Human Evolution
Discussion
Have we, as a species, stopped evolving, specifically in the west.
Two of the main drivers of evolution:
1/ Producing more off spring than the environment can sustain.
2/ Only the most fit to the environment reproduce.
Surly, in the west, both of the above are no longer true. No longer do we expect any significant infant mortality rate and the only limit on producing off spring is the willingness to have them. Again, to most people the numerical limit on children tends to be choice.
I don’t want to talk about “poor” people having lots of kids as I don’t think that poor people are genetically stronger or weaker than the “rich”.
So what is happening to us genetically? I know that in genetic terms we have only been in this situation for a tiny period of time but if we continue what happens?
One thing that does concern me is that (after talking to a doctor who thought that it was crazy spending hundreds of thousands of pounds on young cancer patients when the fact that they had got cancer so young just meant that they were massively predisposed to get cancer and so even if initially cured would just go on to get repeated cancer at a far higher rate than the general population in the future) people who would have died of a disease that they are genetically predisposed toward now no longer do so and they go on to breed that gene into the general population. Are future generations going to be more affected by genetic problems?
My general feeling on our genetic future is that instead of removing the “weak” and promoting the “strong” we are in a situation where we are simply mixing.
Is there still a driver to remove “weak” genes and promote “strong” ? If so, what is it?
Two of the main drivers of evolution:
1/ Producing more off spring than the environment can sustain.
2/ Only the most fit to the environment reproduce.
Surly, in the west, both of the above are no longer true. No longer do we expect any significant infant mortality rate and the only limit on producing off spring is the willingness to have them. Again, to most people the numerical limit on children tends to be choice.
I don’t want to talk about “poor” people having lots of kids as I don’t think that poor people are genetically stronger or weaker than the “rich”.
So what is happening to us genetically? I know that in genetic terms we have only been in this situation for a tiny period of time but if we continue what happens?
One thing that does concern me is that (after talking to a doctor who thought that it was crazy spending hundreds of thousands of pounds on young cancer patients when the fact that they had got cancer so young just meant that they were massively predisposed to get cancer and so even if initially cured would just go on to get repeated cancer at a far higher rate than the general population in the future) people who would have died of a disease that they are genetically predisposed toward now no longer do so and they go on to breed that gene into the general population. Are future generations going to be more affected by genetic problems?
My general feeling on our genetic future is that instead of removing the “weak” and promoting the “strong” we are in a situation where we are simply mixing.
Is there still a driver to remove “weak” genes and promote “strong” ? If so, what is it?
I have often pondered on this too. In the 'natural' world, many conditions would kill their host before reproduction, or significantly reduce fertility such that offspring numbers and viability would be reduced. These condition would still exist but in a much lesser degree if intervention by the medics were not to happen allowing their sufferers to live longer and propagate their (faulty) genes. However, there is more than one kind of evolution I suspect, and genetic and physical changes which may be interfered with by science are accompanied by what I term 'software' evolution. A good example of this is rabbits tending to build surface 'nests' because myxomatosis is less likely to be propagated in open air breeding quarters than in the more normal underground warrens. I have searched for a supporting article on this in vain, but I heard it stated on a BBC nature programme some years ago. Likewise, birds will imitate local sounds on their particular territory and, perhaps, gain some advantage from doing so. These are software changes (behavioural) rather than physical changes such as weight or length of body. Is it possible that humans, too, have changed in their behaviour (unconsciously) to gain a head start over rivals?
jmorgan said:
Depends if we have left the nest or not. But life else where, if it exists, will not stop.
But does it evolve? We only have a sample of one planet to work with which does not give us enough data to speculate whether a continuous evolutionary mechanism is a common phenomena or a one off.plasticpig said:
Eric Mc said:
No.
Evolution never stops.
Your wrong. Evolution will stop when the sun transforms to a red giant and all life is wiped out from planet Earth. Evolution never stops.
Eric Mc said:
No.
Evolution never stops.
So, with humanity (in the west) being able choose at will to replicate, and with a more or less 100% chance of the replicant itself getting to the age where it can also choose if it wishes to replicate and how often to do so, where is the evolutionary element?Evolution never stops.
Also, from Wiki:
"Traditionally, the coelacanth was considered a “living fossil” due to its apparent lack of significant evolution over the past millions of years;[3] and the coelacanth was thought to have evolved into roughly its current form approximately 400 million years ago"
Given a form of life which has imperfect replication leading to heritable variation in phenotype and differential reproductive success subject to modification by phenotype, evolution is inevitable.
Humans will continue to evolve. We aren't anywhere near the elimination of the influence of heritable traits on reproductive success. We will never do so as long as, for example, people are free to choose their own mates and when and whether to have children. And even if you were able to remove all selection pressures, we would still be subject to genetic drift and mechanisms like the founder effect. If humanity does ever succeed in vacating this rock and colonising other worlds, the geographic isolation involved guarantees eventual speciation through those effects alone.
Humans will continue to evolve. We aren't anywhere near the elimination of the influence of heritable traits on reproductive success. We will never do so as long as, for example, people are free to choose their own mates and when and whether to have children. And even if you were able to remove all selection pressures, we would still be subject to genetic drift and mechanisms like the founder effect. If humanity does ever succeed in vacating this rock and colonising other worlds, the geographic isolation involved guarantees eventual speciation through those effects alone.
Liokault said:
Eric Mc said:
No.
Evolution never stops.
So, with humanity (in the west) being able choose at will to replicate, and with a more or less 100% chance of the replicant itself getting to the age where it can also choose if it wishes to replicate and how often to do so, where is the evolutionary element?Evolution never stops.
Also, from Wiki:
"Traditionally, the coelacanth was considered a “living fossil” due to its apparent lack of significant evolution over the past millions of years;[3] and the coelacanth was thought to have evolved into roughly its current form approximately 400 million years ago"
Evolution can slow down depending on all sorts of environmental and ecological issues. It CAN stop when a species or sub species becomes extinct. But as long as the species remains in existence, the potential for change will remain and will happen.
Assuming that our current "technological" status is somehow causing us to stop evolving is extremely naive. We may not retain this status at all.
Edited by Eric Mc on Monday 13th January 12:12
I see evolution varying depending on where in the world and what part of society you are in.
In poor/underdeveloped countries evolution continuies in its natural form - the weak, sick and slow-witted dying, the strong and smart surviving, and food supplies controlling population. That is evolution as it's usually understood, and keeps the species biologically fitter and better able to survive.
In highly educated 'Western' environments, intelligent high-achieving people are likely to produce similar children better able to thrive in a high-tech modern environment. The fact they can't kill a rabbit for food is not important.
In some societies it is seen proper to take pity on those less fortunate and give them money and houses. Fine at the outset, this removes the necessity to do anything or be good at anything and can have the unexpected result of a dependency culture. Freed of natural or normal restraints, conditions in this bubble are ideal for reproduction at the expense of others.
And so I think evolution continues but in differing and not always healthy directions. We may yet end up with a 'Time Machine' world of Eloi and Morlocks...
In poor/underdeveloped countries evolution continuies in its natural form - the weak, sick and slow-witted dying, the strong and smart surviving, and food supplies controlling population. That is evolution as it's usually understood, and keeps the species biologically fitter and better able to survive.
In highly educated 'Western' environments, intelligent high-achieving people are likely to produce similar children better able to thrive in a high-tech modern environment. The fact they can't kill a rabbit for food is not important.
In some societies it is seen proper to take pity on those less fortunate and give them money and houses. Fine at the outset, this removes the necessity to do anything or be good at anything and can have the unexpected result of a dependency culture. Freed of natural or normal restraints, conditions in this bubble are ideal for reproduction at the expense of others.
And so I think evolution continues but in differing and not always healthy directions. We may yet end up with a 'Time Machine' world of Eloi and Morlocks...
Eric Mc said:
Liokault said:
Eric Mc said:
No.
Evolution never stops.
So, with humanity (in the west) being able choose at will to replicate, and with a more or less 100% chance of the replicant itself getting to the age where it can also choose if it wishes to replicate and how often to do so, where is the evolutionary element?Evolution never stops.
Also, from Wiki:
"Traditionally, the coelacanth was considered a “living fossil” due to its apparent lack of significant evolution over the past millions of years;[3] and the coelacanth was thought to have evolved into roughly its current form approximately 400 million years ago"
Evolution can slow down depending on all sorts of environmental and ecological issues. It CAN stop when a species or sub species becomes extinct. But as long as the species remains in existence, the potential for change will remain and will happen.
Assuming that our current "technological" status is somehow causing us to stop evolving is extremely naive. We may not retain this status at all.
Edited by Eric Mc on Monday 13th January 12:12
As we seem to have side stepped some of the traditional evolutionary drivers, what is our vector?
plasticpig said:
Eric Mc said:
No.
Evolution never stops.
Your wrong. Evolution will stop when the sun transforms to a red giant and all life is wiped out from planet Earth. Evolution never stops.
Liokault said:
I'm not suggesting anything, I'm asking a question.
As we seem to have side stepped some of the traditional evolutionary drivers, what is our vector?
No we haven't.As we seem to have side stepped some of the traditional evolutionary drivers, what is our vector?
The time period covered by this "sidestepping" (as you call it) is tiny compared with the time periods required for evolutionary changes. Humans have not changed much, if at all, over 100,000 years, but have changed dramatically over 6 million years.
Come back in 6 million years and see how the species is doing.
Eric Mc said:
No we haven't..
Ok, we haven’t side stepped itEric Mc said:
The time period covered by this "sidestepping" (as you call it) is tiny compared with the time periods required for evolutionary changes..
Hold on, we have sidestepped it (as I do call it), please make your mind up.Also in the OP I stated "I know that in genetic terms we have only been in this situation for a tiny period of time".
Eric Mc said:
Come back in 6 million years and see how the species is doing.
Yeah, see, in the OP I asked people to conjecture what would happen over a longer period of time. You know, to give us desk slaves something to do over a long slow lunch.If you don't want to get involved with this conjecture, and would instead like to shut a thread down with a glib minimal reply, please go away.
You seem to misunderstand evolution. It is not about "strong" vs "weak", it is all about the organisms fitness for it's current environment. Humans are still evolving and will continue to do so in whatever way maximises our ability to reproduce. This may lead to us becoming weaker but more intelligent (as it has in the past) or may lead us in another direction such as weak but beautiful (a la birds of paradise) but this does not imply it has stopped.
Liokault said:
Eric Mc said:
No we haven't..
Ok, we haven’t side stepped itEric Mc said:
The time period covered by this "sidestepping" (as you call it) is tiny compared with the time periods required for evolutionary changes..
Hold on, we have sidestepped it (as I do call it), please make your mind up.Also in the OP I stated "I know that in genetic terms we have only been in this situation for a tiny period of time".
Eric Mc said:
Come back in 6 million years and see how the species is doing.
Yeah, see, in the OP I asked people to conjecture what would happen over a longer period of time. You know, to give us desk slaves something to do over a long slow lunch.If you don't want to get involved with this conjecture, and would instead like to shut a thread down with a glib minimal reply, please go away.
As I said, we haven't sidestepped anything. 100,000 years is far too short a period to observe any clear evolutionary changes in a sophisticated life form such as a higher mammal (which we are).
Over a period in the order of millions of years, it is likely that we WOULD see such changes.
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