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What Doesn’t Kill Me Makes Me Stronger

joshmitteldorf.scienceblog.com

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Re: What Doesn’t Kill Me Makes Me Stronger

#61

Post by Umn55 »

drcomputer wrote: post #47
soneca wrote: post #42

Earlier quoted context omitted.

I'm way out of my league here, but what if aging is just the way to evolve and adapt. If there were no natural deaths, beings with the same genes would be around forever, with no possibility for its species to adapt to a new environment. Any reproduction would be just creating more competition for resources if one expect to live forever. So there would be no deaths, but also no births, no mutations. If there was no d…

Yea, coming from the background assumption of "everything comes from the same thing", it seems more interesting to me that we have consciousness to experience, rather than the curiosity that we age and die. Age and death are phenomena we observe of ourselves, a thing that is constantly changing yet fundamentally the same thing. It's a philosophical quirk, but it really depends on your existential and universal (philo…

>it seems more interesting to me that we have consciousness to experience,

Everything that is alive has some level of "consciousness" aka some ability to sense, detect, and adapt to it's environment. The idea that consciousness is "special" and "unqiue" is the big lie. If knowledge is unified, then that means the same is true for the universe, since what we call "knowledge" is in fact the universes structure directly. Like your hand, your car, etc. What we call "knowledge" is our representations (symbolic languages like math, english, etc). We confuse our symbols with reality.

It's not that knowledge is "provisional" (aka the structure of the universe is the truth, hence not provisional), it's that our current abstract representations of it is.

Re: What Doesn’t Kill Me Makes Me Stronger

#62

Post by makeset »

gweinberg wrote: post #59
geoka9 wrote: post #8

Earlier quoted context omitted.

Also: "Walking around with a 40-pound backpack has the opposite effect of carrying an extra 40 pounds of belly fat." Actually walking around with a 40-pound backpack is a bad idea, as compared to carrying the weight at the level of your belly (all other things being equal) because the risk of back damage is much higher.

How about wearing a diver's weight belt? The weight is all at your hips and is more or less equally distributed between front and back.

Completely different physics, because buoyancy cancels out gravity. The weight belt is distributed around your center of mass because it has different buoyancy (higher density) than you, but subject to the same gravity, and you don't want it affecting your orientation underwater.

Re: What Doesn’t Kill Me Makes Me Stronger

#63

Post by mitteldorf »

abandonliberty wrote: post #19

A lot of this makes sense in the new deterministic model of aging. It argues that aging is not a collection of mutations, the old/popular model, but instead a programmed outcome of our genes that never experienced selective pressure. We are like a building, but the builders never know when they are done and eventually start doing counterproductive work that destroys us. Kicking in a response to injury or pathogen may…

Take a look at the works of Mikhail Blagosklonny. His view of aging and hormesis is just what you describe. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3249451/

(I'm not endorsing this view - I believe aging is programmed, largely based on the fact that genes for aging have been conserved since the dawn of eukaryotic life, i.e., cells that have a cell nucleus.)

Re: What Doesn’t Kill Me Makes Me Stronger

#64

Post by mitteldorf »

ytturbed wrote: post #40

>If animals eat all the food that is available to them and reproduce as fast is they are physically capable, then the environment will be denuded, the next generation will starve, and the species will face extinction. All animal species are evolved to avoid this Isn't this a Tragedy of the Commons? Won't genes that cause individuals to eat more and reproduce more quickly than fellow members of their species confer a…

Tragedy of the Commons is exactly right. Yes, the genes spread through the gene pool, but then the population goes extinct very quickly because there's a huge population and nothing to eat. This is the most powerful form of group selection, and it was first described by Michael Gilpin, http://press.princeton.edu/titles/663.html

Re: What Doesn’t Kill Me Makes Me Stronger

#65

Post by mitteldorf »

rdlecler1 wrote: post #17

To quote Dobzhansky, this is all becomes obvious in the light of evolution. A challenging environment removes those cells that accumulate mutations. (i) In challenging or resource constrained environments mutated cells tend to behave more aberrantly and our immune system responds by attacking them (this is why radiation therapy works). (ii) Mutated cells will be more prone to pathogenic infection. In either case, we…

There is no "natural selection" within an individual body, within an individual lifetime. Yes, there are some cells that continue to live and others that continue to die. But the cells are not competing, with the fittest winning out. Rather the whole scheme is orchestrated centrally for the good of the genome (which is the same in every cell).

Re: What Doesn’t Kill Me Makes Me Stronger

#66

Post by mitteldorf »

Qwertious wrote: post #35
deepakjc wrote: post #7

If this is true... then I need to rethink a lot of my life choices... what is actually good for me? Would love to hear the opinion of doctors/scientists on this...

I would be very, VERY sceptical - the moment he brought in evolution, he argued a theory based on (and nigh-identical to) group selectionism. Except group selectionism has been thoroughly debunked, to the point where he might as well have been spouting Lamarckism - read "The Selfish Gene", by Richard Dawkins. Put simply, you can't just jump from looking at individual survival to looking at a group's survival, because…

The Selfish Gene was a phase in our understanding of evolution. The mainstream now agrees that evolution is a whole lot more complicated than that. It's still true that "group selection" is a dirty word to a majority of evolutionary scientists, but this is shifting pretty fast - much less true than it was 10 years ago. Take a look at the works of David Sloan Wilson. I recommend his book, Unto Others. http://www.hup.harvard.edu/catalog.php?isbn=9780674930476

Re: What Doesn’t Kill Me Makes Me Stronger

#67

Post by ajcarpy2005 »

This is all based on the ability of the organism to strongly adapt. In order to do this, they need enough energy (calories) and micronutrients. I assume the organisms studied in labs for the ability to adapt to these stressors, are (outside of calorie restriction or related studies) well-fed...

Humans are often not so well-fed, at least not nutritionally.

Re: What Doesn’t Kill Me Makes Me Stronger

#68

Post by rdlecler1 »

mitteldorf wrote: post #65
rdlecler1 wrote: post #17

To quote Dobzhansky, this is all becomes obvious in the light of evolution. A challenging environment removes those cells that accumulate mutations. (i) In challenging or resource constrained environments mutated cells tend to behave more aberrantly and our immune system responds by attacking them (this is why radiation therapy works). (ii) Mutated cells will be more prone to pathogenic infection. In either case, we…

There is no "natural selection" within an individual body, within an individual lifetime. Yes, there are some cells that continue to live and others that continue to die. But the cells are not competing, with the fittest winning out. Rather the whole scheme is orchestrated centrally for the good of the genome (which is the same in every cell).

Actually it's called somatic evolution. And there is no central orchestration. When cells start to mutate they no longer share the same genome and it's typically in the organism's interest to remove those cells because they can lead to mutation.

Re: What Doesn’t Kill Me Makes Me Stronger

#69

Post by TylerJay »

soneca wrote: post #42
TylerJay wrote: post #29

I'm not buying the Demographic Theory of Senescence. > Aging is nature’s way of leveling out the death rate, assuring that we don’t all die at the same time. Aging puts our deaths on an individual schedule so we can die at different times; other causes of death tend to kill everyone or no one. It's a magical "group selection" hand-wavy argument—it sounds nice and is kind of heart-warming, but when making an evolution…

I'm way out of my league here, but what if aging is just the way to evolve and adapt. If there were no natural deaths, beings with the same genes would be around forever, with no possibility for its species to adapt to a new environment. Any reproduction would be just creating more competition for resources if one expect to live forever. So there would be no deaths, but also no births, no mutations. If there was no d…

Hey, sorry for the delay on this. That's not quite how natural selection works, but it's a very common line of thinking. When making an evolutionary argument, you can't make "top down" arguments. You have to look at it from a "bottom up" perspective.

Lets analyze the scenario where individuals don't die by aging. So we have some members of the species from generation 1 who grow up, then reproduce. In generation 2, there are some that have mutations that make them more suitable for the environment and some that make them less suitable. The less suitable ones are outcompeted and don't survive, the normal ones mostly group up to survive, and the ones with beneficial mutations outcompete all the others, leading to the deaths of some of the ones with the "original" genes, and procreate. This then happens again and again with beneficial mutations and they eventually becoming ubiquitous in the population.

There's just no way that an individual member of the species with a mutation that gives it a definite lifespan has a fitness advantage over the others, all else being equal. What's more likely is that immortality is not necessary to pass on genes, so it simply never developed because it would involve many complex systems, the individual components of which would not have conferred enough of a fitness advantage on their own to become universal in a population. And since the natural environment is harsh and predatorial, most animals don't die of old age anyway, which again limits the usefulness of an unlimited potential lifespan.

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