human evolutionary history was hunter gatherer and survival was subsistence level, and your arguments don't work.
birthing was necessary at least to maintain population, but preferably to expand it. it's only now that we consider "too many" a possibility, and we didn't evolve for this moment.
our history does not show potentially perpetually compounding gains that our children would evolutionarily need a genetic defense against, we already had looting, stealing, and killing.
I think the answer, if there is a programmed obsolesence, is because the genetic admixing of the next generation through sexual reproduction is so useful and important.
> a) keep the process of creating new things well exercised. "We can't build that anymore. We don't know how." A factory that builds things that last too long eventually goes out of business.
In an properly-managed world (not ours), we'd figure out how many factories we need to keep the process knowledge fresh and safe, then have those factories build items that last exactly as long to keep their production steady. Then other factories could make other things. End result: more and better stuff.
Like instead of 1000 washing machine factories that make washing machines that last 5 years each, have 100 that make washing machines that last 50 years.
Instead we get hyper-fast planned obsolescence, pushing the frontier of unreliability and waste creation, so number can go up this quarter.
Waste and inefficiency is the cost of anti-fragility that's necessary to not go extinct when the unexpected happens.
Your world would also slow down innovation. Those old machines were much more energy hungry and only rapid iteration has made them dramatically more efficient.
>when he became acutely aware that his grandparents and parents were not going to live forever…Cao turned to science. Finding a way to slow aging became his lifelong goal
Nothing is supposed to persist forever it doesn’t even make sense to try
This is the real answer. Nature only cares that the old already mixed their genes. So, from an evolutionary biology perspective, it's good to clear out the old stock at the end of every generation. Nature already got whatever it was gonna get out of us at that point. To allow that set of genes to stick around actually yields negative returns, ie - less chance of producing improvements, at that point. (Again, just from the perspective of "Mother Nature" so to speak. Obviously the animals themselves would rather not die.)
Mother nature has no perspective. There are no improvements either, only things that are and are not. Everything is dependent on local context at the present point in time and framing whether it is "good" or "bad" (e.g. one could frame our intelligence as good or bad given how it resulted in anthropocentric climate change that may doom us in time, while 'dumber' species have existed for millions of years without wiping themselves out).
What works today may not work tomorrow. What didn't work yesterday may work today. Evolution is not linear. It tends to happen in bursts almost like a dam busting loose. A constant cycling between periods of genetic diversity (i.e. big resetting just happened, no winners taking all quite yet), and what is known as allele fixation (a winner emerged, oh god no...).
Reminds me of a thought I had about galaxies being instance runs while writing Github actions to build database binaries.
Each galaxy and any planets/life it contains are just artifacts of an "existence run." That's why life feels like a simulation so often (and human history repeats itself): we're inside of an organic (human word) "program" that's trying to perfect itself by running similar, but consistently tweaked "logic" over and over (a macro of sorts). Things like evolution are just an algorithm embedded in the system.
If the theory discussed in the article is correct, then aging is (in the scope of the above thought) just one program among several that we interpret as existence/life.
I think death has some actual benefits. Yes, some of our comfort with death comes with learning to live with its inevitability, but it has genuinely some upsides. I think they have some to do with being able to change things and institutions, but mostly it centers around our brains and psychology. Our life cycle is connected to how our brain develops and matures, inherently I think.
For example, if you go through some events in your childhood, they may stick with you until your death, as an inevitable part of you. Sure, treatment helps, but probably some memories you can't just erase.
Recycling things into a next generation, with probably better living conditions seems like generally pretty positive thing.
Also, some time you'd probably start to stop learning, not necessarily due to brain aging and neuron death, but simply because of basic architecture of our brain and how information solidifies and it starts to become more difficult to learn new things. We are a little more bored of most things and a lot of mystery and wonder diminishes somewhat.
25 years ago I had a spirited discussion with my AP Biology teacher where I posited a similar theory when we were discussing (and running experiments on) genetic mutations. It was "spirited" because she was rather dismissive of the idea, and my (likely overconfident) teenage brain did not understand her response and reasoning. She was otherwise a great teacher.
There's been several articles over these last decades that have covered different iterations of genetic aging, and I think about that discussion every time. I wonder if she's read any of them and also thought about that discussion.
In biology, there are always many causes, of course.
I wonder if people are familiar with the hypothesis of parasite-driven aging.
Parasites are vastly more prevalent than most people in modern, sanitary, medicated societies realize. Studies show that over half the biomass in a region may be parasitic.
Parasite frequently keep the host alive, but inhibit reproduction. This leaves the host alive, and competing with healthy members of its species for resources, but no capable longer reproducing. It's evolutionary dead weight.
Death is basically "turning it off and on again", just as you would do with a computer, and for very similar reasons. It clears the accumulated parasites and starts fresh.
This would also help explain why death is strongly conserved.
One programmed reason for aging is Telomere shortening which kills cells after X reproductions (Hayflick limit) which is part of our body's general anti-cancer defenses.
A big issue with the programmed aging theory is that while we already have pretty good evidence from a biological perspective of a programmed aging clock, it is harder to find an evolutionary justification for it.
I don't know how the antagonistic pleiotropy theory is doing. If true it would be a satisfactory explanation from an evolutionary point of view but I recall that it had some problems.
Otherwise I don't find the other evolutionary explanations of programmed aging to be satisfactory, especially when you consider that genes are selfish and act on the individual rather than population level.
Perhaps reproductive aging (egg quality) is the ultimate limiter, and then overall aging is adaptive downstream of that because hunter-gatherer families benefit (in terms of evolutionary fitness) from fewer old people to increase the percentage of people at reproductive age? That would fit the modern evidence of early egg freezing significantly increasing reproductive success in older women, showing that the problem of fertility decline by age is primarily cellular.
Or perhaps the aging mechanism is leftover from pre-human ancestry and there simply wasn't enough time in our evolutionary history for humans to evolve longer lifespans, maybe because it's slightly helpful but not nearly as helpful as other traits like intelligence, and lifespan is hard to improve via genetic adaptation due to bottleneck effects?
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[ 3.7 ms ] story [ 48.4 ms ] thread[1] Their risk of death does not increase after reaching adulthood. I.e. every year after adulthood has the same risk of unexpected death. Humans and other animals that age have their risks of death climb in "old" age.
Children are made from a cell of the mother, combined with some DNA of the father. It is not created out of nothing or from scratch, it quite literally just one of the cells of the mother. So if a child survives one of the cells of the mother survives the mother's death.
Obviously the process involves resetting the "death counter". In fact there's a disease where that step seems to have gotten skipped: progeria.
OTOH, you'd accumulate uncurable disease, injuries, etc as well. Maybe you become a disease resevoir inside your own growing family. Or you pass on as-yet-unknown genetic anomalies that are unhelpful, and you do so forever.
Granted that's a modern take, and in particular a modern rpg-like take. Regardless though getting rid of oldies seems like a reasonable way to move a species forward if natural selection is driving "forward".
This is the real feature of aging, death, and dying. Progress is measured in funerals, not years. If everyone lived forever, nothing would ever change.
Including our fundamental biology.
If we want a chance at improved, more resilient biology, aging and death have to be a part of that.
For instance, both of us in this conversation will die someday. It is a guaranteed fact.
The question then becomes: how do we live our lives well in view of that fact?
This is almost the stated intention of longevists.
I think we underrate the value of a fresh perspective. People living longer lifespans would dilute that benefit, imo. Sidenote: this is also an underrated issue with LLMs and their application to science - collapsing to single modes of thought over time.
Maintaining order and fighting entropy is hard, but also planned obsolescence is a good thing for systemic resilience.
You have to regularly clear out the old to both a) keep the process of creating new things well exercised and b) prevent old things from monopolizing resources due to more time to compound interest. Otherwise, you end up with Saturn devouring his son.
birthing was necessary at least to maintain population, but preferably to expand it. it's only now that we consider "too many" a possibility, and we didn't evolve for this moment.
our history does not show potentially perpetually compounding gains that our children would evolutionarily need a genetic defense against, we already had looting, stealing, and killing.
I think the answer, if there is a programmed obsolesence, is because the genetic admixing of the next generation through sexual reproduction is so useful and important.
In an properly-managed world (not ours), we'd figure out how many factories we need to keep the process knowledge fresh and safe, then have those factories build items that last exactly as long to keep their production steady. Then other factories could make other things. End result: more and better stuff.
Like instead of 1000 washing machine factories that make washing machines that last 5 years each, have 100 that make washing machines that last 50 years.
Instead we get hyper-fast planned obsolescence, pushing the frontier of unreliability and waste creation, so number can go up this quarter.
Waste and inefficiency is the cost of anti-fragility that's necessary to not go extinct when the unexpected happens.
Your world would also slow down innovation. Those old machines were much more energy hungry and only rapid iteration has made them dramatically more efficient.
Nothing is supposed to persist forever it doesn’t even make sense to try
"Supposed" by whom?
Also, entropy may not be directly related to the biological process of aging. I mean, that's the point of TFA.
Perhaps instead of "forever," we could settle for, let's say, a thousand years in good health?
Besides, if people know they'll be around for longer, they will have more incentive to take care of the place.
What works today may not work tomorrow. What didn't work yesterday may work today. Evolution is not linear. It tends to happen in bursts almost like a dam busting loose. A constant cycling between periods of genetic diversity (i.e. big resetting just happened, no winners taking all quite yet), and what is known as allele fixation (a winner emerged, oh god no...).
Each galaxy and any planets/life it contains are just artifacts of an "existence run." That's why life feels like a simulation so often (and human history repeats itself): we're inside of an organic (human word) "program" that's trying to perfect itself by running similar, but consistently tweaked "logic" over and over (a macro of sorts). Things like evolution are just an algorithm embedded in the system.
If the theory discussed in the article is correct, then aging is (in the scope of the above thought) just one program among several that we interpret as existence/life.
Just a daydream but fun to think about.
For example, if you go through some events in your childhood, they may stick with you until your death, as an inevitable part of you. Sure, treatment helps, but probably some memories you can't just erase.
Recycling things into a next generation, with probably better living conditions seems like generally pretty positive thing.
Also, some time you'd probably start to stop learning, not necessarily due to brain aging and neuron death, but simply because of basic architecture of our brain and how information solidifies and it starts to become more difficult to learn new things. We are a little more bored of most things and a lot of mystery and wonder diminishes somewhat.
There's been several articles over these last decades that have covered different iterations of genetic aging, and I think about that discussion every time. I wonder if she's read any of them and also thought about that discussion.
I wonder if people are familiar with the hypothesis of parasite-driven aging.
Parasites are vastly more prevalent than most people in modern, sanitary, medicated societies realize. Studies show that over half the biomass in a region may be parasitic.
Parasite frequently keep the host alive, but inhibit reproduction. This leaves the host alive, and competing with healthy members of its species for resources, but no capable longer reproducing. It's evolutionary dead weight.
Death is basically "turning it off and on again", just as you would do with a computer, and for very similar reasons. It clears the accumulated parasites and starts fresh.
This would also help explain why death is strongly conserved.
Also relevant to the article is: https://en.wikipedia.org/wiki/Antagonistic_pleiotropy_hypoth...
I don't know how the antagonistic pleiotropy theory is doing. If true it would be a satisfactory explanation from an evolutionary point of view but I recall that it had some problems.
Otherwise I don't find the other evolutionary explanations of programmed aging to be satisfactory, especially when you consider that genes are selfish and act on the individual rather than population level.
Perhaps reproductive aging (egg quality) is the ultimate limiter, and then overall aging is adaptive downstream of that because hunter-gatherer families benefit (in terms of evolutionary fitness) from fewer old people to increase the percentage of people at reproductive age? That would fit the modern evidence of early egg freezing significantly increasing reproductive success in older women, showing that the problem of fertility decline by age is primarily cellular.
Or perhaps the aging mechanism is leftover from pre-human ancestry and there simply wasn't enough time in our evolutionary history for humans to evolve longer lifespans, maybe because it's slightly helpful but not nearly as helpful as other traits like intelligence, and lifespan is hard to improve via genetic adaptation due to bottleneck effects?