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Comments |
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 | Thursday, June 25, 2009 at 4:28:07 mst
Comment ID: #1
Name: Tom Rowland
E-mail: www.atlasfan(at)earthlink.net
This is indeed a tragedy and, today, correct me if I'm wrong,avoidable. In that context, as you point out, is it really "caring" and Loving" to bring such a child into the world? |
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| Thursday, June 25, 2009 at 4:58:35 mst
Comment ID: #2
Name: Dan
Some of the comments on the article scare me. For instance:
"WOW! What a blessing these parents have received. A baby to cuddle and to give unconditional love for all these years. God has truely blessed them. She seems to be a happy child so i see no big deal about the whole situation other then she truely is a gift from God. I wish the family well. May GOD bless you." |
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| Thursday, June 25, 2009 at 5:34:47 mst
Comment ID: #3
Name: KPO'M
E-mail: ka84796(at)comcast.net
Tom, I don't think the parents realized at the time the child wouldn't develop cognitively or physically. If by "preventable," you mean that the parents could have withheld treatment for her illnesses that's also a difficult proposition. Perhaps scientists will discover a treatment that will enable her to develop. If she still has a pre-pubescent brain, she may yet be capable of learning skills to live an independent life. They also have legal obligations, as well. Presumably, she'll be declared incompetent at 18 and her parents named as her custodian. It is an interesting legal question as to what happens if she outlives her parents. Perhaps one of the sisters would offer to take car of her (though, if she is truly in a state where she resists physical, as well as cognitive aging, she may well outlive them, too), though under no circumstances should they be forced to.
From a moral perspective, I think there is a natural desire of parents to want to protect their children. In Brooke's case, she's a perpetual child. I'd think at some point (which probably differs from person to person), such a thing becomes a significant burden. I wouldn't be so quick to disparage the "warm and fuzzy" feelings of the parents. They are the ones living through this unfortunate situation and it's difficult for us to know truly how we'd react if we were in the same situation. |
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| Thursday, June 25, 2009 at 9:53:09 mst
Comment ID: #4
Name: ECS
E-mail: alliesmom97(at)yahoo.com
To Tom:
First, I admit I am absolutely NOT in favor of abortion, althoguh I understand people have persoanl reasons for such a choice. But in this case, if you do some research you will learn the parents were NOT aware that Brooke would have these issues. The only "clue" if you will, during the pregnancy was that intrauterine growth was inconsistent...she would not grow one month, but would the next. To this day the doctors have not found anything "wrong" with Brooke. Her parents have said the case baffles all the doctors. Prenatal genetic testing wouldn't have revealed anything. In fact, although Brooke was a little early and small (4 lbs) at birth, with a hip condition requring surgery,she was nearly a year old before if became clear something was really not right. So to accuse these parents of delibertely bringing "such a child" into the world is unnecessarily cruel. And, as she is now here, what would you have them do? |
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| Thursday, June 25, 2009 at 12:27:43 mst
Comment ID: #5
Name: Lemuel
E-mail: synthesist(at)ymail.com
I can't even *approach* the moral implications of this quite yet ... just the mere fact of it is mind-blowing.
"That Brooke is in her mid-teens is so mind-boggling that if another mother with a toddler asks Greenberg how old Brooke is, she usually doesn't try to explain." No kidding ... if I ran into a woman who said her infant was legally old enough to DRIVE, I'd wonder about her mental health.
"For more of Brooke's story, watch the documentary, 'Child Frozen In Time,' Sunday, Aug. 2 at 10 p.m. on TLC." Yeah, I'll definitely be watching that. This is about as intriguing a thing as I've ever heard about.
Does the other Dr. Hsieh have any insight? |
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| Thursday, June 25, 2009 at 12:51:05 mst
Comment ID: #6
Name: Paul
E-mail: ultraupper(at)gmail.com
"And, as she is now here, what would you have them do?"
That question answers itself: Infanticide.
There is a certain species of rationalist that doesn't understand the principle that a concept is not equal to its definition. They would judge this child as not really human, so it shouldn't be a crime to kill it to be rid of the inconvenience of its existence. |
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| Thursday, June 25, 2009 at 13:05:13 mst
Comment ID: #7
Name: Steve D'Ippolito
It'd be more appropriate, I think, to have titled this "The Hell Of Perpetual Infancy" -- "youth" to me conjures up an adolescent or even an early-20s age range, which would not be Hell unless of course you couldn't learn from your mistakes (as in "youth is wasted on the young"). |
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| Thursday, June 25, 2009 at 13:26:50 mst
Comment ID: #8
Name: madmax
If she outlives her parents and, say, none of her relatives wanted to care for her, would it be the responsibility of the government to care for her? Would that be a legitimate action of government? |
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| Thursday, June 25, 2009 at 13:34:15 mst
Comment ID: #9
Name: Adam Spong
As a laughable side note:
I clicked on the link contained in the article's passage, "aged in the conventional sense," thinking I'd perhaps get an article with some general information on the aging process.
Instead, it links to an article with the subtitle, "Altruistic activities could cut the death risk in half, study finds."
http://abcnews.go.com/Health/Healthday/Story?id=7540441&page=1
Evidently ABC considers that idea to be the most essential point to convey to anyone interested in the science of aging.
The irony though is that the lead researcher actually gives a rational explanation for the results which is basically the opposite of the spin given by the reporter's title. From the article:
"He said that volunteering also seems to be associated with "self-efficacy" or a belief in your own abilities to accomplish certain tasks. "Staying healthy requires doing different things like quitting smoking or losing weight," explained Lee, and people who have higher self-efficacy may believe themselves more capable of accomplishing those tasks."
Who knew that self-efficacy and a belief in your own capability were actually life-promoting??? |
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| Thursday, June 25, 2009 at 15:14:23 mst
Comment ID: #10
Name: Adam Spong
I found the following article on this "teenage baby" to be somewhat more substantive, scientifically.
http://www.newscientist.com/article/dn17379-teenage-baby-may-lack-m ...
It also, however, brings up a potentially misleading aspect of this bizarre case--the question of a "master aging gene."
The idea of a master gene for aging usually entails the view that aging was positively selected for in evolution, such that the aging process is actively imposed on us by our genes because it confers some adaptive advantage. Such theories typically rely on "group selection" as an evolutionary theory and the idea that aging exists because it is good for the species (e.g. because it prevents overpopulation).
This view is rejected by the overwhelming majority of aging researchers. The evidence abundantly supports the conclusion that there is no master aging gene--not if that is understood to mean a gene that turns on aging as an adaptive program.
In fact, the prevailing evolutionary theories of aging are based on an essentially opposite idea: Not that aging is selected for but rather that there's no evolutionary reason for selecting against it. To simplify: the force of natural selection drops off as individual organisms live longer, such that there's no payoff from the genes' perspective in developing mechanisms for keeping an individual organism alive. Past a certain point, an animal is likely to be killed off simply by environmental hazards or predators before it lives long enough to benefit from genes that would keep it alive longer via an alteration to its aging process. Aging, on this type of theory, is the result of (probably a great deal of) deficiencies and vulnerabilities in the organism that evolution doesn't bother to fix.
http://www.rwalkerphd.com/
The irony here is that the researcher on this "teenage baby" case, Richard Walker, holds an evolutionary view of aging which is fully consistent with the mainstream view I've described. Judging from his website, I presume that he would repudiate the idea of aging as selected.
In other words, the reporting in the NewScientist article is misleading, and it misrepresents the view of the scientist they're quoting.
If there is in fact a single gene responsible for this girl's condition, it is far more likely to represent some kind of "master development gene," not a master gene for aging.
That doesn't mean, however, that it isn't potentially relevant to understanding aging or even to intervening in the process. It may well be important, and its an apparently fascinating case. But some context is needed, lest we have unwarranted hopes for some one gene we can just switch off for the fountain of youth. |
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| Thursday, June 25, 2009 at 21:00:19 mst
Comment ID: #11
Name: Anthony
I think the worst part would be the uncertainty. If the parents knew what was going to happen with their child it'd be easier to deal with.
I hope the "fascinated" scientists are helping with the bills. |
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| Thursday, June 25, 2009 at 23:07:14 mst
Comment ID: #12
Name: Doug H.
E-mail: radiotheatre(at)gmail.com
Is the "baby" likely to live any longer than an average person? And is she ever going to develop? Those seem to be the most important questions at this time, with regards to the "mystery". |
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| Friday, June 26, 2009 at 0:14:35 mst
Comment ID: #13
Name: Adam Spong
The obvious thing to do is to find the mutation (if that's the cause), and then knock out the homologous gene in mice. Then you can look at their lifespan, etc.
Although, as I said above, I suspect that this has strictly more to do with development than with aging as such, there is a phenomenon in the roundworm C. elegans that's worth mentioning.
When environmental conditions are unfavorable (e.g. food is scarce), these worms can greatly extend their lifespan by entering a form of developmental arrest that keeps them stuck at a larval stage. This lets them ride out the harsh conditions before they go on to become adults. It is probably only a crude and superficial parallel to connect that phenomenon to the case here, but it might turn out to be relevant somehow.
In the case of C. elegans, you can mutate the same genes that control this larval arrest to cause substantial life extension *without* any developmental problems. The genes here are involved in the insulin-like signaling pathway, and a large body of evidence indicates that the same pathways (insulin and insulin-like growth factor signaling) can regulate aging in mammals as well.
Mice with mutations in certain genes in these pathways have an extension of maximum lifespan (up to a 50% increase).
So the point is that there is a precedent for the phenomenon of genes that can cause a halt in development in some animals also being involved in regulating aging.
But it's far too early to draw any conclusions based on that relating to this one strange case. |
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| Saturday, June 27, 2009 at 1:09:07 mst
Comment ID: #14
Name: Jim May
E-mail: seerak(at)gmail.com
Adam Spong writes:
"Such theories typically rely on "group selection" as an evolutionary theory and the idea that aging exists because it is good for the species (e.g. because it prevents overpopulation)."
The way I looked at the possibility of mortality as being selected *for*, is that mortality serves the same role as sexuality: it helps maintain a certain rate of genetic turnover and variability in the population.
Where this becomes an advantage is in the speed with which a species can adapt to environmental change. Consider what tenure does to university departments, and then consider what would happen if those professors were immortal... the ultimate tenure. Talk about frozen! From an evolutionary standpoint, immortality would always select for those individuals whose particular genetic combination was ideally suited for the **current circumstances**. It would also select for the mature against the young, with only the most perfectly adapted of the latter surviving to replace those lost to accidents, predation or disease.
The problem with that is that the resulting genetic makeup of the population would become extremely narrow, extremely well suited for current conditions at the consequence of being ill-suited for any other environment -- or in a changed environment. When the environment shifts, as it always does, that adaptation suddenly becomes a liability. The die-off is sharper, potentially extinguishing. The large die-offs observed in history, such as that of the dinosaurs, were an example of what happens when a big change comes: the life forms that were highly specialized and adapted to the relatively narrow set of climatological variables of their day could not survive when the change was *global*.
Compare that with a population where there is much more genetic variation at a given time, due to mortality-induced turnover. The population as a whole wouldn't be as well-adapted to the current environment; there would be a varying range of misfits with various degrees of unfitness for the current environment, but who nonetheless survive because of the death-by-aging of more well-adapted competitors.
From this, you get two effects: First, is that the misfits may migrate to where they are better able to compete -- providing diversity of location, which enhances survival of the species should the main home be altered drastically. Second, and more important: if the environment changes in such a manner that the "mainstream" genetic variants are suddenly at a severe disadvantage, there is an increased chance that among the misfits will be the combinations and mutations that are no longer a liability, but are now a significant **advantage** in the new circumstances. If those variants had not existed or survived, extinction of the suddenly mal-adapted species would have been a much more likely outcome.
All of this is based on the observation on my part, of two things in nature: that specialization (adaptation to particular circumstances) and adaptability always seem to be inversely related, and that both death and sexual reproduction have the same effect: to increase variability by forcing the random recombination of genes (via sexuality) and a minimum rate of genetic turnover (via mortality). |
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| Saturday, June 27, 2009 at 8:39:15 mst
Comment ID: #15
Name: Andrew Dalton
E-mail: andrew.s.dalton(at)gmail.com
URL: http://witchdoctorrepellent.blogspot.com
I am skeptical of any theories that require the "good of the species" to be a causative factor in evolution. By what mechanism could natural selection (that is, differential rates of survival and reproduction, which necessarily also includes competition *within* a species) achieve this end?
I lean toward the view that there are are basic physical limits on the durability of multicellular living organisms, and that natural selection can only incrementally modify this. As one piece of evidence, consider that different animal species have approximately the same number of heartbeats in their lifetimes:
http://www.sjsu.edu/faculty/watkins/longevity.htm
(Scroll about 3/4 the way down.) |
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| Saturday, June 27, 2009 at 9:36:43 mst
Comment ID: #16
Name: Anthony
"The way I looked at the possibility of mortality as being selected *for*, is that mortality serves the same role as sexuality: it helps maintain a certain rate of genetic turnover and variability in the population."
Isn't immortality contradictory to the second law of thermodynamics? |
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| Saturday, June 27, 2009 at 9:56:43 mst
Comment ID: #17
Name: Andrew Dalton
E-mail: andrew.s.dalton(at)gmail.com
URL: http://witchdoctorrepellent.blogspot.com
"Isn't immortality contradictory to the second law of thermodynamics?"
No, not unless you mean living unconditionally and literally forever (beyond the heat death of the universe).
Many single-celled organisms are "immortal" in the sense that they do not age; they continue metabolizing and dividing so long as they have a food source.
http://en.wikipedia.org/wiki/Biological_immortality |
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| Saturday, June 27, 2009 at 10:10:04 mst
Comment ID: #18
Name: William H Stoddard
E-mail: whswhs(at)mindspring.com
URL: http://whswhs.livejournal.com/profile
Jim,
When you say "Where this becomes an advantage is in the speed with which a species can adapt to environmental change. Consider what tenure does to university departments, and then consider what would happen if those professors were immortal... the ultimate tenure. Talk about frozen! From an evolutionary standpoint, immortality would always select for those individuals whose particular genetic combination was ideally suited for the **current circumstances**. It would also select for the mature against the young, with only the most perfectly adapted of the latter surviving to replace those lost to accidents, predation or disease," this sounds like an exaggerated version of what evolutionary geneticists call "r-selection" and "K-selection." r is the rate of reproduction; r-selected species have competition to produce as many offspring as possible, as fast as possible. K is biomass; K-selected species have competition to produce a large stable mature population that retains a lot of resources within itself. Think of grass versus trees, or mice versus elephants, or insects versus mammals. Grass sprouts up quickly when there's rain, or warm weather, or other favorable conditions, and produces a minimal weight of adult body tissue, and then produces lots and lots of seeds, scatters them widely, and dies; but trees live on over many years, with a huge weight of adult body tissue, continuously occupying a favorable place, and suppressing the growth of younger competitors by, for example, shading the ground. If you take K-selection beyond all realistic limits, you would get immortality, with a reproductive rate approaching zero. And this would work if you had a completely stable environment where there was nothing new to be discovered and no new resources to be exploited.
Elizabeth Moon, a science fiction writer I like, explores this in her Heris Serrano and Esmay Suiza series (http://www.amazon.com/Serrano-Connection-Suiza/dp/1416555951/ref=sr ... looks to be the complete set). She portrays a society that has highly effective life extension, and whose armed forces are struggling to cope with the fact that both admirals and chief petty officers are still on the job, and not ready to retire, even in their seventies and eighties, leaving no place for younger officers or enlisted men to be promoted into; her society *has not* resolved this problem, which makes the situation a dramatic one. |
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| Saturday, June 27, 2009 at 12:17:20 mst
Comment ID: #19
Name: Adam Spong
A clarification must be made on the issue of "immortality."
This is a perennial confusion of any discussion of life extension or of non-aging organisms:
Literal immortality (i.e. indestructibility) is entirely outside the realm of possibility, and is irrelevant to the issue of aging.
We are talking about animals which do not age, not animals which cannot die.
It is improper to speak of "mortality" as a synonym for aging, or of the evolutionary consequences of "immortality," as in Jim May's above post. These are inapplicable concepts in this context which severely obscure the issue. The correct terms here are "aging" and "non-aging" or some equivalent.
This distinction should be obvious, but the extent to which confusion on this point can derail debate on the question of life extention is incredible. |
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| Saturday, June 27, 2009 at 14:23:12 mst
Comment ID: #20
Name: Adam Spong
Andrew Dalton wrote:
"I lean toward the view that there are are basic physical limits on the durability of multicellular living organisms, and that natural selection can only incrementally modify this. As one piece of evidence, consider that different animal species have approximately the same number of heartbeats in their lifetimes"
This is essentially the "wear-and-tear" theory of aging, which has, with good reason, been abandoned by modern biogerontology.
(The idea of a finite number of heartbeats as an important common factor in aging is a particularly antiquated view without empirical justification. You might find some correlation there within a specific context, but it's not generally valid and a causal connection to aging as such does not exist.)
The wear-and-tear theory consists of the view that aging in an animal is very simply and directly analogous to the physical deterioration over time of a mechanical device like an automobile. It is merely a consequence of the progessive accumulation of damage from all the myriad physical insults and injuries sustained throughout life. Any machine, no matter how sophisticated, will break down over time. Aging, therefore, is an essentially inevitable outcome imposed on us by relentless laws of physics, and life could not have evolved to prevent it. (It follows that this type of theory often leads to the [very erroneous] conclusion that we humans can't do anything about aging either.)
The crucial fact overlooked by this view is that living organisms have an incredible capacity for self-organization and self-repair.
The reason that animals have (by and large) failed to evolve a non-aging state is not due simply to rigid physical limits on the durability of living bodies or on the ability to deal with damage. Modern evolutionary theory instead holds that the incentives to evolving extreme longevity (or negligible senescence, or the absence of aging) were lacking in evolutionary history. The evidence supports the conclusion that animal biology could in fact handle and repair the damage and deterioration of aging, effectively keeping even advanced and complex animal bodies functioning for extreme lengths of time, potentially into the indefinite future. Several examples exist of extant animal species which may in fact approach this state--the term "negligible senescence" was coined to describe these cases. See here:
http://www.agelessanimals.org/
There is a simple point to consider on this issue which I find particularly compelling. Our biology is perfectly capable of building--starting with the miniscule speck of a single cell--the vast and amazingly sophisticated mechanical integration that is the human body, with all its incomprehensible complexity of function sustained over decades. Given this immense developmental power, we should in fact be surprised that aging occurs at all, instead of taking for granted that wear-and-tear would inevitably break us. In other words, if our parts do wear out, why can't our cells just marshal that same capacity they have for building the machine in order to re-construct it on the same plan?
By analogy, it is harder to build a car in the first place than it is for the mechanic to keep it running. Further, we know that although the car will run down if left alone to deteriorate, as long as we continue to apply the resources, we can effectively keep it functioning indefinitely. Given the input of enough maintenance and money, people can keep cars from the 1920's in perfect working order. If a single cell can ultimately acquire enough resources from the environment to build a body built of a trillion cells, why can't our adult body simply allocate the resources it takes in to effect its upkeep?
So there's good reason to believe that animals *could have* developed without the necessity of aging, save for evolutionary incentives that made it not worth the trouble.
But more importantly for us than the question of evolutionary history is the fact that this argument for the non-inevitability of aging gives a strong cause for optimism when it comes to the possiblity of life-extension. Given that the restrictive, absolute physical limits on lifespan postulated by certain wear-and-tear theories do not exist, we can in fact intervene in the aging process through technology to extend our lives.
The possiblity of substantial human life-extension, perhaps within our lifetimes, is supported by many other lines of evidence, but these evolutionary principles regarding the source of aging in evolution--as well as the actual existence of negligibly senescing animals--provide a particularly encouraging case. |
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| Saturday, June 27, 2009 at 15:28:29 mst
Comment ID: #21
Name: Andrew Dalton
E-mail: andrew.s.dalton(at)gmail.com
URL: http://witchdoctorrepellent.blogspot.com
I'd like to see some evidence that the wear-and-tear theory has been abandoned (and also why), rather than accepting your say-so on the matter.
I'm also not particularly impressed by analogies. Many plausible-sounding, yet nevertheless completely wrong, arguments can be made by analogy. |
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| Saturday, June 27, 2009 at 17:26:59 mst
Comment ID: #22
Name: Anthony
Thanks for the clarifications, Adam. I have to say that I always took the "wear and tear theory" for granted, though I never thought that implied that we were powerless to reverse the effects.
Looking at the leading causes of death: heart disease, cancer, stroke, chronic lower respiratory diseases, accidents (unintentional injuries), and diabetes, they all seem to fit that description. Some body function wore out over time (or in the case of cancer and accidents, our luck ran out and we rolled snake-eyes), and while we know what happened and theoretically how to fix it, either we caught it too late, or it's too much effort to fix it all, or while we're trying to fix it we cut off circulation to the brain too long. If we had infinite (brilliant) doctors, an ER on every corner, unlimited organ donors (or some way to generate organs on demand), weekly full body scans, perfect diets, etc., I think most of us would make it well past 100, at which point the problems we don't yet understand would start popping up.
Which is where I stopped, right before Alzheimer's disease. I think we can eventually develop treatments for Alzheimer's disease too, though.
I guess I've ignored the non-lethal aspects of aging, but they seem to be of the same categories. |
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| Saturday, June 27, 2009 at 18:08:28 mst
Comment ID: #23
Name: Adam Spong
I'll have to refrain from attempting to present a survey of the field of evolutionary biogerontology.
However, I can point you to a useful website from the American Federation for Aging Research, an important private funding institution in gerontology.
This site gives a brief overview of theories of aging. It makes nicely the important distinction between the theories that deal with *why* we age and those that deal with *how* we age.
http://websites.afar.org/site/PageServer?pagename=IA_b_the_home
Of particular note is the page on the evolutionary senescence theory of aging, described as "the most widely accepted theory of aging."
This is the evolutionary theory I have described above.
http://websites.afar.org/site/PageServer?pagename=IA_b_the_evol_senesce
The AFAR site says of this theory that "[a]lthough many scientists believe the evolutionary theory of aging needs further refinement, most agree that it is currently the best explanation for why we and other organisms age."
As I argued above, the reason that aging occurs at all is *not* because wear and tear just assualts the durability of the organism, as a simple and irrevocable mechanical process. It is rather because evolution is blind to late-life fitness effects, and so doesn't bother to maintain individuals past a certain age (set by the context for particular species).
The various forms of damage that we incur throughout life may form a part of *how* we age, but the reason that evolution didn't build us to withstand or repair that damage has to do with "contingent" selective pressures, not with some insuperable barrier to lifespans imposed by mechanical forces.
Incidentally, the specific example, cited in a previous post, of a limit on the number of heartbeats is a very old version of the "rate of living" theory of aging, addressed and rejected here:
http://websites.afar.org/site/PageServer?pagename=IA_b_the_rate_living
The specifically modern, scientific claim about the relation of aging to heartbeat number is attributed to Max Rubner, working in the late 19th century. Evidence has not supported his theory.
As to the specific theory to which the term "wear and tear" was first applied, I will simply quote from the textbook "The Biology of Aging" by Robert Arking.
"The wear-and-tear theories of aging are probably the oldest precursors of the concept of failure to repair. These theories persist probably because they are unconsciously reinforced by our everyday observations. All organisms are constantly exposed to infections, wounds, and injuries that are likely to cause minor damage to cells and tissues and organs. Such structural erosion and minor injuries might contribute incidentally to an age-related decline in functional efficiency. August Weismann (1891) thought this gradual wearing down of the somatic cells as a result of use was the major cause of aging. Today we would strenuously disagree..." p.363
The book goes on to make the point that certain modern mechanistic theories of aging can be seen as conceptual descendants of the original wear and tear idea, if "wear and tear" is interpreted very loosely and updated by modern advances. The point to grasp here, however, is that these are *mechanistic* theories of aging--that is, they relate to *how* we age, not *why*.
The basic understanding of the evolutionary reason *why* aging occurs is one of the most important advances in aging research, and for science in general, of the last century. At least as far as the essential, foundational idea behind the evolutionary senescence theory, I regard this as an established scientific principle. |
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| Saturday, June 27, 2009 at 19:08:42 mst
Comment ID: #24
Name: William H Stoddard
E-mail: whswhs(at)mindspring.com
URL: http://whswhs.livejournal.com/profile
Adam,
A variant on wear and tear is the accumulative blood toxins theory. Robert Heinlein relied on it in his science fiction novel "Methuselah's Children," and it turns up in a villanelle by William Empson, whose alternating refrain lines are "Slowly the poison the whole blood stream fills. . . . The waste remains, the waste remains and kills." Both date to between the World Wars, which is when that theory seems to have been at its height of acceptance. |
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| Sunday, June 28, 2009 at 5:56:25 mst
Comment ID: #25
Name: Anthony
"As I argued above, the reason that aging occurs at all is *not* because wear and tear just assualts the durability of the organism, as a simple and irrevocable mechanical process."
What is the theory that wear and tear assaults the durability of the organism as a complicated and revocable mechanical process?
"It is rather because evolution is blind to late-life fitness effects, and so doesn't bother to maintain individuals past a certain age (set by the context for particular species)."
I don't see how that contradicts "that wear and tear assaults the durability of the organism as a complicated and revocable mechanical process".
"The point to grasp here, however, is that these are *mechanistic* theories of aging--that is, they relate to *how* we age, not *why*."
I don't see how one can distinguish "how" from "why" when it comes to the metaphysically given. Man evolved the way he evolved as a non-volitional process.
If people feel the need to cling to counterfactuals like "what would have happened if we had evolved in way X" on their way to the true question of "what will happen if we change our genes to give us X", I'm not going to complain. But personally, I prefer to skip that step. |
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| Sunday, June 28, 2009 at 6:28:50 mst
Comment ID: #26
Name: Andrew Dalton
E-mail: andrew.s.dalton(at)gmail.com
URL: http://witchdoctorrepellent.blogspot.com
"I don't see how one can distinguish "how" from "why" when it comes to the metaphysically given. Man evolved the way he evolved as a non-volitional process."
You can distinguish between fundamental causes versus effects (intermediate mechanisms). I'm pretty sure that this is the distinction that Adam is making.
For example, let's say that some part of aging can be attributed by experimental evidence to DNA damage. That knowledge alone wouldn't give you a fundamental cause of aging. One hypothesis could be that the damage is irreducibly stochastic (entropy-driven) and that there are insurmountable thermodynamic limits to how long the cellular repair mechanisms can keep the damage at bay. Another hypothesis could be that the repair mechanisms can actually succeed indefinitely, but that some genetic switch causes them to weaken in old age. These hypothesis have a different "why" to explain the same "how." |
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| Sunday, June 28, 2009 at 8:06:30 mst
Comment ID: #27
Name: Anthony
If man can step in and flip the genetic switch, then we are no longer talking about the metaphysically given. We have a choice, to flip the switch, or not to flip the switch. Of course we should hypothesize the results of doing so.
The manner in which we evolved is the metaphysically given. The fact that we evolved the way we did "could not have occurred differently or failed to occur" (http://aynrandlexicon.com/lexicon/metaphysical_vs_man-made.html). "Why" does not make sense, because there were no alternatives to choose from.
If you want to pretend the metaphysically given could have occurred differently, and then draw an analogy from that counterfactual to the present choices, it might mostly work in most cases. If you want to say "if beavers had built a dam here we wouldn't have a flooding problem" and then conclude by analogy that "if we build a dam here we won't have a flooding problem", I guess that's fine. But it's unnecessary. |
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| Sunday, June 28, 2009 at 8:12:21 mst
Comment ID: #28
Name: Andrew Dalton
E-mail: andrew.s.dalton(at)gmail.com
URL: http://witchdoctorrepellent.blogspot.com
Anthony -
I don't understand why this is difficult. The word "why" has different meanings depending upon context. Adam was clearly not talking about aging having a conscious purpose. |
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| Sunday, June 28, 2009 at 9:17:15 mst
Comment ID: #29
Name: Adam Spong
Anthony wrote:
"I don't see how one can distinguish "how" from "why" when it comes to the metaphysically given. Man evolved the way he evolved as a non-volitional process."
I am quite obviously not talking about some kind of mystical teleology here, so I will ignore that part.
"Why" and "How" are terms that have commonly been used in biogerontology to make a crucial conceptual distinction between types of theories of aging, as the American Federation for Aging Research site indicates:
http://websites.afar.org/site/PageServer?pagename=IA_b_the3_what
If you require clarification on this important point, I can suggest some literature in the field.
But here is example:
WHY, in terms of adaptive advantage, did sex evolve? A) To increase genetic diversity.
HOW, mechanistically, is sex mediated? A) One animal gets a pointy bit and the other gets an inversely-shaped part. If used properly, these parts result in meiosis occurring.
Clarifying? I suggest thinking of "why" and "how" along the lines of Aristotle's final and efficient causation.
Also, the argument above about denying the metaphysically given is off the mark.
There is an evident distinction between:
1) A selective pressure that did occur historically but that was not a universal necessity of the laws of physics (e.g. the presence of a certain predator on an island)
And
2) A physical fact which life could not have evolved to circumvent, such as f=ma
To bring in the false dichotomy of the necessary and the contingent in philosophy, as though it shows some kind of fallacy in the above distinction, is quite wrong.
There is a limit to how precisely one can use language. It will always be open to semantic misinterpretation by those focused on polemics. |
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| Sunday, June 28, 2009 at 9:26:33 mst
Comment ID: #30
Name: Adam Spong
Also, please don't someone pick on the technical acurracy of my meiosis example. I was speaking loosely.... |
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| Sunday, June 28, 2009 at 9:44:12 mst
Comment ID: #31
Name: Anthony
"There is an evident distinction between:
1) A selective pressure that did occur historically but that was not a universal necessity of the laws of physics (e.g. the presence of a certain predator on an island)
And
2) A physical fact which life could not have evolved to circumvent, such as f=ma"
It is not evident to me. |
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| Sunday, June 28, 2009 at 10:55:32 mst
Comment ID: #32
Name: Adam Spong
I take it that you are trying to claim that the above distinction uses the false idea in philosophy of the "contingent" and therefore misses Ayn Rand's point about causality. Everything is caused and so could not have happened differently.
This is a different context. The point does not apply.
This is a distinction between types of causes:
1) A factor in evolutionary history that biology *could* evolve to prevent (aging), and
2) A factor representing an upper limit imposed by physics (the idea of aging as an *inevitable* consequence of mechanical/chemical forces, or of thermodynamics, etc.)
It's as if you took a survey of evolutionary history up to the point before animals began to breathe air.
If someone came in and said:
"All animals evolved so far to breathe only water, but that is not an absolute unchangeable barrier imposed by the laws of physics, and it is biologically possible for them to evolve to breathe air."
Would you interject and accuse the speaker of failing to understand causality? They evolved to breathe water and it couldn't have happened differently and to suggest that breathing air is possible is to deny that A is A?
No? But that's what I'm saying, with aging in place of breathing water.
I grant you that there are some subtle distinctions to be made here, but it would be really unfortunate if one were to let their understanding of the Objectivist point about causality and "contingency" obscure the importance of the scientfic theory here. |
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| Sunday, June 28, 2009 at 13:00:48 mst
Comment ID: #33
Name: Adam Spong
By the way, thanks for the sci-fi references William, I might have to check those out. |
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