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What are we evolving into?

  1. Sep 2, 2006 #1
    Lets say that human race never gets destroyed, we keep evolving, would we one day be free of all deseases because our immune sys. be really strong? Would we be really smart?(why) I always see that as we evolve, people imagine we get smarter. What would cause us to get smarter? Maybe because we push our brains more every generation but I dont think genetics have anything to do with it.
     
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  3. Sep 2, 2006 #2

    selfAdjoint

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    Well right at the moment the adaptive gradient seems to be set against smarts. Smart women who have the freedom to do so elect to have fewer kids which biases the population growth toward those who are either not smart or not free.

    In the future there will be a period, at least of energy shortages, fresh water shortages, and rampant diseases, spread by modern global communications. AND ability of small terrorist groups to generate kiloton explosions. Those who survive this challenge best will differentially dominate the population of the future. It seems to me here and now that it will be those who best can live in an organized polity; no-one is going to be able to do this on their own, goodbye Rambo. Whether smart people can find a niche, as the Ashkenazi Jews did during the black death and the thirty years war, we don't know.
     
  4. Sep 2, 2006 #3
    As we are evolving, I have seen, heard, and read, that we become smaller and smaller physically, and get smarter. Well, first of all, that doesn't make sense to me. What is causing us to be that way? Second, if we aren't getting smaller? What exactly are we evolving into?

    I know you said that right now, we are getting more duffer in a way, but if it was just 1 familiy and if we just focus on 1 generation, in what way would we be evolving? I think I know that our immune sys. is getting stronger but so are the viruses.
     
  5. Sep 2, 2006 #4

    selfAdjoint

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    That small big-headed idea was an old one from the 1940s and 1950s, based on very shallow thinking. It's important to realize that evolution doesn't have a goal, it just a series of reponses to various challenges and it goeth where it listeth, like St. Paul's wind.

    It wouldn't be clear. You could look at the mother's alleles (gene types) and the father's, and see how they were expressed in the children, but even this would be oversimplified in the modern view becoause of things like epistatsis (proteins influencing genes) and recombination (jumping genes). The more people find out about genes the more complex the picture and the dynamics get.

    Evolution is like the minute hand of a clock; you can't see it moving but over an hour it goes clear around the clock.
     
  6. Sep 3, 2006 #5

    jim mcnamara

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    Natural Selection doesn't have predefined goals or directions. It isn't a vector - something with magnitude and direction.

    It is simply random environmental or social (as SA suggests) factors that create (or do not create) differential reproduction in populations.
    Populations can:
    stay more or less at "starting values" for long periods,
    drift randomly,
    go extinct,
    (fill in the blank with whatever you like).

    SA above kinda took the (fill in the blank) option to make a point.
    For humans, I personally favor the 'go extinct' option. In terms of probablilty based on observations of past species, at least, the 'go extinct' option is by far and away the most the most likely. Most species go extinct.

    Therefore, humans will evolve (or not), eventually reach a dead-end, and go extinct. Period. Several other species in the Homo genus have already preceded us into extinction.


    That isn't very much fun, is it? -- so go ahead and speculate.
     
  7. Sep 3, 2006 #6

    DaveC426913

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    As we have concluded, evolution does not have a direction or predictable outcome.

    In the same way, a 'dead-end' is a meaningless concept. There is no such thing as a dead-end, except inasmuch as a species cannot continue to survive and breed (because of natural or competitive barriers).

    Why would humans cease to be able to breed? Just because their evolution is going nowehere prediictable does not mean we won't continue to breed. Unless we were blown back an ice age civilisation and lost our smarts and technology...
     
  8. Sep 3, 2006 #7
    I read in a book that evolution is actually cycle. Is that another gossip?
     
  9. Sep 3, 2006 #8

    DaveC426913

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    Can you be more specific?

    If I were to interpolate the likely meaning of that, I would strongly lean toward nonsense.
     
  10. Sep 4, 2006 #9

    saltydog

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    We're so anthropocentric aren't we: purposes in life, goals, direction, and meaning. That's all good I think from a Darwinist perspective. Hey, whatever works in the interest of survival and reproductive success. Religion works too. Stripped however of it's humane trappings lies a dark, indifferent reality: chance caught in the breeze. But that's a harsh finality difficult to stomach for fragile creatures such as we, de-selective to do so I would think in fact. So we candy-coat it with faith, with purpose, and sanctity of life as strategies for survival.
     
    Last edited: Sep 4, 2006
  11. Sep 5, 2006 #10

    DaveC426913

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    Point of order.

    This thread has nothing to do with "anthropocentrism", "purposes", "meaning", "religion" or "candy-coating".

    The question posed is not a philosophical or theist question, nor is it even a humanistic question. It is simply about the 'direction' of evolution. Refreshingly so in fact.

    Please don't hijack it with what appears to be a kneejerk 'purpose in life' response.
     
  12. Sep 7, 2006 #11

    saltydog

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    I yield to you. Sorry guys for poisioning your thread. I do very much believe in staying focused on the topic of discussion and failed here. Will try to do a better job in the future.
     
  13. Sep 7, 2006 #12
    I think that medicine had created an model of how the human being should be like. Aberrations to what it is consider "normal" or "by the book", like a literally third eye, are removed by surgery and fixed. Our evolution is then slowed or stopped because these mutations are not given a chance.
     
  14. Sep 7, 2006 #13

    Another God

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    [C It is simply about the 'direction' of evolution. [/QUOTE]
    However it must be remembered that Evolution has no direction. The Evolutionary process is an entirely reactionary process. It may be interesting to propose potential outcomes, but it is no more than fun speculation about what the future holds. In order to do so you have to guess at whether a virus will strike or not, whether WW3 breaks out, whether we will invent a renewable energy source, whether we will expand into space... etc etc etc... Once you have guessed at the future environment, then u can try to guess how our biology might react over the course of many generations.
    Surgically altering a mutation does not affect the genetic profile of that individual and hence does not affect the inheritence of that same mutation.

    Most disfigurations which are operated on are caused by developmental issues though, not genetic ones.
     
  15. Sep 12, 2006 #14
    I actually think humans are evolving to be more susceptible to diseases of most kinds for the following reason:

    Medical improvements allow us to treat those with diseases that should be fatal into diseases that are not fatal. For example diabetes type I , we have provided treatments to this disease and allow those with the disease to have children and pass on the "defective" genes. This is true for other genetic abnormalities that decrease the chance of survival without the use of medical support.




    However I must say that I agree with the ideals of doing all we can to help everyone.
     
  16. Sep 12, 2006 #15

    Another God

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    Just because we are more able to survive a negative does not mean we are directed towards that.

    I mean, being able to survive more diseases doesnt create a selective pressure that makes us more susceptible to diseases. What it does do it create more scope for variability. Variability is very important for when a selective pressure is applied because there are more options and more chance of one or a million humans being adapted...
     
  17. Sep 13, 2006 #16
    I agree with you when you say there is more variability when we use medical applications to aid people with diseases that cannot be supported without them. Who knows what selection criteria may be called upon by our environment in the future.

    However, understand that 'natural' selection did not choose those with these diseases to survive, they are only 'artificially' surviving due to our medical advances.

    Also it is not always true that being able to survive more diseases doesnt create a selective pressure that makes us more susceptible to diseases. Because I would argue that certain diseases do make you susceptible to other diseases.
     
  18. Sep 16, 2006 #17
    I have a question about human evolution and so instead or making a new thread I'll ask it here.

    Recently, I was watching a news story on how flip flops are causing stress fractrues in insteps of feet because of lack of support. But why is this happening now? Prehistoric humans ran with no shoes so are we getting weaker or are the people with weak bones just surviving nowadays?
     
  19. Sep 16, 2006 #18

    selfAdjoint

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    The case of walking or running in flip-flops is quite different from the case of walking or running barefoot. Also notice that the paved surface we use much of the time did not exist in prehistoric times.
     
  20. Sep 18, 2006 #19
    One more thing concerning the difference between 'prehistoric' or 'pre-footware' man and today's man (post-footware.) Hard surfaces can be the bane of our bones since these surfaces don't absorb much of the impact like dirt or grassy areas did for pre-footware man.

    The notion of land being covered by concrete and asphalt and small patches of dirt such as those found in back yards is an amazing one. Think about that next your walking around in the city. Everything is covered by 'artificial' man-made materials.
     
  21. Sep 18, 2006 #20

    radou

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    We were devolving since the point we started to evolve. That's the human paradox. :biggrin:
     
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