Has humanity left evolution behind?

[diebitter]

I suspect in this technological age, it's mostly left behind - until the next big epidemic that favours a certain type of immune system, or some climatic change gives some gene a distinct advantage...

Sexual selection I'm sure was a powerful force in creating the current racial types (I suspect the eye shape of oriental races was seen as powerfully attractive at some point in their history, for example, and so spread quickly by the rich guys who had huge families with the most attractive women...). But with contraception etc, I suspect the most beautiful no longer have the most children....

So, is evolution still a power on humankind or not?

What you think?

[Brom]

Evolution always occurs. It is neither for the better or worse for the species involved, it is aimless. You probably realised this, but one of your last sentences ("... I suspect that the most beautiful no longer have the most children"), seems to suggest that you think evolution only happens to better a species.

On another note, I think that we haved slowed down the power that evolution has over our genes. We are now able to manipulate genes manually and produce changes that would have typically taken thousands or even tens of thousands of years before. Hopefully changes like these will allow us to make up for poor evolutionary traits that society have introduced by keeping our sick and genetically deficient around longer than nature would allow.

[diebitter]

[ QUOTE ]
Evolution always occurs. It is neither for the better or worse for the species involved, it is aimless. You probably realised this, but one of your last sentences ("... I suspect that the most beautiful no longer have the most children"), seems to suggest that you think evolution only happens to better a species.

[/ QUOTE ]

No that sentence was specifically talking about the negation of the power of sexual selection (well at least in terms of appearance) as an effector in human evolution.

[MidGe]

I think there simply has been a new mechanism in evolution. The ability to preserve and communicate from generation to generation. A simple by-product of brain development, yet very significant in survival terms, at least for a while. /images/graemlins/smile.gif

[diebitter]

[ QUOTE ]
I think there simply has been a new mechanism in evolution. The ability to preserve and communicate from generation to generation. A simple by-product of brain development, yet very significant in survival terms, at least for a while. /images/graemlins/smile.gif

[/ QUOTE ]

This is cultural evolution, or 'memetics (http://en.wikipedia.org/wiki/Memetics)', a pretty interesting field in its own right.

[FlFishOn]

I always liked the phrase 'survival of the fittest' as in survival to reproduce. In that sense we're allowing many unfit genes to pass to future generations thanks to huge advances in medicine. The unfit are clearly reproducing today when they would not have done so 200 years ago.

There is still evolution. I'm against motorcycle helmet laws for the simple fact that those too stooopid to wear a helmet stand a better chance of failing to reproduce.

I'm against most all forms of welfare as these programs tend to propogate unfit genes. If you can't support yourself why are you reproducing? Is there any reason to think your ofspring will be more fit? I think not. Yes, there's a large environmental component but I'm sure there's at least a small genetic one as well.

[Rduke55]

Think about the large amounts of gene flow due to current immigration/emigration.
And I can't imagine that sexual selection still plays a huge role.

[Rduke55]

I think you need to read up more on evolution.
"Survival of the fittest" isn't the end all be all.

[xorbie]

evolution is by definition impossible to leave behind unless we get to the point where we are actually altering our own DNA in which case i suppose you could make the argument.

[bobman0330]

[ QUOTE ]
I'm against most all forms of welfare as these programs tend to propogate unfit genes.

[/ QUOTE ]

Yikes, mein Fuhrer.

[Rduke55]

I just saw a glaring typo in my post.
Should read "I can't imagine that sexual selection DOESN"T still play a huge role."
So, I agree we will never be away form evolution.

[Brom]

[ QUOTE ]
[ QUOTE ]
I'm against most all forms of welfare as these programs tend to propogate unfit genes.

[/ QUOTE ]

Yikes, mein Fuhrer.

[/ QUOTE ]

Welfare was introduced by Hitler.

[xorbie]

[ QUOTE ]

I always liked the phrase 'survival of the fittest' as in survival to reproduce. In that sense we're allowing many unfit genes to pass to future generations thanks to huge advances in medicine. The unfit are clearly reproducing today when they would not have done so 200 years ago.

There is still evolution. I'm against motorcycle helmet laws for the simple fact that those too stooopid to wear a helmet stand a better chance of failing to reproduce.

I'm against most all forms of welfare as these programs tend to propogate unfit genes. If you can't support yourself why are you reproducing? Is there any reason to think your ofspring will be more fit? I think not. Yes, there's a large environmental component but I'm sure there's at least a small genetic one as well.

[/ QUOTE ]

people who say "survival of the fittest" as if that's the be all and end all of evolution tend to be pretty ignorant. people who think your socioeconomic position (or something as mundane as not putting on a helmet) in this world is somehow an immediate indicator of your genetic "strength" tend to be ignorant of genetics.

i'm going to have to ask you not to have any children, your genes are clearly not up to the task. sorry.

[Borodog]

Rduke55,

Since it's your field, I wanted to run a thought I had past you.

Sexual selection can produce bizarre evolutionary results like the peacock's tail, as is well understood (because "fit" in evolutionary terms is more subtle than is at first apparent). I was thinking about the fantastic and often bizarre range of phenotypes that artifical selection by humans can create within another species, such as Canis familiaris. Isn't artificial selection by humans in dog breeding extremely similar to sexual selection within a species, especially in modern times when dogs are rarely bred for utilitarian traits and purposes but rather for bizarre whims of, essentially, fashion? Bizarre combinations of traits are well preserved because some humans find them "cute" or attractive.

How could you predict a chihuahua evolving from wolf stock without this mechanism, or a bright white breed with black spots that are often deaf, or giant wooly dogs that look more like bears than wolves? You can't of course. Given the short amount of time that humans have been selectively breeding dogs from their ancestral wolf stock, I have absolutely no doubt the given enough time there will be "dogs" the size of mice and bears, horses, or elephants.

Just a thought.

[Trantor]

Look at world infant mortality figures....very strong evolutionary pressures presumably are still present in these places. The minority of wealthy fit people may feel evolutionary pressures seem absent but evven in an advanced society, evolution will still be an active process.

http://www.cia.gov/cia/publications/factbook/rankorder/2091rank.html

[Rduke55]

[ QUOTE ]
(because "fit" in evolutionary terms is more subtle than is at first apparent).

[/ QUOTE ]

A terrific point that very few people that consider themselves educated on evolution get.

I was thinking about the fantastic and often bizarre range of phenotypes that artifical selection by humans can create within another species, such as Canis familiaris. Isn't artificial selection by humans in dog breeding extremely similar to sexual selection within a species, especially in modern times when dogs are rarely bred for utilitarian traits and purposes but rather for bizarre whims of, essentially, fashion? {/quote]

Yes. There are some wonderful similarities.


[ QUOTE ]
How could you predict a chihuahua evolving from wolf stock without this mechanism, or a bright white breed with black spots that are often deaf, or giant wooly dogs that look more like bears than wolves? You can't of course. Given the short amount of time that humans have been selectively breeding dogs from their ancestral wolf stock, I have absolutely no doubt the given enough time there will be "dogs" the size of mice and bears, horses, or elephants.


[/ QUOTE ]

This is a really interesting question. Some of the work I do deals with evolutionary constraints, specifically size constraints. Dogs are a great subject for this because of the amazing variation and I would imagine that if there was only the traditional wild dogs around we would probably predict constraints on it that have been surpassed by artificial breeding. I have been in discussions with people about constraints, specifically in dogs, and we just can't come to a consensus. A lot of me (and others) thinks that we're close, if not at, the lower size range for dogs (I have a decent idea of this subject as some of my work is on the masked shrew - the 2nd smallest mammal on the planet) but I would guess that we can go bigger - but I really don't know by how much. Scaling (especially one of my favorite subjects - brain scaling)is a tricky business.

I guess I haven't answered your question. I doubt we could get down to mouse-sized with dogs (the obvious point is "What about those tiny prehistoric horses?" but the scaling differences there may be more reasonable that the dog-mouse differences.) and I'd guess that maybe we could get 2x bigger, but that's just a guess.

[Rduke55]

[ QUOTE ]
[ QUOTE ]

I always liked the phrase 'survival of the fittest' as in survival to reproduce. In that sense we're allowing many unfit genes to pass to future generations thanks to huge advances in medicine. The unfit are clearly reproducing today when they would not have done so 200 years ago.

There is still evolution. I'm against motorcycle helmet laws for the simple fact that those too stooopid to wear a helmet stand a better chance of failing to reproduce.

I'm against most all forms of welfare as these programs tend to propogate unfit genes. If you can't support yourself why are you reproducing? Is there any reason to think your ofspring will be more fit? I think not. Yes, there's a large environmental component but I'm sure there's at least a small genetic one as well.

[/ QUOTE ]

people who say "survival of the fittest" as if that's the be all and end all of evolution tend to be pretty ignorant. people who think your socioeconomic position (or something as mundane as not putting on a helmet) in this world is somehow an immediate indicator of your genetic "strength" tend to be ignorant of genetics.

i'm going to have to ask you not to have any children, your genes are clearly not up to the task. sorry.

[/ QUOTE ]

This makes it look like I did the post you are responding to.

[FlFishOn]

You did a fine job of pegging me. I'm thinking you might have a future on the psychic hotline. Probably pays better than living in your mom's basement downloading porn.

[xorbie]

[ QUOTE ]

This makes it look like I did the post you are responding to.


[/ QUOTE ]

yeah sorry about that, i was just using quick reply

[xorbie]

[ QUOTE ]
You did a fine job of pegging me. I'm thinking you might have a future on the psychic hotline. Probably pays better than living in your mom's basement downloading porn.

[/ QUOTE ]

good response, my argument lays shattered beside the broken remains of my ego.

[Stereolab]

[ QUOTE ]
I always liked the phrase 'survival of the fittest' as in survival to reproduce. In that sense we're allowing many unfit genes to pass to future generations thanks to huge advances in medicine. The unfit are clearly reproducing today when they would not have done so 200 years ago.

There is still evolution. I'm against motorcycle helmet laws for the simple fact that those too stooopid to wear a helmet stand a better chance of failing to reproduce.

I'm against most all forms of welfare as these programs tend to propogate unfit genes. If you can't support yourself why are you reproducing? Is there any reason to think your ofspring will be more fit? I think not. Yes, there's a large environmental component but I'm sure there's at least a small genetic one as well.

[/ QUOTE ]

Um, thats Social Darwinism. It Has no affiliation with Darwin and Evolution.

Wiki: Social Darwinism (http://http://en.wikipedia.org/wiki/Social_Darwinism)


I know poker players look at the long run but damn you're really looking into the future.

[Borodog]

[ QUOTE ]
[ QUOTE ]
(because "fit" in evolutionary terms is more subtle than is at first apparent).

[/ QUOTE ]

A terrific point that very few people that consider themselves educated on evolution get.

[ QUOTE ]
I was thinking about the fantastic and often bizarre range of phenotypes that artifical selection by humans can create within another species, such as Canis familiaris. Isn't artificial selection by humans in dog breeding extremely similar to sexual selection within a species, especially in modern times when dogs are rarely bred for utilitarian traits and purposes but rather for bizarre whims of, essentially, fashion?

[/ QUOTE ]

Yes. There are some wonderful similarities.

[ QUOTE ]
How could you predict a chihuahua evolving from wolf stock without this mechanism, or a bright white breed with black spots that are often deaf, or giant wooly dogs that look more like bears than wolves? You can't of course. Given the short amount of time that humans have been selectively breeding dogs from their ancestral wolf stock, I have absolutely no doubt the given enough time there will be "dogs" the size of mice and bears, horses, or elephants.


[/ QUOTE ]

This is a really interesting question. Some of the work I do deals with evolutionary constraints, specifically size constraints. Dogs are a great subject for this because of the amazing variation and I would imagine that if there was only the traditional wild dogs around we would probably predict constraints on it that have been surpassed by artificial breeding. I have been in discussions with people about constraints, specifically in dogs, and we just can't come to a consensus. A lot of me (and others) thinks that we're close, if not at, the lower size range for dogs (I have a decent idea of this subject as some of my work is on the masked shrew - the 2nd smallest mammal on the planet) but I would guess that we can go bigger - but I really don't know by how much. Scaling (especially one of my favorite subjects - brain scaling)is a tricky business.

I guess I haven't answered your question. I doubt we could get down to mouse-sized with dogs (the obvious point is "What about those tiny prehistoric horses?" but the scaling differences there may be more reasonable that the dog-mouse differences.) and I'd guess that maybe we could get 2x bigger, but that's just a guess.

[/ QUOTE ]

Now I'm really intrigued. Clearly elephant evolved from animals that were the size of shrews, so what would stop dog stock from being able to scale up or down to the size of a shrew or an elephant? Or are you just saying that the evolutionary changes would have to be so large that we really couldn't call them "dogs" any more, because you'd have to get into the realm of completely different species?

Forgive me if this seems simplistic; I've never heard of the concept of evolutionary "constraints" before. What kinds of constraints? Like constraints on leg and foot morphology to support stupendous weights (horse and elephant legs and feet are incredibly highly specialized, for example), or some other kind of mechanism?

Thanks.

[Rduke55]

[ QUOTE ]

Now I'm really intrigued. Clearly elephant evolved from animals that were the size of shrews, so what would stop dog stock from being able to scale up or down to the size of a shrew or an elephant? Or are you just saying that the evolutionary changes would have to be so large that we really couldn't call them "dogs" any more, because you'd have to get into the realm of completely different species?

[/ QUOTE ]

Yeah, that's what I'm talking about.

[ QUOTE ]
Forgive me if this seems simplistic; I've never heard of the concept of evolutionary "constraints" before. What kinds of constraints? Like constraints on leg and foot morphology to support stupendous weights (horse and elephant legs and feet are incredibly highly specialized, for example), or some other kind of mechanism?

[/ QUOTE ]

Constraints are basically barriers to certain developments. There are some that are intrinsic, for example, there's size limitations on the mammalian brain - lower limits because you need a certain number of neurons to do what you need the mammalian brain to do, and upper limits - because the brain is metabolically expensive (many believe our unusually short digestive tract, etc. is the result of a trade off for the bigger brain), has to retain certain levels of connectivity (more neurons create serious "problems" in this regard), has to fit inside the skull, be carried around, etc.
There are also historical constraints which are called evolutionary constraints (although any constraint in an animals's evolution is often referred to as an evolutionary constraint). Stephen J. Gould did a pretty good treatment on why we have 5 toes on each foot (actually I think he talked fingers). Basically evolutionary history makes it much easier to keep certain traits. I have to run but it boils down to something like this - We have 5 toes because our ancestors had 5 toes, their ancestors had 5 toes, etc., etc., etc. - because structures are inherited, new structures must vary on older structures and the genes involved in patterning that stuff creates a barrier to certain variations.
Could the mammalian line have evolved with 6 toes on each foot? Easily, but because we did with 5, it's harder to get to 6. I'm not saying that there aren't examples with 6 (see polydactyly in the Amish) but the idea is that there's not this huge variation in toe number across species because of the constraint.

The take-home point is that while it's theoretically possible for a great number of traits to come about there are limitations to what can reasonably come about.

I'm not doing a great job explaining this because I'm in a hurry but this is a fascinating subject that definitely warrants more discussion.

[FlFishOn]

"There is still evolution. I'm against motorcycle helmet laws for the simple fact that those too stooopid to wear a helmet stand a better chance of failing to reproduce.

I'm against most all forms of welfare as these programs tend to propogate unfit genes. If you can't support yourself why are you reproducing? Is there any reason to think your ofspring will be more fit? I think not. Yes, there's a large environmental component but I'm sure there's at least a small genetic one as well.


--------------------------------------------------------------------------------



"Um, thats Social Darwinism. It Has no affiliation with Darwin and Evolution."


I'll give this one shot.

In America, poverty correlates with intelligence. It's not a huge number but I'd guess it's around .4 or so. There are only a few folks that insist intelligence has no genetic component while there are many that believe there is a modest to strong genetic component to it. I believe that any denial of a genetic component is agenda driven and mostly disingenuous.

So, if mostly stooopid people are breeding beyond their own means thanks to welfare then less welfare support might remove a portion of the associated 'stooopid' gene set from the population. It will not result in speciation but possibly some tiny improvement, assuming you think more intelligent is for the better (hint: sapiens).

[Stereolab]

[ QUOTE ]

In America, poverty correlates with intelligence. It's not a huge number but I'd guess it's around .4 or so. There are only a few folks that insist intelligence has no genetic component while there are many that believe there is a modest to strong genetic component to it. I believe that any denial of a genetic component is agenda driven and mostly disingenuous.



[/ QUOTE ]
Yes genetics plays a role but your neglecting another key component, environment. This could turn into a nature vs. nurture debate, but to claim that only one component exists is ignorant.

In the your first sentence, you are contradicting yourself. You say in America, poverty correlates with intelligence. I'm not sure of your source but if the correlation is genetic, why isn't the rest of the world included.

Also, you have to understand correlation only show relationship, not causality.

[FlFishOn]

"Yes genetics plays a role but your neglecting another key component, environment."

I failed to mention environment assuming anyone interested in debating this issue already understood that %genetic + %environmental = 100.

"In the your first sentence, you are contradicting yourself. You say in America, poverty correlates with intelligence."

My data is for US only.

"Also, you have to understand correlation only show relationship, not causality."

You're free to imagine any chain of causation you'd like but I doubt that it will be more plausable or direct than low intelligence causes poverty. Seems pretty clear to me.

[LadyWrestler]

"So, is evolution still a power on humankind or not?"

IMHO: Yes...in one direction or the other...for better or worse...still a power.

Have a great day! /images/graemlins/smile.gif