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Author Topic:   Humans are losing.
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 4 of 58 (308327)
05-01-2006 9:20 PM
Reply to: Message 1 by Douglass
05-01-2006 7:01 PM


Basically, diseases are evolving and we're not.
What makes you think that's the case? In some studies, immunological histocompatibility turns out to be an enormous factor in human sexual attraction and mating.
We're still evolving, and our historical exposure to diseases like smallpox and bubonic plague give us resistance to new diseases, too. Plus, we have the advantage of actually being able to predict disease behavior. The best a disease can do is mutate randomly.

This message is a reply to:
 Message 1 by Douglass, posted 05-01-2006 7:01 PM Douglass has not replied

Replies to this message:
 Message 5 by Darkmatic, posted 05-02-2006 9:47 PM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 10 of 58 (308666)
05-03-2006 12:35 AM
Reply to: Message 5 by Darkmatic
05-02-2006 9:47 PM


The problem is , survival of the fittest isn't a factor anymore in humans today .
If you can read this, no, "survival of the fittest" probably isn't an issue where you live. Where you live, where you get enough to eat and you have shelter from the elements and reliably clean water and medical attention on demand, yeah, you'd probably expect to see all manner of unfit people walking around and, like, survivng everywhere.
Is it really so hard for you to concieve of the fact that the life I just described above does not represent reality for the majority of human beings? The top 5 killers of human beings aren't cancer and AIDS; at least three of them are conditions that you could simply treat by feeding people enough to eat and letting them drink clean water. I'm sorry if I sound crass, but literally every time a thread about human evolution is opened, within the first 10 posts someone feels the need to make the claim that you just made - that human evolution is at a standstill because we've put an end to "survival of the fittest." But simply turn on the news and see the situation in Darfur and you'll quickly learn how unsupportable an idea that is.
I mean, seriously. Whatever gave you the idea that humans had suddenly advanced beyond the reach of death and disease? Sure, you and I living in America can be treated for a wide variety of formerly-fatal conditions, but there are still genetic diseases that will knock you out long before you've had a chance to pass that gene onto your children. Even in America.
so basically natural selection has been done away with .
I wish I lived in your fantasy world. I truly do. But even if we did - it's called "sexual selection." It's a fact that human beings don't mate at random, but under the influence of instinctual reactions that help us recognize mates with good genes. Even if fatal selection weren't an issue, human beings would still not mate at random and thus, sexual selection would still constitute an evolutionary force on our genes.
I have to know - who told you that natural selection wasn't operating on humans? Seriously?

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crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 11 of 58 (308667)
05-03-2006 12:43 AM
Reply to: Message 8 by EZscience
05-02-2006 10:43 PM


We are severely suppressing selection on the human gene pool by enhancing everyone's reproductive success.
Um, Western countries have the lowest birth rates in the world. In what sense is our reproductive success being "enhanced?"
Look, turn on the news and it's easy to see what the selective forces on human evolution are right now:
1) Not being born in a Western country.
2) Anything that helps you survive malnutrition, disease, and drought in a hot climate.
If you want to address human evolution, you have to start with the reality of what fitness means in an evolutionary context and apply the same rules to humanity as you would to any other population - not the loaded Anglocentric concepts that arbitrarily favor Western civilizations as being objectively "better". Hey, I love living in the West. It's great to have enough to eat and clean water and a hospital across the street.
But my wife is on birth control, and I'm nearly 30 years old with no children. If there's any selection going on, it's selecting against people like me. From an evolutionary perspective, we're failures, likely doomed to extinction. Certainly not the pinnacle of human evolution.

This message is a reply to:
 Message 8 by EZscience, posted 05-02-2006 10:43 PM EZscience has replied

Replies to this message:
 Message 13 by EZscience, posted 05-03-2006 11:08 AM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 14 of 58 (308749)
05-03-2006 11:40 AM
Reply to: Message 13 by EZscience
05-03-2006 11:08 AM


I was thinking more along the lines of medical interventions that enhance survival of premature babies and other individuals bearing faulty genetics that otherwise would not live to reproductive age.
I don't know anything about obstetrics. Is premature birth a genetically-influenced condition? Or does it tend to occur at random?
Like I said before there's still plenty of genetic conditions that will kill you long before you'd have been able to have children. In fact there aren't all that many we've actually conquered.
These are true for developing countries, but are these really going to be the genetic lineages that come to represent the future of the human race?
Well, they outnumber us rich Westerners by about a hundred to 1. What do you think? Let me turn the question on you - with Western birth rates declining precipitously, what makes you think that it's our genetics that will represent the future of the human race? I mean, what would be the odds of that?
What if it turns out that having fewer children later in life actually increases their 'fitness' in terms of success in human society?
But that's not how fitness is defined. See, I think that's where your error lies. "Fitness" is a measure of how an individuals genes come to dominate a population. If you have only one child, you are substantially less fit than the couple down the street with many, many children.
I just think that fitness is relative and for humans it is coming to be defined differently than for other organisms.
This is species centrism at its worst. Why do you think the rules of evolution are different for us, just because we know how they work?
Fitness is fitness, if we're talking about evolution. It's not a measure of your wealth, or your place in life; it's a measure of how your genes come to either dominate the population or are removed from it. It doesn't matter how - the woman who opts never to bear children by taking birth control is just as unfit as the child who died of a genetic disorder before puberty.
Who is more likely to be taken out by the next Ebola outbreak or bird flu epidemic? My two daughters in Canada, or the 14 kids of Emilio Sanchez in Nicaragua?
Honestly? Pandemic flu killed millions in the 20's. Living in Canada or whereever else you think is rich enough isn't going to be enough. Among children, a reasonable estimate is 50% mortality. So you'll have 1 kid left, maybe none; Emilio will have around 6-7.
We don't need to produce as many shildren in the developed world to have greater fitness than those people because our juvenile mortality rates are much lower.
But the higher juvenile mortality of the developing world isn't enough to offset the difference. Their populations are growing markedly; ours are in decline. That suggests a very obvious evolutionary trend, albiet one that's rather uncomfortable to people like you and I. But the only alternative is pretending like evolution works differently for humans, and then scratching our heads in puzzlement when it turns out we were wrong about that.

This message is a reply to:
 Message 13 by EZscience, posted 05-03-2006 11:08 AM EZscience has replied

Replies to this message:
 Message 15 by EZscience, posted 05-03-2006 1:27 PM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 16 of 58 (308787)
05-03-2006 1:39 PM
Reply to: Message 15 by EZscience
05-03-2006 1:27 PM


By enhancing the survival of premature babies, we are necessarily improving the survival of any genes that are associated with premature birth.
What genes are, though? I'm asking because I don't know.
I am just not as confident as you that simple *numbers* of offspring are going to translate directly into the best genetic representation across multiple generations ofr all human beings, regardless of their situation.
If not numbers, then what? We're talking about evolution, remember? Not subjective ideas about what genes are "better" than others. We're talking about the change in allele frequencies in human populations. That's necessarily going to be informed by the sizes of populations and the numbers of individuals that have certain genes.
Those individuals laying fewer eggs end up with the higher fitness in this scenario. There are lot of other ways this sort of thing can occur.
No, I get that. But we're still talking about numbers - the latter organism still has more copies of their genes in the gene pool. That's not happening to individuals living in the West.
Are you saying that wealth or social status cannot, or will never, influence human fitness?
No, I'm saying the influence is abundantly clear - the wealthy reproduce a lot less. Wealth is maladaptive.
Out of all the soldiers dying in Iraq, how many are grunts versus hihgly-educated officers?
Many, many more. How many of those grunts are leaving behind 3 or 4 children? How many of those officers are leaving behind 1, or 2, or none at all? The more educated you are, the less children you tend to have.
How many rich Republicans like of dubya have avoided the draft entirely or been posted to safe places because of their family connections?
Plenty. How many children does W have? How large was his family before him?
Yes, that much is true, although I would say ours are stabilizing, not declining.
Well, you could say that, but you would be wrong. Our populations birth rates have largely fallen below the death rate; in other words, we have negative population growth. And in the West, that hardly represents a regression to K; our biomes could support many, many more human beings than they do now, particularly in America. We're not coming into equilibrium with our environment, our lifestyle choices are putting our population in decline.
In contrast, their ecology and economies could collapse from the burden of overpopulation and their populations plummet from pestilience, disease and starvation (just as in Africa right now).
Africa's population growth is the fastest of any reigon in the world. Like I've been saying you really need to be looking at the reality of human population growth.

This message is a reply to:
 Message 15 by EZscience, posted 05-03-2006 1:27 PM EZscience has replied

Replies to this message:
 Message 17 by EZscience, posted 05-03-2006 2:09 PM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 18 of 58 (308801)
05-03-2006 2:34 PM
Reply to: Message 17 by EZscience
05-03-2006 2:09 PM


Re: Numbers aren't everything.
Differential survival rates, however caused.
Survival is irrelevant. Everybody dies, after all. What's relevant is reproduction, and we aren't doing that much of it here in the West. That's evidence of reduced fitness.
. Ever think that the wealthy might be able to afford to reproduce less without a loss of much fitness because the survival and reproductive success of their offspring is far more assured?
Yeah, I did think this, EZScience. And then I looked at the data. And what I saw was that Western populations are in decline, and populations in "developing" reigons are growing sharply.
The data disproves your speculation, EZ. That's what I'm trying to get at, here. If the avaliability of better health care etc. to the wealthy was offsetting their lower birth rates, they'd have comparible population growth.
But they don't. Ergo, we know that being wealthy in the West isn't enough to offset the reduced birth rate.
But really, Crash - I can't spell it out any better.
Its not just how many children you have, but how many survive to produce children that also have a chance to survive to reproduce.
No, EZ, I get that. What you don't seem to get yet is that it still doesn't matter. The greater percentage of offspring that survive to parenthood in the West still doesn't offset the greater absolute birth rate in developing nations. And, again, the proof of this is the declining birth rate in the West, a trend that began decades ago and has only accellerated since.
This message has been edited by crashfrog, 05-03-2006 02:34 PM

This message is a reply to:
 Message 17 by EZscience, posted 05-03-2006 2:09 PM EZscience has replied

Replies to this message:
 Message 19 by EZscience, posted 05-03-2006 2:59 PM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 20 of 58 (308809)
05-03-2006 3:25 PM
Reply to: Message 19 by EZscience
05-03-2006 2:59 PM


Re: Numbers aren't everything.
I would argue that achieving comparable population growth would not be in the best interest of our long term fitness.
Evolution doesn't plan ahead, so our "long-term fitness" is irrelevant. We're shaped by the environment we live in now, not the environment future individuals might inhabit.
You seem totally fixated on birth rates.
I'm "fixated" on the relevant facts, something you seem prepared to completely dismiss. The facts are, the alleles of the developing world are increasining in frequency across the human gene pool, while the alleles of the West are decreasing in frequency.
That's it. End of story. That's evolution. If you want to talk about fitness, that's the fitness. Our alleles represent less fitness because they're being selected out of the population over time.
I have pointed out that there are many other factors that will ultimately limit the fitness of various populations above and beyond their birth rate, and that a high population birth rate may be ultimately detrimental to the future fitness of individuals within those populations.
Maybe. Maybe not. Regardless, it's irrelevant. That's a possible future environment. Our environment right now selects against alleles whose carriers live in the West.
That's it. End of story.

This message is a reply to:
 Message 19 by EZscience, posted 05-03-2006 2:59 PM EZscience has replied

Replies to this message:
 Message 21 by EZscience, posted 05-03-2006 3:52 PM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 22 of 58 (308841)
05-03-2006 5:11 PM
Reply to: Message 21 by EZscience
05-03-2006 3:52 PM


Re: New story, in that case
If we are talking about the trajectory of human evolution, how is our long term fitness in geographically separate populations NOT relevant?
Because we can't predict that environment; we can only observe the current environment. You're speculating from things you cann't possibly know. I'm merely projecting from what facts are known, now.
Please show me a fact that I am dismissing.
The facts of what populations are now increasing, and what populations are now decreasing. You've consistently handwaved this reality away.
Only if you consider the 'human gene pool' to be one effective population 'N(sub)e', which it isn't.
It is, moreso now than at any other time. It's a "global village." There's no reproductive isolation for any but the most marginal subpopulations. There's certainly no isolation for the major human ethnic groups. People are travelling all over the world, and having sex when they do. That's gene flow.
Except for the fortunate emigrants that get to join the gene pool in developed countries, most of their progeny remain 'in situ' with increasingly bleak prospects for the survival of their alleles, regardless of how quickly they replicate them.
Again, a completely erroneous statement. We know that this is not true, because regions like Africa have had consistently high growth rates for generations, now. Prospects for the survival of a large number of progeny are very high in those countries. That's a completely, totally different thing than the prospects for having a decent life, which is the distinction I'm trying to get you to see.
You haven't said one word about 'selection' yet. Your entire argument has hinged on differential birth rates.
How do you think we detect selection? The change in populations.
*I* am the one arguing that differential survival through various forms of selection can potentially render current differences in birth rates ultimately meaningless.
And I haven't disagreed with the potential of that being the case. But the reality is, there's no such counterselection occuring. This is proven by the differential in population growth.
You're talking about potential. I'm telling you what is real. It's pretty simple.
So tell me please, what is this environmental force that is causing our genes to be 'selected out' of the population?
The avaliability of birth control and social factors that lead people to believe that having fewer children is better than having many, or that having them later in life is better than having them sooner. The "environment" is that people are choosing to have less children, and have them later in life, here in the West.
I mean, duh. What did you think it was?

This message is a reply to:
 Message 21 by EZscience, posted 05-03-2006 3:52 PM EZscience has replied

Replies to this message:
 Message 23 by EZscience, posted 05-03-2006 10:15 PM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 24 of 58 (308929)
05-03-2006 10:47 PM
Reply to: Message 23 by EZscience
05-03-2006 10:15 PM


Re: New story, in that case
The earth isn’t approaching unsustainable population growth. Global warming and habitat destruction isn’t going to make survival more difficult for those in developing countries? You sure you want to contest this?
Why would I contest it, when it proves my point?
Current differences in rates of population increase may have little to do with the ultimate genetic makeup of the future human race.
Which ultimate? Who said anything about "ultimate"? What makes you think that the factors you're talking about will be the last factors to influence human genetics? That is what you're asserting, is it not? I mean, what else does "ultimate" mean?
What is undisputable is that the factors that I've described have been going on long enough to already be shaping our current genetics (in ways we don't yet know anything about.) It's the present we're talking about, not the unknown future.
You’re saying that everyone has an equal chance to mate with anyone else of the opposite sex wherever they are in the world? Because that’s the definition of effective population size.
Funny, I missed that definition in Genetics. Could you cite that, please?
That group of individuals that has a non-zero possiblity of interbreeding.
Er, wait. Now, which was it? An equal chance? Or a non-zero chance? Do you think you could refrain from contradicting yourself in the space to two sentences? It makes your posts very hard to follow. The discussion would proceed more readily if you made a greater effort to be clear.
You mean the ones with the highest birth rates you referred to?
Does a massive, growing, expanding, emigrating population sound like something I would describe as "marginal" to you?
No, I don't mean those. I was referring to tiny insular populations like the Pennsylvanian Amish, or Jewish populations that are strict about their members marrying within dogma.
Seriously. Is this a discussion you're really interested in having? Because it's starting to look like you're more interested in jerking me around.
But for how much longer can this be sustained before it reaches an asymptote, in your educated opinion ?
Why does it matter? We're talking about what's going on now, not what might happen in the future.
We hypothesize a selective force and design an experiment to test for its influence, neither of which you have managed to do.
Are you even reading my posts?
What is your hypothesis regarding the mechanism of *selection* that dooms us to genetic extinction in the western world?
You're not even reading them, are you?
You are trying to infer the action of selection a posteriori without even postulating a mechanism.
If you're already tuning me out only 20 posts in, what hope is there for discussion with you?
Which you apparently conclude can continue ad infinitum.
Ad infinitum? When did I say that? I don't know who you're arguing with at this point, EZ, because you're sure not responding to anything I'm writing. What on Earth gave you the idea that I thought this would go on forever?
Now you need to provide convincing evidence that these behavior patterns will inevitably lead to reduced average fitness of the local human population.
There's really no hope that you've actually been reading my posts at all, is there.

This message is a reply to:
 Message 23 by EZscience, posted 05-03-2006 10:15 PM EZscience has replied

Replies to this message:
 Message 27 by EZscience, posted 05-03-2006 11:16 PM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 26 of 58 (308937)
05-03-2006 11:09 PM
Reply to: Message 25 by nator
05-03-2006 11:07 PM


Because women are gold-digging bitches?
Seriously, Schraf, that's a stereotype that I'm shocked to see you perpetuate.

This message is a reply to:
 Message 25 by nator, posted 05-03-2006 11:07 PM nator has replied

Replies to this message:
 Message 28 by nator, posted 05-03-2006 11:21 PM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 29 of 58 (308946)
05-03-2006 11:37 PM
Reply to: Message 27 by EZscience
05-03-2006 11:16 PM


Re: New story, in that case
Crash, I have read every word of your posts and you haven't postulated any selective mechanism.
Post 22. That was like 5 posts ago.
What's wrong here?
I simply meant that the proximal trends you point to cannot be used to imply long term outcomes.
Who said anything about long-term? Sure, things are going to change. I get that, EZ.
So what? You offered the way things might be in the future to counter how things are now. How does that make any sense to you?
Populations are declining in the West and increasing, dramatically, in the developing world; that's changing the allele frequencies in the human species and isn't being counteracted by a ecologically-driven population crash in the developing world because that isn't happening yet.
Seriously. How hard is this to follow?
Since the genes of a Zimbabwe hooker have little chance of recombining with yours (presumably) you are both members of different 'effective' populations. Technically, you amay belong to the same gene pool, but functionally you don't. That's the point.
So, no Africans ever leave Africa? No American goes to Zimbabwe? No Somali immigrant in Minnesota has ever married and had children outside her culture?
If we're talking about me, personally, there's little if any chance of my genes recombining with anybody but my wife's, anbd likewise for her. Are you telling me that we don't belong to any reproductive population at all? That we're, essentially, our own species?
You're not making any sense. You're certainly not looking at the reality.
I thought one of the main reasons we were interested in evolutionary biology was because it gave us some insights into what to expect of living things in the future, based on what we understand about the forces shaping their biology. Is this not the case?
It's certainly the case that you seem to have completely lost track of what we were talking about. You were defending this position, if you'll recall:
quote:
We are severely suppressing selection on the human gene pool by enhancing everyone's reproductive success.
I mean, you pretty much seem to have completely abandoned this position, instead choosing to argue, ludicrously, that selection is working against people who live in Africam, despite their genes increasing in frequency in the human gene pool.
How is that a claim I'm supposed to take seriously?
With every post your replies seem to get more flippant.
I'm getting frustrated because you've chosen to repay my attempt to engage you in interesting debate with nonsense. To substitue evidence with speculation. And to consistently misconstrue my posts, even though anybody can go back less than 5 posts and see how I precisely answered the questions you claim I haven't.
I'm being just as polite as you deserve. If you don't appreciate the tenor that this "discussion" is headed towards, make the effort to modify your own behavior and start addressing the discussion honestly. I've already told you where to start. It's not hard.
What is this selective force you refer to that is eliminating the alleles of western people from the global gene pool?
Post 22. 5 posts ago. How hard is it to read? I've more than answered this question.
Your inference that higher birth rates rates in certain populations would inevitably translate into higher fitness in those populations.
"translate into?" That's what fitness is. Those populations are growing. Ours are declining. Their alleles are more frequent, and ours are less, over time. That's fitness. What happens in the future might change the fitness, but that's not a rebuttal because it hasn't happened yet.

This message is a reply to:
 Message 27 by EZscience, posted 05-03-2006 11:16 PM EZscience has replied

Replies to this message:
 Message 31 by crashfrog, posted 05-03-2006 11:48 PM crashfrog has not replied
 Message 32 by EZscience, posted 05-04-2006 5:43 PM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 30 of 58 (308948)
05-03-2006 11:39 PM
Reply to: Message 28 by nator
05-03-2006 11:21 PM


How is that different from men as a group being attracted to young women no matter how old they themselves get?
You mean, how is one dismissive, throwback gender stereotype different than the first? Not really that different, I guess.
When you say "men as a group" I read that as "every single man."

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 Message 37 by U can call me Cookie, posted 05-05-2006 10:56 AM crashfrog has not replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 31 of 58 (308953)
05-03-2006 11:48 PM
Reply to: Message 29 by crashfrog
05-03-2006 11:37 PM


Re: New story, in that case
Example: A subpopulation of green wibble-wobbles mutate an allele that provides fur. Is that an increase or a decrease in fitness?
It depends on whether or not they live in the Arctic circle or the Sahara desert. In fact, it may even depend on factors we know nothing about (like, whether or not wibble-wobbles like the cold). If the fur allele increases in frequency over time, we know that the allele represents an increase in fitness. If it decreases, we know it represents a decrease in fitness. Let's say that it increases.
Therefore, we know that having the allele means greater fitness. But let's say that you have a crystal ball, and you know that in 200 years global warming will change their environment from chilly Arctic temperatures to balmy tropical ones. At that time, fur will be a liability and (again, from your crystal ball) we know that the allele will begin to decrease in frequency, and therefore that having it represents a decrease in fitness.
So, does the allele mean more or less fitness? The answer is: both-
1) Greater fitness now;
2) Lesser fitness sometime in the future.
Do you understand that I'm talking about now, and you're trying to rebut that with what might happen in the future?
Do you understand that the fitness of an allele in the future, when conditions are different, is not relevant to looking at the fitness of that allele now, under present conditions?
I don't know how to make it any simpler than that. Am I still not making any sense to you?
This message has been edited by crashfrog, 05-03-2006 11:49 PM

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crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 38 of 58 (309374)
05-05-2006 12:02 PM
Reply to: Message 32 by EZscience
05-04-2006 5:43 PM


Re: New story, in that case
In post 22 your only reference to selection is:
So, you completely missed this exchange?
EZscience writes:
So tell me please, what is this environmental force that is causing our genes to be 'selected out' of the population?
Crashfrog writes:
The avaliability of birth control and social factors that lead people to believe that having fewer children is better than having many, or that having them later in life is better than having them sooner. The "environment" is that people are choosing to have less children, and have them later in life, here in the West.
Are you done being ridiculous, now?
Their replication might be slower, but that doesn't amount to any form of selection against them.
Non-random differential reproduction is selection, by definition. I've already put forth the causal mechanism (in two posts, now.) Humans in the West are being selected against, detectable by the fact that our genes represent a decreasing frequency within the human gene pool.
'Yet' being the pivotal word. I agree with you here, but I think you will agree there are many independent lines of evidence to suggest that many of these populations will have to crash eventually. What happens to the alleles they contain at that point is uncertain and will depend on emigration, survivorship, etc. but I predict some severe bottlenecks.
Sure. Granted.
So what? The fitness of these genes in a future environment is irrelevant to their fitness in this environment.
You seem to view the human species as one large homogenate, whereas I see it more as a series of ecologically separate populations that have potentially very different fates, regardless of a little gene fow between them, hence my comments on effective population size.
That doesn't seem to be born out by the data (and again we see how you prefer to substitute your own speculations for actual evidence.) The evidence indicates that genetic differences between these populations are decreasing, not increasing, and that's understood to be a function of how transportation technologies mean that these populations are becoming decreasingly geographically seperated.
No, we are not separate species
Could you stop being evasive and actually answer my questions as I ask them? Quote mining me isn't going to get you very far. Here's what I asked you:
quote:
If we're talking about me, personally, there's little if any chance of my genes recombining with anybody but my wife's, anbd likewise for her. Are you telling me that we don't belong to any reproductive population at all? That we're, essentially, our own species?
And here's what you quoted:
quote:
Are you telling me that we don't belong to any reproductive population at all? That we're, essentially, our own species?
And then here's what you answered:
No, we are not separate species, but we are functionally separate societies in relatively separate ecosystems and hence our gene pools, even with some gene flow, are subject to locally specific differences in selective forces.
Did you think I wouldn't notice? Go back and answer the question that I asked.
Not at all. It was a different issue, one of medical intervention increasing the ”genetic load’ of our population.
Different issue? That's the topic of this thread.
What do you think we're talking about, exactly? I'm asking because if you're laboring under a drastically different idea of what the topic is, here, that might explain why your posts have so consistently seemed to be evading my arguments.
As I have pointed out, there is every reason to believe that all kinds of negative selective forces are starting to affect survival in Africa, but until they start reducing more of the survival prior to reproductive age, you are not going to see much effect on population growth.
Survival past reproduction is not relevant to fitness, so your attempt to make an argument from unknown factors is kind of pointless. Unless reproductive success is being affected, the force is not selective. A disease that kills only the extremely elderly, for instance, is not a selective force.
At least I have managed to refrain from insulting you.
Are you kidding me? Your constant attempts to misrepresent me, and your quote mining in this message, are an insult to my intelligence. Why is it that you refuse to approach this discussion honestly? I was being perfectly polite until you started acting like an ass. Like here, where you misrepresent me again:
Like war for example. I guess I don’t accept your inference that somehow we in the west will inevitably lose genetic representation in the human race just because there are poor countries breeding faster than we are.
Inevitably? That was never my position. It's merely my position that that is what is happening now, and you've presented nothing to rebut that.
Yes, they technically have higher Darwinian fitness measured by current rates of reproduction.
That's been my sole position all along. Are we done, now?

This message is a reply to:
 Message 32 by EZscience, posted 05-04-2006 5:43 PM EZscience has replied

Replies to this message:
 Message 39 by EZscience, posted 05-05-2006 2:11 PM crashfrog has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 40 of 58 (309419)
05-05-2006 2:40 PM
Reply to: Message 39 by EZscience
05-05-2006 2:11 PM


Re: New story, in that case
So now I am pondering whether we would have to accept abstinance and suicide as forms of 'selection' if we accept birth control availability.
Sure. Abstinence doesn't work, though, so we can throw that right out. People who claim to be "abstinent" don't have any less sex than anybody else.
Suicide? The largest cause of suicide is, of course, depression; and we know that depression is related to chemical states in the brain. It's not outside of the realm of possibility to suggest that a gene exists which, previously, had represented negative fitness for its carriers (by making them kill themselves) and been selected against, but now in the presence of SSRI drugs, no longer represents negative fitness.
You are inferring the action of selection without demonstrating it.
The changing gene frequencies demonstrates it, and I've provided the mechanism. As you've stated that's what you need to prove selection.
There are situations where both reduced fecundity and delayed onset of reproduction can evolve as a consequence of selection acting on other traits and actually be favored under selection.
How many times do I have to rebut this, EZ? Go back to the reality. What is the reality of the situation? What effect on our population is reduced fecundity and delayed reproduction having in reality? The population statistics are out there on the internet. Look them up and see for yourself.
You are using the term in its broadest sense without identifying any 'selective force'.
Posts 22 and 38. The selective force has been specifically identified to you, twice now. I'll remind you of the forum guidelines:
quote:
Avoid any form of misrepresentation.
Given that, it doesn't seem unreasonable to project certain changes in the mean fitness of particular populations based on their geographic locations.
Who said that was unreasonable?
I think you mean less genetically separated. The geography doesn’t change.
No, but its consequences for our species does change. Mountains and oceans cease to be meaningful barriers.
I meant what I said. The geographical separation of our populations is decreasing.
I'd like to hear what you have to say about post 36.
I'll address that post shortly. The long and the short of it is, we don't largely disagree.

This message is a reply to:
 Message 39 by EZscience, posted 05-05-2006 2:11 PM EZscience has replied

Replies to this message:
 Message 42 by EZscience, posted 05-05-2006 3:21 PM crashfrog has replied

  
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