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#21 Delvo

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Posted 07 April 2003 - 01:50 AM

JadziaDax, on Apr 6 2003, 02:28 PM, said:

So what's my take on genetic modification? Only do get rid of things like NF or other genetic disorders.
I'm pretty sure almost everyone would be happy to see genetic engineering solve problems like yours. But the problem, if one wants to draw a line between that and other kinds of genetic engineering, is where to draw the line. I think as soon as a standard is established that genetic engineering is OK for fixing disorders, lots of things will suddenly become bogusly recognized as disorders.

And that doesn't even consider the fact that some people will presumably cross the lines anyway...

I can only see genetic engineering, if it ever gets to the point of being able to pick and choose traits, as unhealthy for society. It'll be another way for life to favor the rich and be unfair to the poor, unless some kind of government program is instituted to make such therapies available to everyone, in which case it'll just be another way for the rich to get punished for being rich by having their money confiscated and spent on people who didn't earn it but will feel entitled to it. And then what will we get? A population consisting almost entirely of people with what-would-once-have-been-outstanding athletic and mental abilities, but STILL a limited number of avenues for such people to make much of themselves, while the mundane jobs will still have to be done and everyone will have too much potential to be satisfied settling for them. The solution? Engineer some of them, maybe even most, to be weak, dumb, and happy not to have all the stresses and responsibilities that the "upward" modified ones have!

Prejudices in both directions will dominate culture's every little nook and cranny during these changes, with the "advantage" ultimately swinging from the normals at the start to the modifieds later on.

So now we've gone from Gattaca straight to Brave New World. Neither is a very cheerful vision of the future, nor are any intermediate stages I can realisticly foresee. I'm just glad I'll be dead before it happens and won't be having any kids to put through a world like that.

BTW, it will be worse for men than for women, not only because men are both internally and externally driven more to competition (which most of them will be set up from the start to lose), but also because after the science is sufficiently mastered, every baby girl born will be engineered to look just like her mother always wanted to, so all women will look exactly alike. Yet another reason I don't want to live in THAT world.

#22 Techfreak Ziana

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Posted 07 April 2003 - 02:28 AM

A few thoughts...

Nikcara, on Apr 6 2003, 12:56 PM, said:

It seems likely that greying and baldness stayed in the gene pool because it didn't have a deterimental effect, rather then because it had a helpful one.  If it had a good side effect, I think that everyone would be going bald and grey at some point because its a trait we've had a good long while - probably long enough to have weeded out people who didn't go grey/bald.
~nod~ Another thing to consider is that since during the vast majority of the time in which we were doing this evolving, few people lived long enough for these traits (greying/balding) to become apparent, it might have just happened to be there and not really get 'noticed' in the evolutionary process. Both due to the rarity of it being evident at all, and that once it did become evident those individuals were generally (not in modern times, of course) too old to reproduce, once it was evident that a person had those characteristics it was too late for selection to do much about it.

Christopher, on Apr 6 2003, 04:10 PM, said:

I couldn't think of a good reason why baldness would be adaptive, anyway.  I'm still not so sure about greying, though -- by analogy with our very close relatives, the gorillas.  Male gorillas' back fur goes from brown or black to silver upon maturity.  For them a change in hair color is a genetically programmed signal of a life-cycle transition; so it seems reasonable that it would be for us as well.
Yeah, but with the gorillas (afaik) they do that at about the same time (being an indicator of life cycle stage and all that...); with humans, greying happens at widely varying times.

As for balding, that's a 'side effect' of testosterone, iirc; the effects of testosterone earlier in life (bigger muscles, deeper voice, etc) ended up being more evolutionarily beneficial than the balding later (which, as I said above, I suspect wasn't taken into evolutionary consideration since most people didn't live that long).
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#23 Techfreak Ziana

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Posted 07 April 2003 - 02:30 AM

JadziaDax, on Apr 6 2003, 02:28 PM, said:

I come at this from a rather unique POV.

I have a genetic disorder called Neurofibromatosis (for more info go to http://www.nf.org look under NF1)

I have it since I was born, I was diagnosed the earliest they could (6 months I think).

Honestly, it's a pain in the butt, most of the time I'm in pain from something that's NF releated. It makes it harder for me to devlop muscle tone, and it will kill me some day because of a inorperable plexiform that's around my windpipe. Since it's slowly started to grow again, it means that some day it will suffocate me.
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:blink:  Ouch  :(

I hope that gets figured out soon, then!
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#24 Techfreak Ziana

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Posted 07 April 2003 - 02:48 AM

Delvo, on Apr 6 2003, 04:39 PM, said:

But the problem, if one wants to draw a line between that and other kinds of genetic engineering, is where to draw the line. I think as soon as a standard is established that genetic engineering is OK for fixing disorders, lots of things will suddenly become bogusly recognized as disorders.

And that doesn't even consider the fact that some people will presumably cross the lines anyway...
Ah, but any lines are arbitrary. To set a line you have to decide "this is as [insert descriptor here] as people are supposed to be", so that anything past that point can be called 'over the line', but once you start saying "supposed..." you introduce arbitrary opinions. Some opinions on that point's location might currently be more prevalent than others, but opinions change, and just because one is more prevalent wouldn't necessarily mean it's "right" (if any of them are).

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I can only see genetic engineering, if it ever gets to the point of being able to pick and choose traits, as unhealthy for society. It'll be another way for life to favor the rich and be unfair to the poor, unless some kind of government program is instituted to make such therapies available to everyone, in which case it'll just be another way for the rich to get punished for being rich by having their money confiscated and spent on people who didn't earn it but will feel entitled to it.
...

It doesn't have to be like that, though. Think about, for example, immunizations at birth and laser eye surgery. The former is now available to almost everyone in 'developed' nations, and a number of companies are donating immunization supplies for the 'less-developed' nations. Through immunizations spreading from being a rare and most likely costly thing at first, a number of diseases which used to devastate young children have been eradicated or greatly reduced. The latter is not to that level of availability yet, but it is in the process of working its way down. Used to be ridiculously expensive (and risky), and now it's much less expensive (can't say cheap yet) and has better results.

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So now we've gone from Gattaca straight to Brave New World. Neither is a very cheerful vision of the future, nor are any intermediate stages I can realisticly foresee. I'm just glad I'll be dead before it happens and won't be having any kids to put through a world like that.
...
Oy...  :eh: There are plenty of positive possibilities, you just have to be open to the idea :)

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after the science is sufficiently mastered, every baby girl born will be engineered to look just like her mother always wanted to, so all women will look exactly alike. Yet another reason I don't want to live in THAT world.

That assumes that everyone's concept of 'ideal beauty' is identical, though. Some concepts may be more heavily promoted in mass-media, but that identical-ness of views is far from the case, and will remain so barring a lot more than genetic engineering ;) :)
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#25 Christopher

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Posted 07 April 2003 - 06:45 AM

Delvo, on Apr 6 2003, 05:39 PM, said:

It'll be another way for life to favor the rich and be unfair to the poor, unless some kind of government program is instituted to make such therapies available to everyone, in which case it'll just be another way for the rich to get punished for being rich by having their money confiscated and spent on people who didn't earn it but will feel entitled to it.
Well, then maybe what's needed is for society to move beyond that way of looking at things.  In many Native American societies, IIRC, it's customary for those who have wealth to periodically give it away, redistribute it through the community.  It's not perceived as "punishment," but as a responsibility to the community which everyone shares.  You do it for others so that they'll do it for you when you need it.  Our culture's attitudes toward property and wealth aren't built into our genes ;) , so they can be changed.

And Ziana put it well -- the relationship between haves and have-nots isn't always as purely adversarial as you assume.  Some people are able to look beyond pure self-interest and use their resources for the greater good, recognizing that what's good for others is ultimately good for themselves.

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And then what will we get? A population consisting almost entirely of people with what-would-once-have-been-outstanding athletic and mental abilities, but STILL a limited number of avenues for such people to make much of themselves, while the mundane jobs will still have to be done and everyone will have too much potential to be satisfied settling for them. The solution? Engineer some of them, maybe even most, to be weak, dumb, and happy not to have all the stresses and responsibilities that the "upward" modified ones have!

Okay, now there's a worst-case scenario.  Such things would probably be prevented by laws.  Our culture is already quite wary of gene modification to a Luddite degree.  Probably it will become more accepted once the vast benefits become clear, but those ethical qualms will remain -- the kind of wide-open extreme you postulate is never likely to happen (except maybe in some dictatorial state that decides to engineer a permanent underclass).

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BTW, it will be worse for men than for women, not only because men are both internally and externally driven more to competition (which most of them will be set up from the start to lose), but also because after the science is sufficiently mastered, every baby girl born will be engineered to look just like her mother always wanted to, so all women will look exactly alike. Yet another reason I don't want to live in THAT world.

Humans are far from uniform in their values, so there's no way every set of parents would share an equal willingness to have their children engineered, let alone have identical standards of beauty.

In fact, I suspect that if engineering the appearance did become commonplace, people would probably seek more diversity of appearance, not less.  It would be a way to show off and exercise the power, to explore its range.  You know, like searching for a unique hairstyle or a distinctive dress.  There would probably be fads, a certain convergence of preferences at a certain time, but all fashions are ephemeral, and standards of beauty no less so than any other.  Maybe you could estimate what year someone was born in by what features they have, but the styles would undoubtedly change from year to year.  That is, if it ever became that casual and universal, which I doubt it will.
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#26 Kevin Street

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Posted 07 April 2003 - 11:04 AM

Here's an interesting sidebar for the conversation:

GM-mosquitoes halt malaria transmission

What if a simple genetic alteration to the mosquito species could totally wipe out malaria, saving the lives of one to three million people every year and ridding the Third World of a major scourge - would the benefits outweigh the risks? Should anyone be trusted with the responsibility of forever changing the genetic code of a "natural" species, or is that a line no one should cross? If it's worthwhile, should we stop with mosquitoes, or go on to remake the world around us at a genetic level?
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#27 Tarandus

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Posted 07 April 2003 - 12:43 PM

Okay, so I just quickly skimmed through the discussion here, so forgive me if I repeat something that has already been said.

Just wanted to add a few notes on why do we have "bad" genes, i.e. why have they not been deleted by selection.

One important reason is that selection works in the present conditions of an organism, but our genes is the result of past conditions. Several of the diseases that are common in the western society is caused by a "too good" life. Our life style has changed radically if we compare with that of our stone age ancestor who's genes in much we have. We have a higher intake of calories, a different composition of food and we exercise in many cases less. Genes that were selected for survival on a low calory diet, and periods of starvation, may have been good 10 000 years ago, but can be causing an increased risk of cardiac diseases today. Another example would be fair skin which is definietly a disadvantage at the equator (skin cancer) but could be an advantage in the north (less light, better uptake by fair skin).

Another reason can be, as someone mentioned, that because we have a longer average life span today, traits that affect us at older age are more frequently displayed. True, there are a lot of people that live longer than the average age, but the average reproductive age is rarely that much higher than the age of first reproduction. And you can't select for things that happens after you reproduce. IIRC Huntington's disease manifests in the 40ies, well after people have reproduced, and is therefor not selected against.

Then we have, again as someone mentioned, that a detrimantal gene can bring advantage in some other situation, e.g. sickle cell anemia, which in heterozygous form gives resistance to malaria. If you compare the frequency of the sickle cell allele in african and american blacks, the frequency has gone down in afro-americans as there is no longer any selection for malaria resistance. Another example I have heard is cystic fibrosis which has been suggested to give resistance to some disease, I don't remember which, in heterozygoes form.

A "bad" gene can also be taken to higher frequencies if it is closely linked to a "good" gene (aka hitch-hiking). I can't really think of any example in humans from the top of my head, but I'm sure they exist.

And lastly we have chance. (Or bad luck if you prefer it.) Bad genes can just happen to be passed on, and even fixed in a population in spite of them being bad. So gene frequencies can change even without selection, just by chance, a process called drift.

Hm, I'm losing my trail of thought here, too many people interrupting...

Oh, yes. Why baldness? One reason not mentioned could be that women have thought it manly and sexy, and bald men would have a better reproductive success, i.e. sexual selection like in the peacock.

And another thing that came to my mind when I was thinking of more "cosmetic" genetic engineering. While some would certainly want to do them, there is will probably also be those who pride themselves in being unaltered. Sort of "I am this good even without being modified."
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#28 Christopher

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Posted 07 April 2003 - 04:54 PM

Kevin Street, on Apr 7 2003, 02:53 AM, said:

Should anyone be trusted with the responsibility of forever changing the genetic code of a "natural" species, or is that a line no one should cross?
We've changed the genetic codes of thousands of species.  It's called domestication.  The only difference is the technique, and the degree of understanding and precision behind it.

And domestication carries its own risks.  Most of our staple foods have had their genetic diversity so drastically reduced by selective breeding and artificial cultivation that entire species could be wiped out by a single blight.  Literally every banana we've ever eaten has been a clone (in the literal sense of a grafted plant cutting) of the same parent plant, genetically identical to every other banana.  That puts bananas in grave danger of extinction.  And they're just one example.  Wheat and corn are similarly lacking in biodiversity, because humans made them that way.  It creates a huge risk of devastating famines within our lifetimes.

We've been engaged in genetic engineering since the dawn of civilization; we've just done it in a more haphazard and uninformed way in the past.  Today, genetic modification may be the only way to correct the damage of our past efforts, and restore the biodiversity of threatened staple crops before it's too late.
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#29 Tarandus

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Posted 07 April 2003 - 05:54 PM

Another thing you can breed using common selection. :(
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#30 Kevin Street

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Posted 07 April 2003 - 08:16 PM

:crazy: That is one ugly cow.

Christopher, your point about the dangers of monoculture is well made, and I agree with you. Genetic engineering is an invaluable tool in the ongoing quest to produce stronger, more diverse and disease resistant foodstuffs - and, imo, its use for such purposes should be encouraged, not discouraged and banned, as so many European countries and protest groups are inclined to do.

But the mosquito example points out another possibility for genetic engineering, another level of human control that would allow us to shape the natural environment as we see fit, altering or destroying species that harm us and encouraging the spread of beneficial species. These animals and plants wouldn't be domesticated in the true sense of the word, but would be real wild creatures, albeit ones of human design.

I'm not sure what to think of this. On one hand, the re-engineering of nature could have very positive effects (saving all those malaria victims, for example) - but on the other hand, I wonder how safe or effective this kind of genetic modification would be once it gets out in the wild, since this sort of thing cannot be undone. (Unlike domestic species or laboratory experiments.) If we start introducing our own mutations into the DNA of other species on a massive scale, we may (or may not) like the results, but we'd have to live with them.
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#31 Christopher

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Posted 07 April 2003 - 09:00 PM

Kevin Street, on Apr 7 2003, 12:05 PM, said:

I'm not sure what to think of this. On one hand, the re-engineering of nature could have very positive effects (saving all those malaria victims, for example) - but on the other hand, I wonder how safe or effective this kind of genetic modification would be once it gets out in the wild, since this sort of thing cannot be undone. (Unlike domestic species or laboratory experiments.) If we start introducing our own mutations into the DNA of other species on a massive scale, we may (or may not) like the results, but we'd have to live with them.
Well, it would hardly be the first time that human technology has had unintended consequences on the wild.  Pollution, climate change, ecosystem disruption due to the transplantation of species between regions.  When humans began hunting with dogs and spears, we contributed to the extinction of whole species.  When we migrated to the Americas in the same era, we vastly transformed their whole ecology.  The herding of ruminants stripped vast areas bare of vegetation and created deserts like the Sahara.  The Columbian Exchange following 1500, the extensive transplantation of plant and animal species between the Old World and New, led to radical transformations in ecosystems across the globe.  Our extensive construction of dams over the last century has not only radically altered water flow patterns worldwide, the sheer mass redistribution has slightly shifted the rotational axis of the planet.  It's a total myth that the potential to alter the whole world is something new.  We've done it many times.

You can't separate the human sphere of influence from the "natural" world.  We're a part of nature, our technology is a part of us, and like every other part of nature we interact with our environment, affecting it as it affects us.  That environment has no "pristine" state, but is always in flux.  So instead of asking whether we should risk doing things that affect the larger world, when we've always done so and can't help it, we should be asking how we will choose to affect it.  I for one would prefer that we have more knowledge and technology so we can improve our control over the effect we have on the world.  Yes, there's still a risk of unintended consequences, but the greater understanding we have now means that the risk is much less and much easier to manage than it was in the past.
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#32 tennyson

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Posted 07 April 2003 - 11:08 PM

The Cystic fibrosis gene provides resistance to Cholera.
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#33 Techfreak Ziana

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Posted 08 April 2003 - 02:42 AM

Kevin Street, on Apr 7 2003, 12:05 PM, said:

:crazy: That is one ugly cow.
Its... rear... looks like... a giant pumpkin...

:suspect:  :blink:
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#34 Tarandus

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Posted 08 April 2003 - 11:39 AM

tennyson, on Apr 7 2003, 07:57 PM, said:

The Cystic fibrosis gene provides resistance to Cholera.
Thank You! I knew it was something. :)
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#35 Broph

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Posted 14 April 2003 - 12:23 AM

Christopher, on Mar 31 2003, 12:46 PM, said:

Also, most animals don't outwardly display advancing age -- because that advertises weakness to predators and makes you a target.  So again, the fact that we do display age so overtly must have some purpose.
I've been thinking about this one a bit. I wonder if the answer isn't a bit simpler, though. Most animals don't live as long as humans - perhaps that's the reason that they don't show advancing age. I mean this in 2 ways:

1) As you mentioned "outwardly display advancing age" - although there aren't always outward signs, no animal can help but have inside displays of advancing age. When you lose half a step compared to the rest of the pack, you're the one that's trailing and you're the one that's going to be taken down/eaten (the devil take the hindmost, so to say). I would have to say that in the wild, there probably aren't a large percentage of animals who die a "natural" death - so we don't really see how some of them look, other than in captivity, or in the case of domesticated animals. I've seen a number of dogs and cats who have extreme displays of advancing age (loss of hair, trembling, poor stature), etc. And in the wild, those animals with few predators are the ones that we generally see as having advanced age.

2) Aging is a factor of time. As I said, most animals don't live as long as humans. A display of aging, by definition, takes time to appear. Because animals don't live as long as humans (and because of other factors, such as skin being covered by fur), they simply don't have the opportunity to have those conditions that make aging appear (which is why less aging might comparatively show on a small animal with a high heartrate/metabolism, etc.). One of the things that causes aging in people is the replication of DNA through messenger RNA. Througout or lives, our original DNA is copied and created and copied and repeated. Over time, these "copies" become a little less true ("replicative fade" in the cloning episode of TNG isn't that far off the idea). Additionally, a creature that lives as long as we do has things like deposits and buildups in the arteries - an animal that doesn't live as long (and that probably eats a better diet), wouldn't have the opportunity to have such deposits develop over time.

So I wouldn't say that displays of aging are built into our genes as much as there are other factors that cause those displays. I would, however, agree with you on the male pattern baldness idea - though according to genetics, I'm supposed to be bald by now. Go figure!

#36 Christopher

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Posted 14 April 2003 - 02:06 AM

Broph, on Apr 13 2003, 04:12 PM, said:

1) As you mentioned "outwardly display advancing age" - although there aren't always outward signs, no animal can help but have inside displays of advancing age. When you lose half a step compared to the rest of the pack, you're the one that's trailing and you're the one that's going to be taken down/eaten (the devil take the hindmost, so to say). I would have to say that in the wild, there probably aren't a large percentage of animals who die a "natural" death - so we don't really see how some of them look, other than in captivity, or in the case of domesticated animals. I've seen a number of dogs and cats who have extreme displays of advancing age (loss of hair, trembling, poor stature), etc. And in the wild, those animals with few predators are the ones that we generally see as having advanced age.
To some extent, this is no doubt true, but it's also true that domesticated animals, who usually live far longer than animals in the wild, usually do not show such overt signs even at a stage in life corresponding to extreme age in humans.  If a 34-year-old cat corresponds to a 150-year-old human, then my cat Spooky, who lived to be 16, would've been the equivalent of 70 or more, and his coat at the end of his life was as full and lustrously black as it was when he was a kitten (aside from that tiny little spot of white in the middle chest that male cats often seem to develop after a few years, at least in my experience).  Certainly he showed signs of weakness and deterioration, but not the overt surface signs I'm specifically talking about, extensive baldness and loss of hair pigment.

Another problem with the "not living long enough for it to show" argument is that baldness and white hair can show up in very young humans.  When I went to my 10-year highschool reunion, it was startling how many of the men there (all around age 28) were bald.  Heck, I think Patrick Stewart was bald by 20.

So clearly humans are more disposed to baldness and pigment loss than most other species.  The arguments presented here have made me much more skeptical of my hypothesis that they serve a specific genetic purpose in us (or at least that baldness does), but there is undoubtedly a difference.

Although I suppose it could be a matter of proportion.  I talked about the difference between "cat years" and "human years," but maybe that's inapplicable to this question -- maybe the decay processes don't develop in proportion to a species' typical lifespan, but are purely a function of how much real time has elapsed.  Naturally a species that lives longer will be subject to more wear and tear on its cells and tissues.  Maybe if cats lived to be 60 they'd go grey and bald too.  Though the young-baldness issue I cited above works agains this argument too.  And there are animals that, all else being equal, tend to live longer than humans, like elephants, crocodiles and tortoises.  Of course, they have little or no hair, and elephants have wrinkly skin to begin with, so there aren't many grounds for comparison. ;)
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#37 Broph

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Posted 14 April 2003 - 03:11 PM

Christopher, on Apr 13 2003, 10:55 PM, said:

To some extent, this is no doubt true, but it's also true that domesticated animals, who usually live far longer than animals in the wild, usually do not show such overt signs even at a stage in life corresponding to extreme age in humans.
Well, some domesticated animals. I've seen many dogs that have shown signs of advanced age, as I've mentioned before. I've seen fewer cats that show signs, but there have been a couple, including "Midnight", a cat that was basically a sack of bones when she passed. But certainly there are other domesticated animals - farm animals like horses, cows, goats, sheep, etc., certainly show their age.

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Certainly he showed signs of weakness and deterioration, but not the overt surface signs I'm specifically talking about, extensive baldness and loss of hair pigment.

Mmmm - but remember - it's not hair - it's fur. Maybe there's just something about fur that keeps it from losing pigment. Maybe it's the fact that animals like that shed - their ability to grow new fur may be what keeps it from turning white or grey.

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Another problem with the "not living long enough for it to show" argument is that baldness and white hair can show up in very young humans.

But I agreed with you regarding baldness (at least male pattern baldness) being genetic.

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The arguments presented here have made me much more skeptical of my hypothesis that they serve a specific genetic purpose in us (or at least that baldness does), but there is undoubtedly a difference.

Agreed - I don't think that there is a purpose, but I do think that it's something that just happens with time.

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Naturally a species that lives longer will be subject to more wear and tear on its cells and tissues. 

That's all I'm saying. I have a friend who used to work in a lab where they did experimentation on mice - they use mice because there are certain similarities to humans, but they can see quicker what the effects, and to an extent "long-term" effects might happen, than they would in human trials.

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Maybe if cats lived to be 60 they'd go grey and bald too.  Though the young-baldness issue I cited above works agains this argument too.

Well, maybe animals that had a tendency towards baldness either had other traits that allowed them to die out, or females found the males to be unsuitable mates, so the genes died out. Humans are able to control their environment and were able to keep what other species may see as an undesirable trait.


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