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Govtcheez
08-08-2005, 07:19 AM
I'm afraid I don't have a lot more to add than the question. With new breakthroughs in medicine coming all the time, we're ensuring that more and more people can and will pass on their genes. This effectively ends natural selection for humans, doesn't it?

webmaster
08-08-2005, 07:36 AM
That may be partially true, and it's probably not a bad thing. Of course, if people continue to choose to have children later and later in life, then there will probably still be some selective pressure against genetic diseases that typically take hold in mid-life until we've fixed those problems. The other thing to keep in mind is that there's more to natural selection than physical health. For instance, mental health or mental ability may be harder for medicine to fix and evolutionary pressures may shift to focusing on those skills. It's even imaginable that a new selective pressure could be the ability to be treated--some people may respond better to a wider range of treatments, and could tend to survive longer or at least survive through childhood to the point where they can pass on their genes.

Unfortunately, since evolution's effects take place on a relatively long time-scale, we probably won't be around to find out if or how humans continue to evolve.

Govtcheez
08-08-2005, 07:47 AM
> That may be partially true, and it's probably not a bad thing.

Why? Obviously it's great that medicine has come so far, but why would it be a good thing for the species to stop developing?

> For instance, mental health or mental ability may be harder for medicine to fix and evolutionary pressures may shift to focusing on those skills.

I really don't know much about neurology, but I assume that as we learn more and more about the brain, we can start dealing wiith these problems. I see what you mean, though.

>Unfortunately, since evolution's effects take place on a relatively long time-scale, we probably won't be around to find out if or how humans continue to evolve.

Speak for yourself - I'm going to be frozen in a lab somewhere :cool:

Fordy
08-08-2005, 07:53 AM
Perhaps being able to develop methods to lengthen life can be seen as an evolutionary development, just as crocodiles seem to have developed antibodies that can allow them to lose limbs in filthly water without them catching infections and dying.

SMurf
08-08-2005, 07:56 AM
Speak for yourself - I'm going to be frozen in a lab somewhere :cool:
Tell Walt I said "Hi", and that his company hasn't really moved on from where he left it. ;)

Medicine may well be evolving, but bacteria and virii are too. As they are being destroyed through contact with antibodies, their structure can change over time so they are able to once again attack a previously immune person.

Okay, we won't ever be as vulnerable as we used to be, but there will always be unlucky people and sociopaths who pump themselves full of antibiotics for a cold and help the problem.

GanglyLamb
08-08-2005, 08:19 AM
Apart from diseases, bacteria etc there are still issues like these. (http://news.bbc.co.uk/2/hi/health/4745341.stm)
Research like this can really extend peoples life, without needing to worry about the fact that we will adapt to the drugs and become resistent in some way.

But like SMurf said we and our medicines evolve but nature around us evolves as well, its just a matter of trying to be one step ahead of nature.
And I feel that in that way we "broke" evolution since we/new drugs are the reason new diseases or variants on existing ones come to this world.

But maybe it was all destined to be like this :D... who knows.

Govtcheez
08-08-2005, 08:29 AM
> there are still issues like these.

I don't think anyone will ever be able to explain why Brits insert random "o"s into words.

SMurf
08-08-2005, 08:40 AM
Hey! It's our language, we invented it, so we have to find some way of making it look French against the way you people have phonetically correct spellings!!! :mad:

Brian
08-08-2005, 08:51 AM
Natural selection still occurs. Not so much in dying out as in reproduction. You don't see many cripples and retards getting dates.

Sang-drax
08-08-2005, 09:14 AM
Have human beings "broken" evolution?
[...] With new breakthroughs in medicine coming all the time, we're ensuring that more and more people can and will pass on their genes. This effectively ends natural selection for humans, doesn't it?
Yes, it ends natural selection. But this state has only lasted for less than 100 years and only in a small part of the world. If the majority of the world's population becomes as rich as the richer nations and this state lasts for tens of thousands of years, then and only then will humans have broken evolution.
As it is now, evolution is nowhere near broken.

LuckY
08-08-2005, 09:26 AM
It's funny that you mention this, Government, because I've thought about this many times over the years. In fact, last night I was thinking about a related topic. I was watching DiscoveryHD (yes, I had to mention the HD because I just got it and can't stop creaming over it's splendor) and they were talking about how in the last 50 years we've destroyed more forests than we ever have in the rest of recorded history combined. People argue that we humans are destroying nature. I submit to you that everything we humans are doing to the planet and to each other is natural.

After all, how does one truly define what is natural? I doubt anyone would argue that the lives animals live in any geographical location are not natural because they do anything and everything the extent of their intelligence permits. So when one species of predator begins wiping out a species of it's prey out in the middle of a rainforest, it's simply natural selection taking place. When very early man began figuring out how to make fire and spears to hunt and cook Wooly Mammoths and whatnot that was still natural, right? We even wiped out the species all together, but that was a process of evolution. Now that we have advanced as far as we have, we continue to do everything our intellect permits. Just because we are aware of the effect we're having on the planet and the evolution of all beings, doesn't make it any less natural.

The point I'm getting at is that evolution is thriving strong and hard. As Darwin stated, "Only the strong survive." "Strong" is a relative term, and we are simply relaxing the restrictions on what defines a living being as strong. Lots of defective people still pass on their genes because they are strong enough by the contemporary definition in our society. Well, at least that's how we think in civilized society; things are much different in lesser developed nations.

Govtcheez
08-08-2005, 09:33 AM
> I submit to you that everything we humans are doing to the planet and to each other is natural.

"Natural" implies there is some order to the way things "should" be, and I think that's a fallacy. There is no "should", things just are.

LuckY
08-08-2005, 09:43 AM
"Natural" implies there is some order to the way things "should" be, and I think that's a fallacy. There is no "should", things just are.My sentiments precisely.

no-one
08-08-2005, 10:33 AM
>
"Natural" implies there is some order to the way things "should" be, and I think that's a fallacy. There is no "should", things just are.
<

dude, wow... somebody who actually believes in "darwinian evolution" without saying there's a right and wrong way for things to go?

Govtcheez
08-08-2005, 10:38 AM
This isn't a religious discussion. If you feel like making it one, feel free to make another thread.

Mods, please close this if it goes too far down the "evolution is a lie/no it isn't" path. I meant this a way to discuss how technology affects natural selection in people, not anything else.

no-one
08-08-2005, 10:55 AM
dude what the ........?... did i even REMOTELY imply anything like that? lemmie explain!

i was pointing out how it seems most evolutionist seem to believe there is a right way for it[evolution] to happen? and its actually kinda "refreshing" to see somebody who believes what they call "darwinian evolution", while also believing what you said, there is no technically right way things should be...

hence the point that our technological advancements are 100% in-tune with evolutionary developemnet! being they help us survive and dominate... and should theoretically "improve" our "genetic crop".


seriously... stop being such an ...............

Edit: just because i've argued against it in the past, and dont believe in it... dont mean .........

Govtcheez
08-08-2005, 11:11 AM
Sorry, I took it the wrong way. I meant to put that disclaimer at the top, anyway :)

It's still kind of offtopic, but it's my understanding that the genes that get passed on the most become most common. "The fittest" genes are usually the ones that get passed on, because they're more likely to survive, better suited for the environment, more attractive, etc. That doesn't necessarily mean there's some right way to happen, it's just what happens most frequently.

Again, sorry.

no-one
08-08-2005, 12:30 PM
actually thinking about it, i cant say i blame you... i used to be and still am a bit of a dick...

>
It's still kind of offtopic, but it's my understanding that the genes that get passed on the most become most common. "The fittest" genes are usually the ones that get passed on, because they're more likely to survive, better suited for the environment, more attractive, etc. That doesn't necessarily mean there's some right way to happen, it's just what happens most frequently.
<

ok, to my understanding(which is SMALL) of genetic's its really not a pick of the fittest, there are a LOT of deformities(mutations) that are dominant genes, being things like polydactalism, curly hair(haha), bad eyesight, albinoism.. and other not seeminly bad things including freckles, baldness, hairline... etc... are all dominant genes... being if you only have one gene of that trait... your still screwed... and generally if the parent only has one dominant gene of the pair, then there's a 50/50 chance you get the dominant one...

so... my understanding is "natural" natural selection happens after the semi-"random" genetics... when you die because of your ........ty genes... then leading to the point that we are spoiling our gene pool by keeping the bad genes alive through advanced medicine... ehhhhhh.... this subject is just SCREAMING loooong discussion...

but then again... im talking out of my ass, cause my understanding of it is slim.

edit:... added some ...........

edit: off topic but, this thinking is what spurred people like the NAZI's being they killed people they thought were genetically inferiour... to prevent "soiling" of the gene pool...
edit: or that was their excuse anyway...

elad
08-08-2005, 12:59 PM
I believe this is a delicate balance. Technology has helped more people live longer--better public health measures, better nutrition, better protection from routine dangers due to exposure to predators and risks associated with a variety of environmental risks, treatments for any number of acute/potentially life threatening illnesses, changes in social attitudes, etc. I don't think there is any question that more of us as a total percent of all of us born survive to reproduce than ever in history. This means there are more genes (given a standard rate of mutations arising spontaneously within a given population, and that may not hold true with the thinning of the ozone layer) in a bigger variety than ever to share. However, that also means we are putting more pressure on the systems that support us. Habitat destruction in the tropical rain forests and sub-saharan Africa as well as the awesome potential of nuclear catastrophy clearly demonstrate that we can decrease our numbers as a species by adversely affecting our environment, even if we can "compensate", as a species, for many of these pressures, at the moment.

I think a complementary question to that posed is: are we putting ourselves at significant risk as a population, if not a species, by our activities as a species; (though this topic has been more widely explored in a variety of media than the one posed originally on this thread).

Lurker
08-08-2005, 01:58 PM
I think what'll happen in the future is much more racial blending. Many distinguishing characteristics, especially in the US, will come together. We'll become much more resistant to disease, obviously, and possibly some of our attributes will change due to that. If we survive long enough, a new era of evolution will come along when we live on other planets. 3 generations may even be enough to provide us with a new race (although still very similar to us) if we settle on Mars, and the people there don't leave. It's all speculation, but that's the fun part :p .

dpro
08-08-2005, 05:44 PM
Well there is still some natural selection if you think about it. Was there ebola or AIDS back in the earlier years. I believe firmly that mother nature has built in stopgaps to stop us from completely overpopulating. Eventually we would die out should the populations of everything else disappear. We all depend on the planet for air (from trees/oceans), food (from animals and plants), and of course our rather small source of fresh water on the planet.

I think there are a lot of triggers in the world which start to "flip" should anything get radically out of balance. True we can circumvent some, but there is no known cure for AIDS, ebola, or other diseases which strike. They are there for a reason, to mold and shape populations. That is my own take though.

Personally I find it silly that many people hold on to certain prejudicies without rethinking them every so often. But I am strange that way.

Clyde
08-08-2005, 05:51 PM
I was pointing out how it seems most evolutionist seem to believe there is a right way for it[evolution] to happen?


They don't think that. Most evolutionary biologists think if we could turn back the clock and start life again then fastward organisms of today would look very different the second time round. Now just how different is a very interesting question, unfortunately, rather difficult to answer.

Medicine certainly changes the ball park for evolution, i wouldn't say it has stopped it, medicine is not perfect (nor will it be for the forseeable future) further reproductive fitness is more than being kept alive, so i think that there is currently and will remain a selective pressure on homo sapiens. However evolution still seems to me essentialy redundent in our case because we are changing our lives through technology far far FAR faster than anything evolution can ever do.

As to why Darwinian selection might be viewed as "bad" well for a start its amoral as a process, its blind to suffering and pain, a millimeter of adaptation is bought at the expensive of a billion lives. "Nature is red in tooth and claw" etc etc.

Additionally adaptation does not equal improvement or advancement, atleast not in the way we usually use those words, it simply means more likely to pass on ones genes, so evolution ceasing to be much of a factor is not necessarily a bad thing even disregarding the ethics of the process, evolution could _in princple_ lead us towards a future humanity who's characteristics we might view as unfavourable (for example making us more violent and antisocial).

BobMcGee123
08-08-2005, 06:17 PM
I'm afraid I don't have a lot more to add than the question. With new breakthroughs in medicine coming all the time, we're ensuring that more and more people can and will pass on their genes. This effectively ends natural selection for humans, doesn't it?


I see an evolved species as one that is most likely to survive, and when a species has a very high survival rate it introduces all kinds of different genetics, increasing the chances of survival against a wider spectrum of antagonists...therefore I see evolution as speeding up instead of slowing down (for the humans*).




*Yes, for the humans, those crazy mother ........ers.

But ultimately evolution is one of those silly ideas invented by a group of elitist Liberals that hate America (they also tried to convince us that we went to the moon)...crazy mother ........ers!

Zach L.
08-08-2005, 06:35 PM
Clyde! You're still around!


At the risk of restating what others appear to have already said (if I interpret them correctly), so long as there is an environment, we will continue to adapt to it. I can forsee the rate of genetic drift slowing (perhaps significantly), but even as we alter our environment to suit us, we are not doing so at the exclusion of other "forms" (for lack of a better term) of humans that are equally suited to the environment we have created as we are now (of course, I am refering to changes significantly different from current differences amidst the population).

novacain
08-09-2005, 01:05 AM
>>However evolution still seems to me essentialy redundent in our case because we are changing our lives through technology far far FAR faster than anything evolution can ever do.

I think that evolution is alive and well.

Now the major force in evolution is technology, will it force us to adapt to other planets?


Say I genetically engineer a new version of humans that is 'stronger' or 'fitter', from a Darwinian evolution point of view.

Is my new human contributing to evolution or not?

I think it would be as it is a result of a humans interaction with their environment.

Clyde
08-09-2005, 06:27 AM
Say I genetically engineer a new version of humans that is 'stronger' or 'fitter', from a Darwinian evolution point of view.

Is my new human contributing to evolution or not?


Well, i'm not entirely convinced you can call that evolution, not in the Darwinian sense. Darwinian evolution normally refers to the proces of mutation and selection, leading to a gradual change in phenotype. That process takes vast quantities of time which is why i see it as fairly irrelevent given technological and corresponding social changes occur on the scale of decades not millenia.

You're example of genetic engineering whilst a reasonable scenario does not, I think, equate to "evolution" in the darwinian sense.

Several reasons come to mind:

1 The change in genotype is not due to mutation.

2 The resulting change in phenotype will be geared towards what we see as desireable, the general "desire" to change ourselves through genetic modifcation could be viewed in a very similar way to the "selective pressure" of Darwinian evolution, however it is not the same. Darwinian selective pressure is SOLEY aimed at increasing reproductive fitness, whereas what people might like to do to their own/their offsprings genotype is bound by nothing more than human whim (though the two may well coincide they are not constrained to).

3 There is a large amount of feedback in the system, because we are doing the genetic modication (vs. random mutation) the entire process becomes highly self reffering, the genes we choose for our offspring will effect (in a non-trivial way) the genes they choose for their offspring. In biological evolution this is not the case, broadly speaking the process of mutation is fixed.



Clyde! You're still around!


Hello :).

nvoigt
08-09-2005, 09:15 AM
If you make it idiot proof, the universe will create a better idiot.

We will never be completely immune to diseases. We will never be immune to overpopulation and resulting disasters. We will never be immune to greed and resulting conflicts.

We will never break evolution, we are part of it. There is nothing that would stop evolution. If we could stop it, stopping it would be an evolution in itself and surely not the last one.

novacain
08-09-2005, 06:31 PM
If a genetically engineered plant 'escapes' and becomes, through 'normal' natural selection, the dominant variant of its species, is that evolution?


>>That process takes vast quantities of time which is why i see it as fairly irrelevent given technological and corresponding social changes occur on the scale of decades not millenia.

The 'Culex molestus' form of mosquito found in the London Underground railway system took a lot less time to evolve, only a hundred years or so. Its evolution was driven by the available diet and the conditions (chemicals ect).


Though this is a long time for an insect...

Zach L.
08-09-2005, 07:22 PM
>> Though this is a long time for an insect... <<
Correct. It is more to do with generations of a given animal.

From this (http://www.mosquito-zapper.com/facts.htm) site, it states that a female mosquito generally lives 3-100 days, and a male 10-20 days. (I don't know the specifics of the species you mentioned.) Doing some rough calculations from the numbers on the website, 100 years is going to be something like 1500+ generations... which is fairly significant.

As to the escaped plant. No, it would not be evolution, it would, however, be natural selection. It's equivalent to species of plants/animals being introduced to an area that it is non-native to, and either eliminating or assimilating (depending on the details) a competing native species.

Epo
08-09-2005, 09:09 PM
I think that evolution and natural selection are linked. (Should natural selection be broken, so is evolution).

I believe we've broken natural selection. Imagine how tough our species would be if hospitals didn't exist. (Or we'd be extinct).

Hoping extinction wouldn't set in: survival of the fittest/smartest would. If somebody falls off a ladder because they didn't secure it properly, well, it would be a lesson for everyone else and we'd get smarter/learn how to do things properly. The strong would pick on the weak, and slowly the weak would die off. Too generous? Well the greedy people will eventually take everything you own, and you will die off. I know it's sensitive to some people, so I'll only mention it quickly, but should someone suffer from mental health problems, they would die off too.

What you'll have left is the smart and strong leading the smart and strong. There's your natural selection (or one path of it anyways; read my note at the bottom).

However, we have hospitals, medications, urgent care clinics, etc. to care for the weaker and dumber members of our species (along with our emotions such as compassion, generosity, and other bonds). And so, they stick around a lot longer than they "should" (with reference to natural selection).

NOTE: Their are numerous paths this can branch off into. A really smart person could develop something to render strength useless (I.e. a fantastic impenetrable bubble). Or, physical strength could be the mere deciding factor. But I've chosen a mix of the two, equally developed (because without intelligence, it doesn't matter if you can lift a house, and without physical strength, it doesn't matter how smart you are if you can't lift your ray gun). As I said, this is just one path.

Now, evolution has to do with how the different mutations of genes conquer eachother (I don't think a natural/man-induced change is relevant here...). If there are two people, all other things equal, and one has the "smart" gene, while the other has a "dumb" gene, well, evolution will be when the smart gene continues to live while the dumb gene dies off.

But it's more complicated than that since "all other things" are never equal. One person may be smarter with straight hair, but the other may be more able-bodied with curly hair. Who's to say which gene (intelligence, strength, or hair) is responsible when one of those people die and another continues living? (Not to mention the environment in which they live).

You'd have to re-create the same scenario and test it thousands of times. But no two people are completely alike, so each time the results are a bit skewed. And, to add to this, should curly haired people be the "weak" link, it's not very apparent, because we reproduce them fast enough that we never really see the shortage. And since we reproduce the flaws, we've halted evolution as well. Natural selection can't do its thing, so those flawed genes will hang around.

So, with the halt of natural selection due to hospitals (increasing life expectancy past what it naturally should be), and the reproduction of flaws, we've also halted evolution.

Should only people with genes that improve "life expectancy" (again, referring to natural selection standards) mate, excluding all others, without compassion to help them, then I'd say evolution would be back on track. But, that's not the case.

It's a bit of a read, and I've got a lot more to say, so I've tried to throw out the key points I've got and hope you can fill in the blanks/give it a thought. And of course, this is only one way to look at it.

Clyde
08-10-2005, 06:24 AM
I believe we've broken natural selection. Imagine how tough our species would be if hospitals didn't exist. (Or we'd be extinct).


The species would not really be much "tougher" if modern medicine had never been developed (well perhaps there might be less allergies but that's not due to evolution).

Modern medicine is relatively new and bacteria and viruses evolve far far faster than we do anyway.

You could probably make the case that without modern medicine conditions like sickle cell anaemia or cystic fibrosis would be rarer in the developed world. (But then what exactly does the "developed world" mean if we are disregarding modern medicine).

Most mental health problems would be completely immune to evolution because they kick in long after individuals reach reproductive age. (and if there were no medicine no one would live that long anyway).



However, we have hospitals, medications, urgent care clinics, etc. to care for the weaker and dumber members of our species (along with our emotions such as compassion, generosity, and other bonds).


Hospitals reduce the selective pressure against genes that increase the probability of contracting a condition that is treatable, they do not remove that pressure unless modern medicine has reached the point where that condition does not constitute a disadvantage _at all_.



survival of the fittest/smartest would


Fittest is only fit in the context of reproductive fitness, that's all evolution "cares" about, if being thick but strong makes you more likely to reproduce then that's what evolution will favour.


Hospitals have not stopped selection, people still die before they reach reproductive age. Further selection is not limited to death, selection is based on reproductive fitness, obviously dead people can't reproduce but two live people are not necessarily equal.



So, with the halt of natural selection due to hospitals (increasing life expectancy past what it naturally should be), and the reproduction of flaws, we've also halted evolution.


The phrase "increasing life expectancy past what it should naturally be" has no meaning.

We haven't halted evolution, we've altered it perhaps but the real reason why evolution is fairly irrelevent for our future development is because technology has rendered it redundant: technological development is orders of magnitude faster than evolutionary change.