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Future Human Evolution

  1. Apr 29, 2010 #1
    Do you think that the human species will survive long enough to produce a new subspecies or a separate species? Personally, I think we are doomed to kill ourselves off prior to an new development. However, our species comes from a long line of individuals that have adapted and survived many extinction events. Thoughts?
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  3. Apr 29, 2010 #2

    If we haven't drastically changed our species in the past 4000+ years, I doubt we ever will. Why would we have a need to?

    We'll die, but there isn't a current MAJOR threat. (note, current) Not one that will cause us to start evolving.
  4. May 6, 2010 #3
    well seeing as how our perception of our environment controls our genes, you can never know, but i can. get it?
    Last edited: May 6, 2010
  5. May 6, 2010 #4


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    We have made lots of minor changes.

    About half of us can metabolize lactose as adults as well as alcohol.
    A minority have blond hair and pale skin to make vitamin D
    Most of those have genes to protect against plague.
  6. May 8, 2010 #5
    You need a natural selection pressure. If you have a high child mortality rate due to episodes of malnourishment or diseases, then being lactose intolerant will be a hugely significant factor.

    But today, the number of surviving children we have is a almost 100% a matter of personal choice. So, I think one should consider if there are genetic factors that influences this choice to have (many) children. E.g., I think that higher educated people tend to have less children. If there are genes that influence this choice, then that could lead to Homo Sapiens dumbing down.
  7. May 8, 2010 #6


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    And now we are beginning to modify our own genes.
  8. May 8, 2010 #7
    We don't really NEED to modify our genes, though. We're just kinda doing it.
  9. May 9, 2010 #8
    In fact genetically modified organisms (GMOs) represent a new phase of evolution, based not on natural selection, but on intelligent design (ID), the designers being us. That's not to say we, as a species, are intelligent enough to do it right and natural selection will still play a role. However, there's no reason in principle why we couldn't, in the future, with a combination of bionics and ID create new life forms with extraordinary capabilities. Obviously, that capability applies to modifying ourselves as well as other species.

    What we have with GMOs is life designing life, with the possible result of a very rapid acceleration in the 'evolution' of many new life forms including ourselves. ID can be aided by enormous increases in information processing power leading to effective artificial intelligence (AI). The combination of AI and ID carries with it enormous potential and not a small amount of danger.

    Right now, some kind of bacterial/algae GMOs designed to metabolize crude oil and break it down to harmless byproducts would be very useful in the Gulf of Mexico.
    Last edited: May 9, 2010
  10. May 9, 2010 #9


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    Yes, this is what I meant. I also believe that some things that we view today as biologically wrong to do, will be viewed by future generations as a God-given right. It won't happen as one sudden change but rather as a little here, a little there.

    I don't remember where I read it but, I thought that it had been done already.
  11. May 9, 2010 #10


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    I agree that directed evolution is probably the next phase of human evolution. If in fact we can improve the species through genetic engineering (and I think that there is little doubt that we can - or at least will be able to in at most a few decades), then it doesn't take everyone to agree that it should be done. It just takes one small group of people to decide to do it, and it could be done initially in secret. Is it reasonable to assume that nobody will decide to use genetic engineering, ever? I think no. Some group will decide to use it, will create a genetically superior breed of humans, and these genetically superior humans will replace the current ones. Our species hasn't historically shown a lot of compassion for our ancestors as our evolution has progressed. Just ask Homo Erectus or the Neanderthals.
  12. May 9, 2010 #11
    The next logical change might result from living longer. Modern medicine has extended lifecycles, but our bodies become very frail. Perhaps our bodies will adapt?
  13. May 9, 2010 #12
    Unless it helps pass strong genes on to new generations, I don't think it will be evolved. Think of it as the genes which are going through evolution, and our bodies are merely the vessel for these genes to reproduce themselves.
    I think we can certainly expect change in the human race, but in what direction is unsure. We no longer live in a survival of the fittest scenario, and poor genes are passed on more commonly.
  14. May 9, 2010 #13
    Yes, I guess you'll end up with fitness levels declining to the point where it does start to influence survival. Any fitter than that and there is no selction pressure so, random mutations will lead to fitness declining. Less fit than this and then, of course, you do have a selection pressure.

    But I think that animals have evolved a mechanism against degeneration in the absense of natural selection pressure: Sexual selection. In case of humans, this mechanism doesn't work well either (e.g. due to cosmetic surgery), so we may be doomed.
  15. May 9, 2010 #14


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    1] 4000 years is the blink of an eye in evolutionary terms. That being said, we do see small changes over just a few generations.
    2] Need to has nothing to do with it. Evolution happens regardless. It sure doesn't require any major threat.
    3] We are evolving all the time.
  16. May 9, 2010 #15
    That's why I said drastically.

    I suppose there are always small changes.
    Last edited: May 9, 2010
  17. May 9, 2010 #16


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    It's all about the small changes.

    Drastic changes are simply accumulated small changes over a relatively short time (or more like between two times where we don't have many samples between them).

    I have a friend who was born with six fingers on each hand. Give that a few thousand years under the right circumstances and you might have a big change in the population.
  18. May 10, 2010 #17
    You also need genetic isolation. Or you need some kind of substantial rare change, like a change in the number of chromosomes, that will divide the population "in place" by messing with inter-group mating. Natural selection can introduce all kinds of changes, but, unless you have multiple groups in isolation from each other, these changes just spread throughout the entire population. So you never end up with a genuinely new species.

    And you need to maintain genetic isolation for a loooong time. It was just announced that there's evidence of interbreeding between neanderthals and cro-magnons. And those were isolated for something like 300,000 years. On the other hand, humans and chimpanzees separated around 5 million years ago, and so far all attempts to hybridize them have been unsuccessful. So that gives you a timescale of species formation.
  19. May 15, 2010 #18
    One of the major issues I think that many forget in human evolution is the exponential combination of natural and manmade environmental influences on our cells at every level. Radon gas is a continual bombardment issue as it is the 2nd leading cause of lung cancer in the US alone plus the many other potential side effects. Combine that with the bombardment of radio waves today in our homes and cars, I almost feel like I live in a micro wave oven with new phones, computers, games, ovens and even in our vehicles. Combine this with vaccines, medications, climate change, not even to getting into selective engineered reproduction with intelligence being highly sought after, you begin to get the idea of a direction that evolution for humans is heading. I dont know if this is good or bad but these issues cannot be ignored. What say you all?
  20. May 16, 2010 #19


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    What direction?
  21. May 16, 2010 #20
    I think the direction and end result will of course be a society of good looking physics nerds with exponential psychokinetic ability with xray vision, It's called the cybersysop law of evolution, LOL!!
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