Interesting Stuff Thread

Flamed Diving

sink wrote: »

Bingo, answered your own question, but there is more to it.

What is interesting about our species is that we no longer rely upon our physical bodies to do work. We build specialised tools to suit all situations so we do not face the same pressures that all other lifeforms face and these are the pressures that drive evolution. So in effect we have stopped evolving to a certain extent.

How can we 'stop evolving'?

Flamed Diving

Flamed Diving wrote: »

How can we 'stop evolving'?

Because we, humans, don't necessarily have as strong an external force as natural selection acting upon us anymore. Technology and science have basically, to a high level anyway, freed us from natural selection.

Flamed Diving

-JammyDodger- wrote: »

Because we, humans, don't necessarily have as strong an external force as natural selection acting upon us anymore. Technology and science have basically, to a high level anyway, freed us from natural selection.

I get ya, but I think it is a bit strong to state that human evolution has stopped. There will always be selective forces. Sexual selection doesn't disappear, for example.

Flamed Diving

Flamed Diving wrote: »

I get ya, but I think it is a bit strong to state that human evolution has stopped. There will always be selective forces. Sexual selection doesn't disappear, for example.

Yah, I'd agree. It just doesn't affect us as much as it used to. We can, in some ways, control what external forces affect us, thus, controlling our own evolution to some extent.

Anyway, this is getting a bit off the topic of this thread - don't want to get in trouble with Dades:p

kiffer

-JammyDodger- wrote: »

Because we, humans, don't necessarily have as strong an external force as natural selection acting upon us anymore. Technology and science have basically, to a high level anyway, freed us from natural selection.

I disagree...
1, We're only looking at short term human scale situations...
2, The removal of selection pressure allows all sorts of mutations which would be bad enough to prevent an individual from reproducing to be come established.
Once selective pressures return some of these might be useful...

So when the Zombie Apocalypse comes... those of terachromatic women will be able to spot the zombies faster than normal people and have an advantage.

I guess the question is ... what selection pressures, if any, will we encounter in the future.

sink

Flamed Diving wrote: »

I get ya, but I think it is a bit strong to state that human evolution has stopped. There will always be selective forces. Sexual selection doesn't disappear, for example.

That's why I qualified it by adding 'to a certain extent'. In addition to sexual selection viruses and bacteria are still forcing our immune system to evolve. However both of these are being limited by cosmetics and medicine. So while we haven't broken free from evolution completely we have limited it's effects to a massive extent.

I think that we will begin to evolve ourselves at some stage in the future, through genetic engineering. This will happen out of necessity for we will need to replace the process of natural selection which kept our species genes fit for survival with an artificial process. If we don't the human race will gradually get sicker and less fit as more and more people are born with degenerative disease who through the help of medicine live to pass on their less fit genes compounding the problem.

Dave!

Here's part 1 of a rather interesting David Attenborough documentary on evolution
http://www.youtube.com/watch?v=8MW1IZB9ThA

Follow the links to parts 2-5!

Also, apparantly humans and chimps are more similar than one type of yeast is to another
http://www.sciencedaily.com/releases/2009/02/090213114325.htm

ChocolateSauce

As we are no longer struggling to survive (some of us anyway), evolution will invariably slow down to a near halt in humans, except that I think in the future, possibly starting this generation, we will grab the reigns and start unnaturally selecting ourselves.

As was discussed in a thread last week, this leads to many moral questions, but by and large I see no problem in humans making themselves immune to disease through genetic manipulation etc. The important thing to avoid at all costs a situation where there are genetic haves and have-nots.

Flamed Diving

ChocolateSauce wrote: »

As we are no longer struggling to survive (some of us anyway), evolution will invariably slow down to a near halt in humans, except that I think in the future, possibly starting this generation, we will grab the reigns and start unnaturally selecting ourselves.

As was discussed in a thread last week, this leads to many moral questions, but by and large I see no problem in humans making themselves immune to disease through genetic manipulation etc. The important thing to avoid at all costs a situation where there are genetic haves and have-nots.

I don't get this, I have a simple equation in my head:

Mutation + Natural Selection = Evolution

I don't see how either of these can simply stop having an effect on humans. Is there any literature to back your statements up?

Scofflaw

ChocolateSauce wrote: »

As we are no longer struggling to survive (some of us anyway), evolution will invariably slow down to a near halt in humans, except that I think in the future, possibly starting this generation, we will grab the reigns and start unnaturally selecting ourselves.

As was discussed in a thread last week, this leads to many moral questions, but by and large I see no problem in humans making themselves immune to disease through genetic manipulation etc. The important thing to avoid at all costs a situation where there are genetic haves and have-nots.

Hmm. Evolution isn't a question of who survives, but of who breeds. There is usually extremely rapid evolution in a population that has moved into a relatively unexploited environment - and in humanity's case, that's where we are. When the glaciers retreated, we moved into a whole range of environments, with which we have yet to come into equilibrium.

That's borne out by studies showing that human evolution is currently very fast - starting about 40,000 years ago, and picking up even more with the development of agriculture. See here, for example.

It's easy to think that because most of us (in the rich world) aren't really subject to lethal selection pressures, there are therefore no selection pressures - but in fact there are, amongst other things, large differences between family sizes in different human communities.

cordially,
Scofflaw

MrPudding

Flamed Diving wrote: »

I don't get this, I have a simple equation in my head:

Mutation + Natural Selection = Evolution

I don't see how either of these can simply stop having an effect on humans. Is there any literature to back your statements up?

Particularly mutation. Correct me if I am wrong, but selection pressure, or lack thereof, would have no effect on mutation? Mutations will occur whether or not the mutations are being selected for or against.

Also, there may not be much in the way of life or death selection happening in the human race but I think there is still selection.

MrP

Flamed Diving

MrPudding wrote: »

Particularly mutation. Correct me if I am wrong, but selection pressure, or lack thereof, would have no effect on mutation? Mutations will occur whether or not the mutations are being selected for or against.

Also, there may not be much in the way of life or death selection happening in the human race but I think there is still selection.

MrP

Well mutation is simply a copying error in DNA. So as long as DNA performs these errors, there will always be mutation. People seem to think that because humans have created civilisation, this means that NS is factored out. Why? Because we don't have bears and lions chasing us anymore? I have huge doubts as to this kind of thinking. NS is driven by the environment, the environment is anything that exist outside of 'the self', this will never cease to exist. Maybe people can enlighten me on this matter. But I think it is nonsense.

Dave!

Flamed Diving wrote: »

Well mutation is simply a copying error in DNA. So as long as DNA performs these errors, there will always be mutation. People seem to think that because humans have created civilisation, this means that NS is factored out. Why? Because we don't have bears and lions chasing us anymore? I have huge doubts as to this kind of thinking. NS is driven by the environment, the environment is anything that exist outside of 'the self', this will never cease to exist. Maybe people can enlighten me on this matter. But I think it is nonsense.

I agree... I'm not terribly educated on the subject (just interested in it), but to me the idea that we're "finished evolving" seems extremely humano-centric.

MrPudding

Dave! wrote: »

I agree... I'm not terribly educated on the subject (just interested in it), but to me the idea that we're "finished evolving" seems extremely humano-centric.

My thoughts exactly, I am only educated to a "read a few Dawkins books and all of Atomic Horror's posts" but it just seems wrong.

For a start, sexual selection is alive and kicking.

MrP

robindch

MrPudding wrote: »

sexual selection is alive and kicking.

Indeedy.

I asked my niece a year or two back why she liked that unbelievably crappy orange foundation -- the stuff that's lobbed on with a table-tennis bat in the bedrooms of the nation's teens. She said that she didn't like it herself (er, cough, cough), but that "all the girls who used it had boyfriends".

'nuf said.

MrPudding

Quite scary. Does that mean that women with a slightly orangy natural hue to their skin are more likely to reproduce? I have to say, when I think about how humans will look in a few thousand years bright orange faces did not feature...

MrP

robindch

MrPudding wrote: »

Does that mean that women with a slightly orangy natural hue to their skin are more likely to reproduce?

A horrible thought, but as it stands, I think it's more likely that a tendency to wear dangerously crappy makeup is going to spread throughout the population.

Perhaps it already has...

Galvasean

While I wouldn't go so far as to say evolution has stopped in humans, it certainly isn't being directed (if that is the correct phrase, bear with me).
Think about it, as far as sexual selection is concerned there is no major stand out factor for being selected. Pretty people (heck if you are not naturally pretty you can get plastic surgery) can mate with ugly people. Olympic champions can breed with scientists.
What I'm trying to get at here is that since pretty much every trait is being reabsorbed into the gene pool, nothing is being weeded out.
Personally I think it would take a long and planet wide catastrophe before humans would start to evolve in a particular direction.

Mickeroo

Read H.G. Wells' The Time Machine, i think it was well before its time in saying how all our technology etc could effect our evolution.

sink

Galvasean wrote: »

While I wouldn't go so far as to say evolution has stopped in humans, it certainly isn't being directed (if that is the correct phrase, bear with me).
Think about it, as far as sexual selection is concerned there is no major stand out factor for being selected. Pretty people (heck if you are not naturally pretty you can get plastic surgery) can mate with ugly people. Olympic champions can breed with scientists.
What I'm trying to get at here is that since pretty much every trait is being reabsorbed into the gene pool, nothing is being weeded out.
Personally I think it would take a long and planet wide catastrophe before humans would start to evolve in a particular direction.

Natural selection requires that a selection is made. Demographics in the affluent west suggest that this isn't happening. Out of all the babies born a very large percentage of them make it to adulthood, and there are barely enough births to maintain current population levels. Conditions that would have been selected against in the past get by, such as diabetes and poor eyesight. Meanwhile conditions that would have been selected for in the past are not out breeding those without, e.g. intelligence, good looks and general health. So while some of the most intelligent and/or beautiful and healthy people on the planet are not procreating and some less intelligent/good looking/healthy people are having multiple children. Where does the genetic selection take place? Evolution theory holds that more mutations are taking place due to our larger population size (although this is in doubt see Steve Jones). But if no selection is taking place all these genetic mutations will persist, whether they are good or bad, It could be that rather than genetic selection, psychosocial factors play the largest role in selection. But what does this mean for the future of our species?

Of course if you factor in the developing world this idea falls flat on it's face. But it is an interesting idea.

Galvasean

National geographic has announced it's top 7 "missing links" that have been discovered since the publication of The Origin of Species.

You can check them out here.

AtomicHorror

MrPudding wrote: »

My thoughts exactly, I am only educated to a "read a few Dawkins books and all of Atomic Horror's posts" but it just seems wrong.

For a start, sexual selection is alive and kicking.

MrP

As is genetic drift. As has been correctly pointed out, whether natural selection is active on a given trait or not, mutation continues. The chances that NS is not working on any of our traits is negligible. It's not possible to stop evolving without stopping breeding. We are absolutely continuing to evolve unless our understanding of evolution is completely wrong.

AtomicHorror

Galvasean wrote: »

While I wouldn't go so far as to say evolution has stopped in humans, it certainly isn't being directed (if that is the correct phrase, bear with me).
Think about it, as far as sexual selection is concerned there is no major stand out factor for being selected. Pretty people (heck if you are not naturally pretty you can get plastic surgery) can mate with ugly people. Olympic champions can breed with scientists.
What I'm trying to get at here is that since pretty much every trait is being reabsorbed into the gene pool, nothing is being weeded out.
Personally I think it would take a long and planet wide catastrophe before humans would start to evolve in a particular direction.

How do you quantify evolutionary "direction"? How can a trait be "reabsorbed" into the gene pool? If a trait exists, it's in the gene pool.

Ugly people can get plastic surgery, if they are wealthy enough. In which case their wealth may already be an adequate incentive for a good mate. Olympic champions and scientist both have strongly favourable traits, but with differing focuses.

It is very difficult to look at any species, even a thriving species such as humans and pick out how natural selection is currently working, what the pressures are. But it would be a mistake to assume that it is not. It isn't working in the same way that it works on some animal species, but as long as people are dying childless at whatever age, it is working. The million-year retrospective view would doubtlessly be very informative.

AtomicHorror

sink wrote: »

Natural selection requires that a selection is made.

Nonsense. It requires that you die without having a kid. It's not an active process, that's sexual selection.

sink wrote: »

Demographics in the affluent west suggest that this isn't happening.

Medical technology has shifted selective pressures away from many traits but it certainly hasn't eliminated natural selection's influence on us. The psychosocial arises ultimately from the biological anyway, so even if the influence of genetics is rather broad and fuzzy there, it will still amount to some level of selection on biology.

Goduznt Xzst

Have we evolved to the point though that sexual selection is starting to have a detrimental affect on our evolutionary progress?

I mean I remember seeing statistics that indicated that the higher a persons IQ or the greater their ability to achieve success the lower the number of children they would have. Whereas the inverse tended to be true.

This idea was made light of in the movie "Idiocracy". I'm just curious as to how much bearing members here would put in this idea?

AtomicHorror

Goduznt Xzst wrote: »

Have we evolved to the point though that sexual selection is starting to have a detrimental affect on our evolutionary progress?

From whose perspective? Things survive to breed or they don't, that's the only judgement present in the system. We may find certain traits undesirable, but our evolutionary progress has nothing to do with the where we think the species ought to be going.

Goduznt Xzst wrote: »

I mean I remember seeing statistics that indicated that the higher a persons IQ or the greater their ability to achieve success the lower the number of children they would have. Whereas the inverse tended to be true.

This might well be correct, but again I think you're coming from an anthropocentric point of view here. You see the uniquely human trait of intelligence as something that evolution "should" be moving us towards. But it doesn't really work like that.

Goduznt Xzst

AtomicHorror wrote: »

From whose perspective? Things survive to breed or they don't, that's the only judgement present in the system. We may find certain traits undesirable, but our evolutionary progress has nothing to do with the where we think the species ought to be going.

This might well be correct, but again I think you're coming from an anthropocentric point of view here. You see the uniquely human trait of intelligence as something that evolution "should" be moving us towards. But it doesn't really work like that.

I understand that evolution doesn't have a purpose and has no way of considering if a trait is a positive one or negative one and that the only determining factor is which one survives. But I wouldn't go as far as to say that its anthropocentric. Rather our brains have proven to be a beneficial evolutionary step for our species thus far.

Do you imagine that we have reached a peak where the greater our intelligence gets the less likely we will be to pass on as much of our genes to the next generation as someone with a lower intelligence.

Simon.d

AtomicHorror wrote: »

Medical technology has shifted selective pressures away from many traits but it certainly hasn't eliminated natural selection's influence on us. The psychosocial arises ultimately from the biological anyway, so even if the influence of genetics is rather broad and fuzzy there, it will still amount to some level of selection on biology.

Was looking into this thread from time to time, and was meaning to say more or less the above.. It's completely naive to think we're beyond natural selection, or that we'll ever be.. Just look at the society we live in and you'll see major imbalances with regard to who's having the most children, i.e. those who don't have careers (or even jobs) to worry about are at it like rabbits.. While those with careers significantly impede their own genetic proliferation by indulging in ideas like family planning..

• Technologies like In Vitro fertilization will have the net-effect of reducing our populations over-all fertility..
• Laser eye surgery/Contact lenses with make those with genetically poor eye sight more successful with the opposite sex, thereby reducing our populations over all vision quality..
• Those prone to obesity will become less attractive to the opposite sex, thereby reducing our populations ability to withstand food shortages in the future (Fat storage being quite important at such times)
• Basically all medical intervention will have the net effect of making all genetically derived diseases more common.
  • Cancers will become more common
  • Heart problems will become more common
  • Could go on all day...

Essentially we'll continue to form a more and more dependent relationship with technology, meaning one day human survival may be impossible without it..

Fanny Cradock

Simon.d wrote: »

Essentially we'll continue to form a more and more dependent relationship with technology, meaning one day human survival may be impossible without it..

An interesting thought. One would imagine that we - or a proportion of the population - are already at such a stage. For instance, I wonder what chaos would ensue if a massive solar flare was to obliterate much of our electronics. Probably best discussed in another forum.

robindch

Fanny Cradock wrote: »

I wonder what chaos would ensue if a massive solar flare was to obliterate much of our electronics.

Well, there'd be thousands of boardsies out on the street instead of fulminating in the safety of their own padded bedrooms.

Chaos seems inevitable.