It's sad to imagine a day when Peter Thiel, Donald Trump, the Koch brothers, Fidel Castro can live forever. Even non-evil billionaires like Bill Gates living forever could be tragic, in that it greatly reduces the motivation for significant philanthropy.
If anything, once you've cheated death amassing more personal power might feel like a bit of a waste of time. Waste of time probably isn't the right phrase but you get my drift.
Well, at least we don't have to worry about Fidel anymore unless it somehow becomes retroactive.
Immortal of course doesn't mean impervious. A long, unaged, productive life span would still require food, water, shelter, and some amount of safety.
One of the most common (and usually loudest) arguments I hear against general species-wide immortality is the resource limitations of Earth. Well, if we can live for a thousand years or ten thousand years, what's the purpose of not traveling interstellar distances? The major limits are mostly the lifespan and related issues after all. The rest is mostly engineering. We're good at engineering our surroundings.
What do you mean? Sure there isn't a goal, but it's also true that some things tend to lead more success for a species and thus lead to the species with those traits dominating. Thus it's good from an evolutionary standpoint. Am I missing something?
Ok, I don't see how "one species dies and another lives" represents anything that is 'good'. It's just one way things could be. They could be other ways, and evolution doesn't show any preference for any of them.
What you're missing is that 'good' is defined with respect to a goal. From an evolutionary standpoint (whatever that really is), the complete extinction of all life is just one possible way things could be and it is as good as any other way things could be. From a human perspective, this is awful. As is any future where humans don't exist.
I think you've fundamentally misunderstood m3ta's comment.
You seem to have understood it as: "A species dying off very easily is sometimes a good thing for evolution." In response to this, your response is justified.
When in fact, what m3ta is saying is: "Members of a species dying very easily is sometimes an evolutionary advantage for that species." In response to this, your response is a non-sequitur.
It might seem that way, but there is actually a large caloric penalty to longer active lifespans. Birds live longer than mice because they have fewer predators but also because birds spend a lot of energy ensuring a longer lifespan. From an evolutionary perspective very old means very well adapted, so it is a useful benchmark.
Yup. I'm of the opinion that aging just is a "feature" of evolution. A population with aging has a significant fitness advantage over a population without aging so its not surprising that everything ages (the next generation is almost always more fit than the previous gen so the faster a population transitions to the next gen the more fit it is). But if aging just is a trait rather than some inevitable result of entropy, it leads one to be optimistic for reversing aging at least in principle.
Well the issue is whether a gene survives. Sometimes the individual is a good proxy for this, sometimes the population. Sometimes you just gotta consider the dynamics of a gene in a sea of other genes.
In the case of a supposed aging gene, consider that genes themselves preferentially want to exist in more fit organisms. If a gene could somehow manage this (i.e. be embodied with more fit genes), it will itself spread. But this is exactly what an aging gene does! Consider how an advantageous gene spreads through a population. This spread is a function of the number of generations that have passed. So a gene that could speed up the passing of generations will increase its own likelihood of existing in more fit organisms (increasing its own fitness), as advantageous genes within the population spread faster and are more frequently "paired up" with the aging gene. But the subpopulation with the aging gene is more fit than the subpopulation without it since the time for advantageous genes to spread is decreased, and so the aging population overtakes its counterpart.
I don't think this is correct. I've never heard of any evidence for pro-aging genes, but I have read molecular biology rebuttals against this theory (Stephen Jay Gould or perhaps textbook sources, though unfortunately I can't recall well enough to cite them).
You don't need extra genes or information to prefer organisms that age out of reproductive fitness. If advanced age during reproduction confers lower fitness, then the offspring are automatically less fit. While you could argue that there would be a competition for resources amongst the young offspring, this isn't much different than other scenarios that produce less fit or disabled offspring.
True, you don't need extra information to prefer organisms that age out of reproductive fitness, but you might need extra information to ensure a timely death. It remains to be seen whether aging is just due to entropy or that regenerative processes are programmed to stop after a certain amount of time. Programmed death confers very specific fitness advantage to one's offspring as you're no longer competing with them for resources.
The sharing of genes within a population creates a nice analogy between the population and a single organism. Programmed death for members of an organism is a standard feature of evolution. It's not implausible that such a feature exists at the level of population as well.
In many cases, it might matter much more. There are many species of animals that reproduce mostly within their own group. Group selection effects are much more pronounced in these species.
Aging as a feature doesn't make sense to me. It seems more likely to me that immortality simply hasn't been 'cracked' yet, intelligence that could create immortality would seem more likely to evolve first than immortality itself.
You have to get so many things just right for immortality to 'work', i.e. to actually be useful in a survival context. It does no good for creatures to not age if they lose a significant amount of viability.
But real immortality in the complete reversal of aging, I think would be an immense advantage. Instead of having to teach your young over a very short period of time the tricks they need to be viable adults, creatures could super-specialize. One creature could supply all the food needed for a huge colony. They'd just get better and better at exploiting their niche and other creatures could find other niches.
I think if intelligence hadn't 'gotten there first', immortal creatures would be running the show.
Against a really clever predator, perhaps with wings? Against accident and illness? Against a change in circumstance such that those overspecialized strategies no longer work sufficiently well or at all?
Trained up by whom? All that's left of the colony's institutional knowledge on the subject of provisioning is an owl pellet's worth of tiny bones and hair.
With immortality, institutional knowledge doesn't have to go away. Everybody can know everything, and the specialist that has all the experience dies, then a new one can just be selected, and the whole colony can pick up the slack until the new specialist is experienced enough to do it all himself.
Your experience could serve as limitation to your view of the world. Younger ones without the baggage of experience, has greater chance of discovering new approaches. Due to this, population with changing generations, might be more intelligent than one without these clean slates.
> In many of these experiments, older mice that received younger blood saw either slight or no significant improvements compared to old mice with old blood. Young mice that received older blood, however, saw large declines in most of these tissues or organs.
> The researchers think that many benefits seen in old mice after receiving young blood might be due to the young blood diluting the concentration of inhibitors in the old blood.
How can these things be compatible? If it were diluting the inhibitors, that should have shown up as an improvement in the old mice, no?
My guess is that the effect of the inhibitors is not linear with concentration.
Imagine that the effective (deleterious) dose of these inhibitors is, say, 10% of the amount found in old mice. So an equal exchange between two mice is enough to provide an effective dose to the young mouse, but not enough to eliminate an effective dose to the old mouse.
If this inhibitor hypothesis were true, an experiment could be set up to determine which component/combination of components in the old-blood actually plays the inhibitor role, with injection of separated part by component of old-blood into the young mice, more or less like a binary search. After knowing the exact combination, it would be much easier to target the inhibitor itself.
I had to do exactly these surgeries on rats for a few years as a lab tech.
Also did some other fun things such as mass killings of rats using mini-guillotines, harvesting bones and doing amateur brain surgeries while other rats watched restlessly and anxiously peeped from the smell of blood.
This kind of stuff can mess with your sanity. For me it was a converse of how serial killers injure animals when they were children.
They probably don't have much choice for where they did it. The animals likely couldn't see it, and the stress levels were probably minimal. It's not likely to be enough to harm the experiment.
While, yes, everything can be a variable, the effect wouldn't be big. I imagine the person running the lab had done this before and has gotten good results: rats are expensive and a hassle to keep. If his experiments had been 'screwed over' because of practices like that, his PI probably wouldn't be able to gather enough useful data to afford funding for animal use.
Most likely they grab a box of 2-3 rats, take it to a procedure room, and perform surgeries on all the rats in sequence. It's a bit on the lazy end, since you could always do a surgery on one rat, take it back to the housing room, and get the next one. Some labs do not permit animals to observe another's surgery or euthanasia. The rules are more lax for Mus musculus and Rattus rattus, than for other mammalian species, in the US.
> Fetal cells migrate into the mother during pregnancy. Fetomaternal transfer probably
> occurs in all pregnancies and in humans the fetal cells can persist for decades.
> Microchimeric fetal cells are found in various maternal tissues and organs including
> blood, bone marrow, skin and liver. In mice, fetal cells have also been found in the
> brain. The fetal cells also appear to target sites of injury. Fetomaternal
> microchimerism may have important implications for the immune status of women,
> influencing autoimmunity and tolerance to transplants.
"Importantly, our work on rodent blood exchange establishes that blood age has virtually immediate effects on regeneration of all three germ layer derivatives."
This seems like this is a misleading way for these researchers to present their results.
Yes, there study did show that young blood can not stop the effects of old blood.
However if someone were going to get transfused with young blood the amount of old blood in their system would decrease, so then, presumably, you would see anti-aging effects.
I don't know why they didn't present the research like that. It seems like they don't want to say it or I'm just missing some logical step in my thinking.
They didn't like how the previous results were sensationalized in the media so they are proactively downplaying anything that could be used as a sound bite.
63 comments
[ 34.9 ms ] story [ 1982 ms ] threadImmortal of course doesn't mean impervious. A long, unaged, productive life span would still require food, water, shelter, and some amount of safety.
One of the most common (and usually loudest) arguments I hear against general species-wide immortality is the resource limitations of Earth. Well, if we can live for a thousand years or ten thousand years, what's the purpose of not traveling interstellar distances? The major limits are mostly the lifespan and related issues after all. The rest is mostly engineering. We're good at engineering our surroundings.
What you're missing is that 'good' is defined with respect to a goal. From an evolutionary standpoint (whatever that really is), the complete extinction of all life is just one possible way things could be and it is as good as any other way things could be. From a human perspective, this is awful. As is any future where humans don't exist.
You seem to have understood it as: "A species dying off very easily is sometimes a good thing for evolution." In response to this, your response is justified.
When in fact, what m3ta is saying is: "Members of a species dying very easily is sometimes an evolutionary advantage for that species." In response to this, your response is a non-sequitur.
In the case of a supposed aging gene, consider that genes themselves preferentially want to exist in more fit organisms. If a gene could somehow manage this (i.e. be embodied with more fit genes), it will itself spread. But this is exactly what an aging gene does! Consider how an advantageous gene spreads through a population. This spread is a function of the number of generations that have passed. So a gene that could speed up the passing of generations will increase its own likelihood of existing in more fit organisms (increasing its own fitness), as advantageous genes within the population spread faster and are more frequently "paired up" with the aging gene. But the subpopulation with the aging gene is more fit than the subpopulation without it since the time for advantageous genes to spread is decreased, and so the aging population overtakes its counterpart.
You don't need extra genes or information to prefer organisms that age out of reproductive fitness. If advanced age during reproduction confers lower fitness, then the offspring are automatically less fit. While you could argue that there would be a competition for resources amongst the young offspring, this isn't much different than other scenarios that produce less fit or disabled offspring.
The sharing of genes within a population creates a nice analogy between the population and a single organism. Programmed death for members of an organism is a standard feature of evolution. It's not implausible that such a feature exists at the level of population as well.
https://en.wikipedia.org/wiki/Evolution_of_ageing
None of these has been proven or widely accepted, and the entire class of theories has many rebuttals. They are interesting to consider, though.
You have to get so many things just right for immortality to 'work', i.e. to actually be useful in a survival context. It does no good for creatures to not age if they lose a significant amount of viability.
But real immortality in the complete reversal of aging, I think would be an immense advantage. Instead of having to teach your young over a very short period of time the tricks they need to be viable adults, creatures could super-specialize. One creature could supply all the food needed for a huge colony. They'd just get better and better at exploiting their niche and other creatures could find other niches.
I think if intelligence hadn't 'gotten there first', immortal creatures would be running the show.
We call this a "single point of failure".
Everybody becomes T-shaped.
> The researchers think that many benefits seen in old mice after receiving young blood might be due to the young blood diluting the concentration of inhibitors in the old blood.
How can these things be compatible? If it were diluting the inhibitors, that should have shown up as an improvement in the old mice, no?
Imagine that the effective (deleterious) dose of these inhibitors is, say, 10% of the amount found in old mice. So an equal exchange between two mice is enough to provide an effective dose to the young mouse, but not enough to eliminate an effective dose to the old mouse.
keyword is 'slight' improvements. it's a poorly written sentence.
That's terrifying.
Also did some other fun things such as mass killings of rats using mini-guillotines, harvesting bones and doing amateur brain surgeries while other rats watched restlessly and anxiously peeped from the smell of blood.
This kind of stuff can mess with your sanity. For me it was a converse of how serial killers injure animals when they were children.
Still have nightmares sometimes.
While, yes, everything can be a variable, the effect wouldn't be big. I imagine the person running the lab had done this before and has gotten good results: rats are expensive and a hassle to keep. If his experiments had been 'screwed over' because of practices like that, his PI probably wouldn't be able to gather enough useful data to afford funding for animal use.
What a sad situation to be caught up in.
https://en.wikipedia.org/wiki/Parabiosis#Parabiotic_experime...
http://blogs.discovermagazine.com/80beats/2011/11/21/helpful...
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2633676/
Yes, there study did show that young blood can not stop the effects of old blood.
However if someone were going to get transfused with young blood the amount of old blood in their system would decrease, so then, presumably, you would see anti-aging effects.
I don't know why they didn't present the research like that. It seems like they don't want to say it or I'm just missing some logical step in my thinking.
My personal theory is older organisms get colonized by all kinds of bacteria that might trigger or speed up the breakdown the body.