Modern Humans And Evolution

[steve_bank]

Science, technology, cheap centralized energy, and abundant food has taken humans out of natural selection. We live in an environment that has no mechanism for natural selection.

Natural selection does not really apply to humans anymore. Childhood inoculations minimize disease that would kill off children with weaker immune systems and genetic deficiencies. Those born with genetic problems survive due to science and technology who would normally not survive childhood.

Those who would likely die young pass on bad genes and harmful mutations.

Through the first half of the 20th century people had many kids because only a few wuld survive.

 

[bilby]

Science, technology, cheap centralized energy, and abundant food has taken humans out of natural selection. We live in an environment that has no mechanism for natural selection.

People die, having had differing numbers of children.

Until that stops being true, you are wrong.

Natural selection does not really apply to humans anymore. Childhood inoculations minimize disease that would kill off children with weaker immune systems and genetic deficiencies. Those born with genetic problems survive due to science and technology who would normally not survive childhood.

Nonsense.

Technology is a part of the environment, and alters the selection pressures. It doesn't eliminate them.

Those who would likely die young pass on bad genes and harmful mutations.

If you don't fail to reproduce, then it's by definition not a bad gene or harmful mutation in your environment.

Through the first half of the 20th century people had many kids because only a few wuld survive.

That's true. It's also completely irrelevant to your other sophomoric points.

Before you talk about a subject, it would be wise to acquire a reasonable understanding of it.

The OP sounds like the sort of half-baked nonsense a twelve year old comes up with the first time he hears about evolution.

 

[untermensche]

Since human survival has been enhanced by human technology natural selection has been altered considerably.

Many individuals are able to reproduce that would not have even existed without human technology.

The process has been altered.

No doubt.

The ability to survive has been enhanced and traits that would have been wiped away remain.

But there are still limits as to who can reproduce.

Generally those with severe cognitive deficits do not reproduce.

And there are other rare exceptions.

So natural selection is still in place but survival has been enhanced so a wider genetic diversity is possible.

But humans are a temporary blip. In geological time they will all be gone soon.

 

[rousseau]

I think what you're trying to say is that speciation is unlikely, which is probably true at least for a very long time. But we're certainly still evolving and changing.

 

[Jokodo]

Since human survival has been enhanced by human technology natural selection has been altered considerably.

Indeed. Stone tools made blunt teeth much less of an issue, while agriculture increased the importance of being able to digest large quantities of starch from almost irrelevant to critical.

Or are you under the impression that technology is something that only started in the last 200 years?

Many individuals are able to reproduce that would not have even existed without human technology.

It's "worse" than that: *only* individuals that would not have existed without human technology are able to reproduce -- because none that would have lived for 100s of thousands, if not millions, of years.

The process has been altered.

No doubt.

The ability to survive has been enhanced and traits that would have been wiped away remain.

As is the case with almost any other species. Adult trees significantly shape the environment in which saplings grow, some tree species poison the ground so other species can't compete, corals grow on top of a pile of skeletons of their great-great-grandparents...

But there are still limits as to who can reproduce.

Generally those with severe cognitive deficits do not reproduce.

And there are other rare exceptions.

Rare exceptions? Around a quarter of the population do not reproduce (somewhat more for men, somewhat less for women).

So natural selection is still in place but survival has been enhanced so a wider genetic diversity is possible.

You know what's also been enhanced? Transportation.

But humans are a temporary blip. In geological time they will all be gone soon.

This may or may not be the case, and none of us will be there to see it, but it's irrelevant for the current context.

 

[untermensche]

Indeed. Stone tools made blunt teeth much less of an issue, while agriculture increased the importance of being able to digest large quantities of starch from almost irrelevant to critical.

Agriculture changed the landscape and allowed the human population to expand greatly. But I'm talking about things like insulin

Millions of people now surviving to reproductive age that would have died in the near past.

A genetic defect overcome by technology.

Rare exceptions? Around a quarter of the population do not reproduce (somewhat more for men, somewhat less for women).

Not due to any specific genetic problem.

The rare exceptions I speak of are things that prevent a person from being able to reproduce.

I'm not talking about mere contingency of circumstance such that reproduction does not occur.

 

[Jokodo]

Indeed. Stone tools made blunt teeth much less of an issue, while agriculture increased the importance of being able to digest large quantities of starch from almost irrelevant to critical.

Agriculture changed the landscape and allowed the human population to expand greatly. But I'm talking about things like insulin

In what way are "things like insulin" categorically different from things like blunt, stubby teeth?

Millions of people now surviving to reproductive age that would have died in the near past.

True. It's also true that millions of people surviving 100s of years ago would have died 1000s of years ago, and basically everyone surviving 1000s of years ago would have died millions of years ago.

It's even probable that mostly everyone surviving a million years ago would have died a million and a half years ago. Environments change, partly due to external causes and partly due to the actions of conspecifics. None of that is new, and none of that is specific to humans, let alone modern humans. I'm not even sure humans are top of the pile when trying to quantify the share of shaping the environment that can be attributed to conspecifics, though we certainly come close, and closer now than a few hundred years ago.

A genetic defect overcome by technology.

Rare exceptions? Around a quarter of the population do not reproduce (somewhat more for men, somewhat less for women).

Not due to any specific genetic problem.

The rare exceptions I speak of are things that prevent a person from being able to reproduce.

I'm not talking about mere contingency of circumstance such that reproduction does not occur.

Not being able to find a partner willing to reproduce with you (or with whom you're willing to reproduce) is not necessarily "mere contingency" anymore not being eaten by a lion is. Natural (and sexual) selection isn't much more than "mere contingency" averaged over large numbers. A mouse that fails to show fear of cats may not be eaten today; it may not be eaten tomorrow; it may not be eaten at all. A person who planned to only have one child may get pregnant with triplets. As long as those who fail to reproduce by mere contingency have different heritable traits on average from those who do, selection occurs. It's a numbers game.

 

[untermensche]

In what way are "things like insulin" categorically different from things like blunt, stubby teeth?

Blunt stubby teeth are not lethal genetic defects.

The lack of insulin is.

Not being able to find a partner willing to reproduce with you (or with whom you're willing to reproduce) is not necessarily "mere contingency" anymore not being eaten by a lion is.

It is nothing but mere contingency for most. They do not fail to reproduce due to some inherent inferiority. It is mere contingency. Bad luck. Like getting killed by a lion.

The contingencies of existence do not always favor the fastest or the smartest or the strongest.

But if you cannot reproduce due to major defects that is something else entirely.

With enough humans reproducing the mere contingencies like not finding a mate become meaningless in terms of most genetic information. But some serious defects are removed because the person with it cannot reproduce.

But if lethal defects are allowed to persist due to human technology, like the development of insulin, that is human alteration of the gene pool, not natural selection.

 

[steve_bank]

I think what you're trying to say is that speciation is unlikely, which is probably true at least for a very long time. But we're certainly still evolving and changing.

We are socially growing by social natural selection. The failure of global communism and the success of the western systems.

Muttaions occur and are passed on, but there is little in the way of selection to promote benficial mutations over other genes. The impact of passing on bad genes is lessend by tyhe large gene pool and wide open mating.

Procreation has to favor those new beneficial mutations for an evolutionary step by selection.

 

[bilby]

I think what you're trying to say is that speciation is unlikely, which is probably true at least for a very long time. But we're certainly still evolving and changing.

We are socially growing by social natural selection. The failure of global communism and the success of the western systems.

Muttaions occur and are passed on, but there is little in the way of selection to promote benficial mutations over other genes. The impact of passing on bad genes is lessend by tyhe large gene pool and wide open mating.

Procreation has to favor those new beneficial mutations for an evolutionary step by selection.

There are no 'bad' or 'beneficial' genes. There are genes that succeed, and those that fail. As long as there are people who don't have offspring, and people who do, evolution is inevitable.

Your entire thesis is based on a dreadful caricature of evolution, rather than on the actual theory. You should stop commenting on evolution until you have learned and understood what it says (and what it does not say); Unless you enjoy being thought a fool.

 

[Jokodo]

In what way are "things like insulin" categorically different from things like blunt, stubby teeth?

Blunt stubby teeth are not lethal genetic defects.

The lack of insulin is.

Blunt stubby teeth are not a lethal genetic defect when you have tools to help you mince your food. Otherwise, they might well be.

The lack of insulin is not a lethal genetic defect when you have tools to help you control your blood sugar level. Otherwise, it might well be.

In both cases, it's technology that makes something that otherwise would be lethal -- trivial. Your failure to acknowledge things that were invented before 1850 as technology does not change the fact that they've altered selection pressures as much as thing that were invented after, and remains your failure alone.

Not being able to find a partner willing to reproduce with you (or with whom you're willing to reproduce) is not necessarily "mere contingency" anymore not being eaten by a lion is.

It is nothing but mere contingency for most. They do not fail to reproduce due to some inherent inferiority. It is mere contingency. Bad luck. Like getting killed by a lion.

The contingencies of existence do not always favor the fastest or the smartest or the strongest.

But if you cannot reproduce due to major defects that is something else entirely.

With enough humans reproducing the mere contingencies like not finding a mate become meaningless in terms of most genetic information. But some serious defects are removed because the person with it cannot reproduce.

Quite the contrary: With enough humans (not) reproducing, patterns emerge in what you call "mere contingencies" that add up to significant selection pressures. You don't have to be able to pin down why any specific individual did or did not reproduce -- as long as the ones who do have different heritable traits on average from the ones who don't, selection happens.

But if lethal defects are allowed to persist due to human technology, like the development of insulin, that is human alteration of the gene pool, not natural selection.

I guess then living in herds for mutual protections, and those herds preventing shrubbery from growing with their grazing behaviour, is wildebeest alteration of the gene pool and not natural selection?

 

[Keith&Co.]

Science, technology, cheap centralized energy, and abundant food has taken humans out of natural selection. We live in an environment that has no mechanism for natural selection.

Ah.
Do you get your flu shot every year?

Do you ever spend much time THINKING about that, that there's a NEW flu vaccine EVERY YEAR?

 

[rousseau]

I think what you're trying to say is that speciation is unlikely, which is probably true at least for a very long time. But we're certainly still evolving and changing.

We are socially growing by social natural selection. The failure of global communism and the success of the western systems.

Muttaions occur and are passed on, but there is little in the way of selection to promote benficial mutations over other genes. The impact of passing on bad genes is lessend by tyhe large gene pool and wide open mating.

Procreation has to favor those new beneficial mutations for an evolutionary step by selection.

Evolution doesn't have any kind of 'progressive directionality'.. the direction it moves is the direction it moves.

'Beneficial mutations' are anything that leads to more babies given the current social/environmental context, *not* what makes humans as a whole flourish.

 

[braces_for_impact]

I think what you're trying to say is that speciation is unlikely, which is probably true at least for a very long time. But we're certainly still evolving and changing.

We are socially growing by social natural selection. The failure of global communism and the success of the western systems.

Muttaions occur and are passed on, but there is little in the way of selection to promote benficial mutations over other genes. The impact of passing on bad genes is lessend by tyhe large gene pool and wide open mating.

Procreation has to favor those new beneficial mutations for an evolutionary step by selection.

Why do I get an unsettling feeling of where this line of "inquiry" is going?

 

[Keith&Co.]

Why do I get an unsettling feeling of where this line of "inquiry" is going?

Guessing it's because others have used similar arguments to reach unsettling conclusions...

 

[Jobar]

Our technologies have changed the selection pressures that act on us, but we're still being selected by our environment.

It's possible that we will be able to 'steer' some of the changes to our genome, via genetic engineering. But we'll still be evolving.

 

[rousseau]

We could just not worry about it, but I'm sure some charismatic college dropout with rich parents and a God complex will pull out some test tubes.

 

[Keith&Co.]

But we'll still be evolving.

Hey, even if we're not... Is there anything that REQUIRES us to evolve?
If we come to be in complete control of the environment, and establish a stable genetic profile for each generation... Is there anything particularly wrong with that?

Crocodiles and sharks haven't changed much in a long, long time. Some creationists try to claim that's evidence against evolution, but they're just really, really well adapted to their environments. What if we moved off of Earth, lived in completely controlled habitats, where the environment is really, really well adapted to us? And ensured that any given allele shows up with the same frequency, generation after generation, after generation?

What cosmic rule would be violated?

 

[skepticalbip]

There is no evidence that the passenger pigeon is still evolving. I think we have discovered the way to stop species from evolving.

 

[bilby]

Why do I get an unsettling feeling of where this line of "inquiry" is going?

Guessing it's because others have used similar arguments to reach unsettling conclusions...

I thought we had resolved that back in 1945. It turned out that they were wrong - even by their own highly questionable methodology that said that the weak would not survive, and that the strong would inevitably prevail.